AtriCure, Inc. - Annual Report: 2014 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2014

Commission File Number 000-51470

AtriCure, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number including area code: (513) 755-4100

Securities Registered Pursuant to Section 12(b) of the Act:

Securities Registered Pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ¨    No  x

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act.    Yes  ¨    No  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

The aggregate market value of the voting Common Stock held by non-affiliates of the registrant, based upon the closing sale price of the Common Stock on June 30, 2014, as reported on the NASDAQ Global Market, was $478.3 million.

As of February 20, 2015 there were 27,590,646 shares of Common Stock, $.001 par value per share, outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Items 10, 11, 12, 13 and 14 of Part III of this Form 10-K incorporate information by reference from the registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission within 120 days after the end of the fiscal year covered by this Form 10-K.

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TABLE OF CONTENTS

Table of Contents

PART I

This Form 10-K, including the sections titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Risk Factors,” contains forward-looking statements regarding our future performance. All forward-looking information is inherently uncertain and actual results may differ materially from assumptions, estimates or expectations reflected or contained in the forward-looking statements as a result of various factors, including those set forth under “Risk Factors” and elsewhere in this Form 10-K. Forward-looking statements convey our current expectations or forecasts of future events. All statements contained in this Form 10-K other than statements of historical fact are forward-looking statements. Forward-looking statements include statements regarding our future financial position, business strategy, budgets, projected costs, plans and objectives of management for future operations. The words “may,” “continue,” “estimate,” “intend,” “plan,” “will,” “believe,” “project,” “expect,” “anticipate” and similar expressions may identify forward-looking statements, but the absence of these words does not necessarily mean that a statement is not forward-looking. With respect to the forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. These forward-looking statements speak only as of the date of this Form 10-K. Unless required by law, we undertake no obligation to publicly update or revise any forward-looking statements to reflect new information or future events or otherwise.

(Dollar amounts in this Part I are in thousands.)

Overview

We are a medical device company providing innovative atrial fibrillation (Afib) solutions designed to produce superior outcomes that reduce the economic and social burden of atrial fibrillation. We have two primary product lines for the ablation of cardiac tissue. Our Isolator Synergy^® Ablation System is the first and only surgical device approved by the United States Food and Drug Administration (FDA) for the treatment of Afib. Our cryoICE^™ cryosurgery product line offers a variety of both single use and reusable cryoablation devices. Our AtriClip^® Left Atrial Appendage Exclusion System is the most widely sold device worldwide specifically designed to occlude the heart’s left atrial appendage (LAA). We believe cardiothoracic surgeons are adopting our ablation and LAA management (LAAM) devices to cure Afib and reduce Afib-related complications such as stroke.

Cardiothoracic surgeons have adopted our radiofrequency (RF) ablation and cryoablation systems to treat Afib in an estimated 170,000 patients since 2004, and we believe that we are currently the market leader in the surgical treatment of Afib. Our products are utilized by cardiothoracic surgeons during both open-heart and minimally invasive procedures, either on a concomitant or sole-therapy basis. During a concomitant procedure, the surgeon ablates cardiac tissue and/or excludes the left atrial appendage, secondary, or concomitant, to a primary cardiac procedure such as a valve replacement or coronary artery bypass graft (CABG). Our Isolator Synergy System, which includes our Isolator Synergy clamps, generator and switchbox, is approved by FDA for the treatment of persistent and long-standing persistent Afib in patients who are undergoing open concomitant coronary artery bypass grafting and/or valve replacement or repair. To date, none of our other products have been approved or cleared by FDA specifically for the treatment of Afib. Our 510k-cleared RF ablation products are indicated for the ablation of cardiac tissue. Our 510k-cleared cryosurgery products are indicated for the treatment of cardiac arrhythmias. Our AtriClip products are 510k-cleared with an indication for occlusion of the LAA, under direct visualization, in conjunction with other open cardiac surgical procedures. We anticipate that substantially all of our revenue for the foreseeable future will relate to products we currently sell, or are in the process of developing, which surgeons use to treat Afib, exclude the left atrial appendage, or repair or replace mitral and aortic valves.

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Afib affects approximately 1% of the population in the United States. It is the most common cardiac arrhythmia, or irregular heartbeat, encountered in clinical practice and accounts for more doctor visits and hospital days than any other cardiac arrhythmia. Afib is a condition wherein abnormal electrical impulses cause the atria, or upper chambers of the heart, to fibrillate, or quiver, at rapid rates of 400 to 600 beats per minute. As a result of this quivering, blood in the atria may become static, creating an increased risk that a blood clot will form and cause a stroke or other serious complications. If Afib persists, patients often progress from experiencing Afib intermittently to having Afib continuously, a condition that is more difficult to treat. Symptoms of Afib may include heart palpitations, dizziness, fatigue and shortness of breath, and these symptoms may be debilitating and life threatening in some cases. Although there is often no specific cause of Afib, the condition is often associated with high blood pressure and other forms of heart disease. In most cases, Afib is associated with cardiovascular disease, in particular hypertension, congestive heart failure, left ventricular dysfunction, coronary artery disease and valvular disease.

In the United States we primarily sell our products to medical centers through our direct sales force. AtriCure Europe B.V., our wholly-owned subsidiary incorporated and based in the Netherlands, markets and sells our products throughout Europe and the Middle East primarily through distributors, while in certain markets, such as Germany, France and the Benelux region, sales are made directly to medical centers. Additionally, we sell our products to other international distributors, primarily in Asia, South America and Canada. Our business is primarily transacted in U.S. dollars with the exception of transactions with our European subsidiary which are substantially transacted in Euros or British Pounds.

We were incorporated in the State of Delaware as AtriCure, Inc. on October 31, 2000 in connection with a spin-off transaction from Enable Medical Corporation (Enable) in which shares of our common stock were distributed to Enable shareholders. The spin-off was intended to allow us to focus on the development of products designed to treat Afib and to raise capital for that purpose, while Enable continued its broader research and manufacturing activities. On August 5, 2005, we completed an initial public offering of our common stock. On August 10, 2005, we acquired Enable Medical Corporation, the manufacturer of our Isolator clamps, which are an essential part of our Isolator Synergy System. On December 31, 2013, we acquired Endoscopic Technologies, Inc. (Estech), a medical device company focused primarily on RF ablation products. We have two operating subsidiaries: (i) AtriCure Europe B.V., a company incorporated under the laws of the Netherlands in December 2005 and (ii) AtriCure, LLC, a limited liability company organized under the laws of Delaware in October 2012.

Market Overview

Afib is the most commonly diagnosed sustained cardiac arrhythmia, and affects more than 30 million people worldwide, including more than 5 million in the United States, where approximately 160,000 new cases of Afib are diagnosed each year. According to data from the Framingham Heart Study, a study originally undertaken by the National Heart Institute (now known as the National Heart, Lung and Blood Institute), it is estimated that the incidence of Afib doubles with each decade of an adult’s life. At age 40, remaining lifetime risk for Afib is 26% for men and 23% for women. Afib is an under-diagnosed condition due in large part to the fact that patients with Afib often have mild or no symptoms and their Afib is only diagnosed when they seek treatment for an associated condition, such as a stroke or heart disease. We believe that increasing awareness of Afib and improved diagnostic screening will result in an increased number of patients diagnosed with Afib. Also, since the prevalence of Afib increases with age, there will likely be an increase in the number of diagnosed Afib patients in the United States as the population ages.

According to the American Heart Association, people with Afib are about five times more likely to have a stroke, and Afib is thought to be responsible for approximately 15% to 20% of the estimated 700,000 strokes that occur annually in the United States. In a major study of patients with a stroke and Afib, over 90% of the clots identified by imaging were found to exist within the LAA providing evidence that Afib-related stroke is significantly linked with clots arising from the LAA. Afib-related strokes tend to be severe, and approximately

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35% of Afib patients will have a stroke in their lifetime. Studies suggest that 25% of people who have an Afib-related stroke die within the first thirty days following their stroke and over 40% are permanently bedridden. In addition, Afib accounts for $6,700,000 in hospitalization-related costs in the United States. Additional costs include the cost of drugs and indirect costs, such as the management of Afib-related strokes, the costs of which are believed to be significant. Because of this significant cost burden on the healthcare system, we believe that the surgical practice of excluding the LAA has become a growing trend in procedures performed to treat Afib, and current practice guidelines indicate that the LAA should be removed, when possible, during cardiac surgery in patients at risk of developing postoperative Afib. We also believe that our AtriClip system is potentially safer, more effective and easier to use when permanently excluding the LAA than other products and techniques, and, because of this, we believe that the market for the AtriClip system is large and represents a growth opportunity for us.

Afib is a condition that doctors often find difficult to treat and, historically, there has been no widely accepted long-term cure for Afib. Doctors typically begin treating Afib with drugs, which are often ineffective, not well-tolerated and may be associated with serious side effects, including the risk of bleeding. Patients who cannot effectively be treated with drugs may be candidates to undergo catheter-based procedures to treat their Afib. To perform a catheter ablation, an electrophysiologist inserts a flexible catheter into the inside of the heart, typically through the femoral vein. Catheter-based procedures are often technically challenging, can be associated with serious complications, are generally not indicated for a certain population of Afib patients, and have been known to yield inconsistent results. Implantable devices, such as pacemakers and defibrillators, are sometimes used to reduce the frequency and symptoms of Afib although they are not designed to treat the underlying disease. In the past, an open-heart surgical procedure known as the “cut and sew Maze” was used to treat Afib, but this procedure has not been widely adopted because it is technically challenging, highly invasive and involves long recovery times.

Of the patients undergoing open-heart surgery in the United States, we estimate that 80,000-90,000 are potential candidates for surgical ablation using our ablation products. Of the United States population diagnosed with Afib, a large percentage of these patients are symptomatic and do not respond to drug therapy or are intolerant to the drugs used to treat Afib. For these patients, the cut and sew Maze procedure is typically too invasive and catheter ablation may not be indicated. Accordingly, we believe that there is a large population of under-treated patients for whom their physicians may decide that they would potentially benefit from a minimally invasive or hybrid Afib treatment using our Synergy System and related products, and that these patients comprise our largest growth opportunity.

The AtriCure Solution and Products

Competing surgical and catheter-based ablation devices are not ideal for safely, rapidly and reliably creating lesions that completely and permanently block the abnormal electrical impulses that cause Afib, particularly for patients with more chronic forms of Afib or patients who have failed single or multiple catheter ablations. Our products, including our Isolator Synergy System, enable cardiac surgeons to achieve comparable results to the cut and sew Maze procedure but with a faster, less invasive and less technically challenging approach.

Our clinical studies for the use of our products to treat Afib are ongoing. Leading cardiothoracic surgeons and electrophysiologists, including those who serve or who have served as consultants to us, have published results of initial clinical studies utilizing our Isolator Synergy System. The results of these studies are promising in terms of efficacy, ease of use and safety.

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We have three primary product lines for cardiac tissue ablation and a product line for left atrial appendage exclusion:

Product lines for cardiac tissue ablation:

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Product line for left atrial appendage management:

AtriClip System. The AtriClip system is designed to exclude the left atrial appendage by mechanically clamping the appendage from the outside, eliminating blood flow between the left atrial appendage and the atrium while avoiding contact with circulating blood. We believe that the AtriClip system is potentially safer, more effective and easier to use than other currently available products and techniques for permanently excluding the left atrial appendage. The AtriClip portfolio includes a range of devices with different size clips, as well as different applier lengths and deployment features.

In addition to the above product lines we also sell enabling technologies including our Lumitip^™ dissectors and Estech’s line of reusable cardiac surgery instruments. The Lumitip dissector is used by surgeons to separate tissues to provide access to key anatomical structures that are targeted for ablation. The Estech cardiac surgery instruments are used during surgical procedures for repair or replacement of certain heart valves.

Current Afib Treatment Alternatives

Physicians usually begin treating Afib patients with a variety of drugs intended to prevent blood clots, control heart rate or restore the heart to normal sinus rhythm. If a patient’s Afib cannot be adequately controlled with drug therapy, doctors may perform one of several procedures that vary depending on the severity of the Afib symptoms and whether or not the patient suffers from other forms of heart disease. A 2014 report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society set forth guidelines for the management of patients with Afib. The guidelines state:

Treatment alternatives include:

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With the exception of the Isolator Synergy System, which may be promoted according to its FDA-approved indication for patients with persistent and long-standing persistent Afib undergoing certain open-heart procedures, we do not promote our products specifically for Afib. Nevertheless, physicians have adopted our products for use in open-heart and minimally invasive procedures for the treatment of Afib. During elective open-heart surgical procedures, such as bypass or valve surgery, cardiothoracic surgeons use our ablation systems to treat patients with a pre-existing history of Afib. Surgeons report that ablation using our products generally adds approximately 10 to 30 minutes to an open-heart surgical procedure. Surgeons use our products to perform cardiac procedures that may vary depending on the length of time a patient has been diagnosed with Afib and whether the patient’s Afib is intermittent, known as paroxysmal, or more continuous (non-paroxysmal), which is typically further classified as persistent, long-standing persistent or permanent. Patients who have been diagnosed with Afib for a longer duration and have non-paroxysmal forms of Afib generally receive more extensive ablation procedures than patients who have been diagnosed with Afib for a shorter duration or who have paroxysmal Afib. Additionally, during an open-heart procedure, physicians may use our AtriClip system to exclude the left atrial appendage, which has been reported to add less than one minute to a procedure.

For those patients with Afib who do not require a concomitant open-heart surgical procedure, surgeons have used our Isolator clamps and related products for minimally invasive Afib treatment procedures. These procedures have generally been performed through minimally invasive incisions without the need to place patients on a heart-lung bypass machine. Surgeons have reported that the procedure takes approximately two to four hours and that the average hospitalization period has typically been two to five days. Similar to the open-heart surgical procedure, patients who have non-paroxysmal forms of Afib generally require an expanded lesion set that mimics the cut and sew Maze procedure. Our multifunctional pens are often used during these procedures to enable physicians to perform additional ablations.

Physicians are performing an emerging minimally invasive stand-alone, staged procedure which combines epicardial (surgical) ablation (ablation on the outside of the heart) with endocardial ablation and mapping techniques (from the inside of the heart). This procedure involves having the epicardial procedure performed on the first day of hospitalization and the catheter ablation and mapping performed at a later time. Physicians are reporting that they are performing this procedure, also known as a hybrid procedure, utilizing our Isolator clamps and related products in combination with catheter ablation and mapping techniques to primarily treat patients who have non-paroxysmal forms of Afib.

Product Development

Our product development team develops product enhancements and new products to address unmet procedural and market needs with the goal of improving patient care, increasing revenue and optimizing procedural outcomes. Our current product development activity includes projects extending and improving our existing products, the creation of new enabling devices and research into new technologies.

Business Strategy

Our mission is to expand the treatment options for patients who suffer from Afib or have a high risk of stroke through the continued development of our technologies and expansion of our product offerings. The key elements of our strategy include:

Provide Training and Education. We have recruited and trained sales professionals who have strong backgrounds in the medical device industry to effectively communicate to doctors the unique features and benefits of our technologies as they relate to their indications for use. Our highly trained sales professionals meet with doctors at leading institutions around the world to provide education and training on the technical features and benefits of our products. With the approval of our Isolator Synergy System for the treatment of non-paroxysmal Afib, we instituted a program to train providers on the use of the Isolator Synergy System to treat persistent Afib in patients undergoing open-heart surgery. We believe this training and education program will

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increase awareness about the surgical treatment of Afib during open-heart procedures. We also provide medical information on our products in response to information requests from physicians, and we have provided educational grants to institutions that have facilitated the education of doctors concerning the treatment of Afib, including the use of our products as an Afib treatment alternative. As a result of the educational process, we believe that awareness of our technologies is growing and will result in the increased use of our products.

Expand International Markets and Enter into New Markets. Sales to international customers represented 25% of our total revenue for 2014. Many of the international markets in which we currently do business are underpenetrated markets which present high growth opportunities for our products. Further, we plan to continue to evaluate expansion opportunities in new geographic markets and capitalize on new product introductions.

New Product Innovation. We plan to continue to develop new and innovative products, including those that allow us to enter new market opportunities or expand our growth in existing markets. Our product development and growth plans include continued innovation to expand on both new and existing market opportunities through either leveraging our existing product platform or developing entirely new products to serve new markets.

Engage with Key Opinion Leaders. We have formed consulting relationships with cardiothoracic surgeons who work with us to evaluate and develop our products. Additionally, we have formed an advisory board made up of key opinion leaders (KOLs) in cardiac surgery to oversee our surgical training programs. We are also building relationships with physicians in other specialties, including electrophysiology and interventional cardiology, who are involved in the treatment of patients with Afib and thus will provide insight regarding treatment trends, input on future product direction and education for other specialties involved in treating the disease.

Leverage Product Portfolio, Labeling and Cross-Selling Opportunities. We believe we have the most comprehensive offering of cardiac ablation and left atrial appendage exclusion products in the market. We plan to leverage our leading product portfolio to facilitate cross-selling of our products as well as to drive market share gains through competitive account conversions.

Expand Adoption of Our Minimally Invasive Products. We believe that the catalysts for expanded adoption of our minimally invasive products include procedural advancements, such as the hybrid procedure, and the publication of peer-reviewed articles describing long term results from their use in minimally invasive procedures. We also expect that successful completion of several company-sponsored clinical trials, along with FDA approval of expanded indications for the products in those trials, will create increased demand for our minimally invasive products.

Invest in Clinical Trials. We continue to invest in landmark clinical trials to validate the long term results of procedures using our products, and to support applications to regulatory agencies for expanded indications.

Clinical Trials

We received pre-market approval (PMA) for our Isolator Synergy System in December 2011, following successful completion of the ABLATE clinical trial. FDA approved the Isolator Synergy System for the treatment of patients with persistent and long-standing persistent Afib during open-heart concomitant coronary artery bypass grafting and/or valve replacement or repair procedures. The approval included a requirement to conduct a 350-patient post-approval study (PAS). The PAS was designed to evaluate the long-term results of cases using the Isolator Synergy System to treat persistent and long-standing persistent Afib in patients undergoing open-heart procedures. We submitted a protocol for the PAS to FDA in February 2012, and it was approved in September 2012. We submitted a protocol amendment to increase enrollment by up to 40 patients to FDA in April 2014. The amendment was approved in June 2014. Enrollment in the trial was completed in October 2014 with 365 patients at 40 medical centers. We expect to release preliminary data from the study in early 2016, with a complete report expected to be published in 2017.

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We conducted the Dual Epicardial Endocardial Persistent Atrial Fibrillation (DEEP AF) Feasibility clinical trial to evaluate use of the Isolator Synergy System for the treatment of Afib in a two-part procedure where a minimally invasive surgical ablation procedure is performed first, and an intracardiac catheter mapping and ablation procedure is then performed on a different day during the same hospitalization. The Staged DEEP AF Feasibility trial protocol was submitted to FDA in February 2012, and FDA approval to conduct the trial was received in June 2012. Enrollment in the Staged DEEP trial began during the third quarter of 2012 and was completed during the fourth quarter of 2013, with 30 patients enrolled at six medical centers.

We submitted an Investigational Device Exemption (IDE) application for the Staged DEEP pivotal trial to FDA in May 2014. The Staged DEEP pivotal trial evaluates the safety and efficacy of the Isolator Synergy System when used in a staged approach, where a minimally invasive surgical ablation procedure is first performed, and the patient undergoes the intracardiac catheter procedure approximately 90-120 days later. FDA conditional approval was received in July 2014. FDA full approval was received in September 2014. We have approval to enroll up to 220 subjects at 23 domestic medical centers and two international medical centers.

We are also conducting a Stroke Feasibility clinical trial with the AtriClip System. The Stroke Feasibility trial protocol was initially approved by FDA in December 2011. An amendment to the protocol was submitted to FDA and approved in October 2013. The Stroke trial evaluates the initial safety and efficacy of the AtriClip System for stroke prophylaxis (prevention of stroke) in patients with non-valvular Afib in whom long term oral anticoagulation therapy is medically contraindicated. We have approval to enroll up to 30 patients at seven medical centers during the course of the trial. Enrollment began in the first quarter of 2014 and currently stands at eleven patients.

Sales, Marketing and Medical Education

Our United States sales and marketing efforts focus on educating doctors about our unique technologies and their technical benefits. We only promote our products in the United States for uses described in their FDA approved or cleared labeling. We train our sales force on the use of our products to treat Afib to the extent the products are cleared for the treatment of Afib.

Our sales team in the United States is led by a Chief Operating Officer and has approximately 85 employees supporting approximately 45 sales territories. We select our sales personnel based on their expertise, sales experience and reputation in the medical device industry, and their knowledge of cardiac surgery procedures and technologies.

Our sales team in the United States has approximately 85 employees supporting approximately 45 sales territories. We select our sales personnel based on their expertise, sales experience and reputation in the medical device industry and their knowledge of cardiac surgery procedures and technologies.

We market and sell our products in selected markets outside of the United States through independent distributors and through our European subsidiary which includes a combination of independent distributors and direct sales personnel. During 2014 and 2013 sales to customers outside of the United States accounted for 25% and 24% of our total revenue, respectively. We have a network of distributors outside of the United States who currently market and sell our products. They are located primarily in Europe, Asia, South America and Canada. Our international sales team includes sales representatives who sell to customers in markets we sell directly to, such as Germany, France, the United Kingdom and the Benelux region. We continue to evaluate opportunities for further expansion into markets outside of the United States.

Competition

Our industry is competitive, subject to change and significantly affected by new product introductions and other activities of industry participants. Many of our competitors have significantly greater financial and human resources than we do and have established reputations with our target customers, as well as worldwide

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distribution channels that are more established and developed than ours. Our primary competitor is Medtronic, Inc. We and our competitors provide products that have been adopted by doctors for the treatment of Afib and related conditions. Several of our competitors offer intracardiac catheter devices that are commonly used by electrophysiologists to treat Afib. Some of these catheter devices are FDA-approved to treat the paroxysmal form of Afib, but they are not FDA-approved to treat persistent or long-standing persistent Afib. AtriCure’s Isolator Synergy System is the only medical device FDA approved to treat Afib in a surgical setting, and the only medical device approved to treat persistent or long-standing persistent Afib in any form.

We believe that our products compare favorably against competing products that are commonly used for the surgical treatment of Afib during both open-heart and sole-therapy minimally invasive procedures, although we cannot assume that we will be able to continue to do so in the future or that new devices that perform better than our products will not be introduced. We also believe that our products compare favorably to intracardiac catheter devices when used to treat non-paroxysmal forms of Afib. Further, we believe our AtriClip system is superior to all other medical devices indicated for exclusion of the left atrial appendage.

Due to the size of the Afib and left atrial appendage exclusion markets, and the unmet need for an Afib cure, competitors have dedicated and will continue to dedicate significant resources to develop and market their products. New product developments that could compete with us more effectively are likely because the Afib treatment and left atrial appendage exclusion markets are characterized by extensive research efforts and technological progress.

Existing or new competitors may develop technologies and products that are safer, more effective, easier to use or less expensive than our products. To compete effectively, we have to demonstrate that our products are an attractive alternative to other treatments by differentiating our products on the basis of safety, efficacy, performance, ease of use, reputation, service and price. We have encountered and expect to continue to encounter potential customers who prefer products offered by our competitors. Competitive pressures may result in price reductions and reduced gross profit margins for our products over time. Technological advances may render our products obsolete or uneconomical.

Third-Party Reimbursement

Payment for patient care in the United States is generally made by third-party payors. These payors include private insurers and government insurance programs, such as Medicare and Medicaid. The Medicare program, the largest single payor in the United States, is a federal health benefit program administered by the Centers for Medicare and Medicaid Services (CMS), and covers certain medical care items and services for eligible beneficiaries, such as individuals over 65 years old, as well as chronically disabled individuals. Reimbursement under Part A of the Medicare program includes hospitals and other institutional services, while Medicare Part B covers physician services. Because Medicare beneficiaries comprise a large percentage of the populations for which our products are used, and private insurers may follow the coverage and payment policies for Medicare, Medicare’s coding, coverage and payment policies for cardiothoracic surgical procedures are significant to our business.

Medicare’s Part A program pays hospitals for inpatient services, such as cardiothoracic surgery, under the Inpatient Prospective Payment System (IPPS) which provides a predetermined payment based on the patient’s discharge diagnoses and surgical procedure(s). Discharge diagnoses are grouped into Medicare Severity Diagnosis Related Groupings (MS-DRG). There are several cardiac surgery MS-DRGs associated with the surgical treatment of Afib, with and without a concomitant open-heart procedure. When an ablation device and/or LAA exclusion device is used during a concomitant open-heart procedure, Medicare’s hospital reimbursement is based upon the patient’s primary surgical procedure. Reimbursement for sole-therapy minimally invasive Afib ablation treatment is also influenced by the patient’s severity of illness. Currently, we believe hospital reimbursement rates for sole therapy and concomitant therapy cardiac surgical tissue ablation are adequate to cover the cost of our products. Medicare’s coding, coverage, and payment policies are subject to change. As a

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result, the continuance of current coverage, coding or payment determinations cannot be guaranteed, and any change may have an adverse impact on our business.

Doctors are reimbursed for their services separately under the Medicare Part B physician fee schedule. When surgically performing a cardiac ablation with and without a concomitant open-heart procedure, surgeons report Current Procedural Terminology (CPT) codes to receive a professional fee. Surgeons have a choice of CPT codes to report sole-therapy and concomitant therapy cardiac tissue ablation. At this time, there are no CPT codes for the physician to report surgical exclusion of the left atrial appendage.

In addition to the Medicare program, many private payors look to CMS policies as a guideline in setting their coverage policies and payment amounts. The current coverage policies of these private payors may differ from the Medicare program, and payment rates may be higher, lower, or the same as the Medicare program. If CMS or other agencies decrease or limit reimbursement payments to doctors and hospitals, this may negatively impact our business. Additionally, some private payors do not follow the Medicare guidelines and those payors may reimburse only a portion of the cost of cardiac ablation, or not at all. Physicians, in combination with their professional organizations and societies, are responding and working to secure reimbursement for the procedure to the extent the payor has denied reimbursement.

FDA does not regulate the practice of medicine. Doctors may use our products in circumstances where they deem it medically appropriate, such as for the treatment of Afib or the reduction in stroke risk, even though FDA may not have approved or cleared our products to be marketed specifically for those indications. Some payors may deem the use of our products for indications not specifically approved or cleared by FDA to be experimental and, as such, may deny coverage or payment.

Outside of the United States, third-party reimbursement varies widely by geography and by the type of therapy in which our devices are used. For example, even though a new medical device may have been approved for commercial distribution, we may find limited demand for the device until coverage and sufficient reimbursement levels have been obtained from governmental and private third-party payers. In addition, some private third-party payers require that certain procedures or the use of certain products be authorized in advance as a condition of reimbursement. In certain markets outside of the United States, cost containment initiatives and health care reforms include initiatives like governmental reviews of reimbursement rate benchmarks, which may significantly reduce reimbursement for procedures using our medical devices or deny coverage for those procedures.

Government Regulation

Our products are medical devices and are subject to regulation in the United States by FDA and other federal agencies, and comparable authorities in other countries. In December 2011, following FDA approval of the new indication, we began to market the Isolator Synergy System for the treatment of patients with persistent and long-standing persistent Afib during open-heart concomitant surgical procedures such as coronary artery bypass grafting (CABG) and valve replacement or repair. The Isolator Synergy System was previously 510(k) cleared for the ablation of cardiac tissue, and continues to be marketed in the United States under both the 510(k) clearance and PMA approval. Our minimally invasive clamps are 510(k) cleared for the ablation of cardiac tissue. Our multifunctional pen and multifunctional linear pen are 510(k) cleared for temporary pacing, sensing, stimulating and recording during the evaluation of cardiac arrhythmias and for the ablation of cardiac tissue. Our cryoablation products are 510(k) cleared for the treatment of cardiac arrhythmias. Our CRYO2 probes received an additional 510(k) clearance in December 2014 for blocking pain by temporarily ablating peripheral nerves. The Lumitip dissector is 510(k) cleared for use in the dissection of soft tissues during general, ear, nose and throat, thoracic, urological and gynecological surgical procedures. The AtriClip system is 510(k) cleared for occlusion of the left atrial appendage under direct visualization in conjunction with other open cardiac surgical procedures. The Estech Fusion Ablation System is 510(k) cleared to ablate cardiac tissue and for temporary cardiac pacing, sensing, recording and stimulation during the evaluation of cardiac arrhythmias. The AFfirm

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Bipolar Pacing Probe is 510(k) cleared to provide transient cardiac pacing or recording for the assessment of electrical isolation/conduction block of ablation lesions in the surgical treatment of arrhythmias.

FDA regulations govern nearly all of the activities that we perform, or that are performed on our behalf, to ensure that medical products distributed domestically or exported internationally are safe and effective for their intended uses. The activities that the FDA regulates include the following:

FDA’s Premarket Clearance and Approval Requirements. Unless an exemption applies, most medical devices distributed commercially in the United States will require either prior 510(k) clearance or PMA from the FDA. Other premarket pathways, such as the humanitarian device exemption (HDE) or a request for classification under section 513(a)(1) of the FDCA, commonly known as a de novo request, are also available in certain situations. Medical devices are classified into one of three classes—Class I, Class II, or Class III—depending on the degree of risk and the level of control necessary to assure the safety and effectiveness of each medical device. Devices deemed to pose lower risks are placed in either Class I or II. While most Class I devices are exempt from the requirement to submit a 510(k) notification requesting clearance to commercially distribute the device, most Class II devices are subject to the 510(k) premarket notification process. Devices deemed by the FDA to pose the greatest risk, such as life-sustaining, life-supporting or implantable devices, or devices deemed not substantially equivalent to a previously cleared 510(k) device or predicate device, are generally placed in Class III, requiring submission of a PMA supported by clinical trial data.

510(k) Clearance Pathway. When 510(k) clearance is required, we must submit a notification to the FDA demonstrating that our proposed device is substantially equivalent to a predicate device, i.e., a previously cleared and legally marketed 510(k) device or a device that was in commercial distribution before May 28, 1976 for which the FDA has not yet called for the submission of a PMA. The FDA is required to respond to a 510(k) notification within 90 days of submission, but the response may be a request for additional information or data, including clinical data. As a practical matter, 510(k) clearance often takes significantly longer than 90 days and may take up to a year or more. If the FDA determines that the device, or its intended use, is not substantially equivalent to a previously cleared device or use, the device is automatically placed into Class III, requiring the submission of a PMA. Any modification to a 510(k)-cleared device that would constitute a major change in its intended use, design or manufacture, requires a new 510(k) clearance or, possibly, in connection with safety and effectiveness, approval of a PMA. The FDA requires every manufacturer to make the determination regarding a new 510(k) submission in the first instance, but the FDA may review any manufacturer’s decision. We have made modifications to elements of our products which we believe did not require us to seek additional 510(k) clearance.

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Premarket Approval Pathway. A PMA must be submitted to the FDA if the device cannot be cleared through the 510(k) process and is not otherwise exempt. A PMA must be supported by extensive data, including but not limited to technical, preclinical, clinical, manufacturing and labeling, to demonstrate the safety and effectiveness of the device for its intended use.

After a PMA is submitted and the FDA has determined that the application is sufficiently complete to permit a substantive review, the FDA will accept the application for filing. The FDA has 180 days to review an “accepted” PMA, although the review of an application generally occurs over a significantly longer period of time and can take up to several years. During this review period, the FDA may request additional information or clarification of the information already provided. Also, an advisory panel of experts from outside the FDA may be convened to review and evaluate the application and provide recommendations to the FDA as to the approvability of the device. In addition, the FDA will conduct a preapproval inspection of the manufacturing facility to ensure compliance with quality system regulations. Any approvals we receive may be limited in scope or may be contingent upon further post-approval study commitments or other conditions. New PMAs or PMA supplements are required for significant modification to the device, including indicated use, manufacturing process, labeling and design of a device that is approved through the premarket approval process. PMA supplements often require submission of the same type of information as a PMA, except that the supplement is limited to information needed to support any changes from the device covered by the original PMA and may not require as extensive clinical data or the convening of an advisory panel.

Clinical Trials. Clinical trials are required to support a PMA and are sometimes required for 510(k) clearance. In the United States, clinical trials for a significant risk device require the prior submission of an application for an IDE to the FDA for approval. An IDE application must be submitted before initiating a new clinical study. Some trials require a feasibility study followed by a pivotal trial. An IDE supplement is utilized as a means of obtaining approval to initiate a pivotal trial following the conclusion of a feasibility trial. IDE applications must be supported by appropriate data, such as animal and laboratory testing results, and any available data on human clinical experience, showing that it is safe to test the device in humans and that the testing protocol is scientifically sound. The animal and laboratory testing must meet the FDA’s good laboratory practice requirements.

The IDE and any IDE supplement for a new trial must be approved in advance by the FDA. Clinical trials for significant risk devices may not begin until the IDE application is approved by the FDA and each center’s Institutional Review Board (IRB) overseeing the welfare of the research subjects and responsible for that particular clinical trial. If the product is considered a non-significant risk device under FDA regulations, only the center’s IRB approval is required. Under its regulations, the agency responds to an IDE application (amendment or supplement) for a new trial within 30 days. The FDA may approve the IDE unconditionally, grant an approval with certain conditions, or identify deficiencies that must be addressed prior to the approval of the study. It is common for the FDA to require additional information before approving an IDE, and thus final FDA approval on a submission commonly extends beyond the initial 30 days. The FDA may also require that a small-scale feasibility study be conducted before a pivotal trial may commence. In a feasibility trial, the FDA limits the number of patients and centers that may participate. Feasibility trials are typically structured to obtain information on safety and to evaluate the clinical efficacy to determine the number of subjects required to demonstrate statistical significance in a pivotal trial.

Clinical trials are subject to extensive recordkeeping and reporting requirements. Our clinical trials must be conducted under the oversight of an IRB for the relevant clinical trial sites and must comply with FDA regulations, including, but not limited to, those relating to current good clinical practices. We are also required to obtain the written informed consent of patients in form and substance that complies with both FDA requirements and state and federal privacy and human subject protection regulations. We, the FDA or the IRB may suspend a clinical trial at any time for various reasons, including a belief that the risks to study subjects outweigh the anticipated benefits. Even if a trial is completed, the results of clinical testing may not adequately demonstrate the safety and efficacy of the device or may otherwise not be sufficient to obtain FDA approval to market the

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product in the United States. Similarly, in Europe, the clinical study must be approved by a local ethics committee and, in some cases, including studies with high-risk devices, by the ministry of health in the applicable country.

Educational Grants. FDA regulates manufacturers of medical devices and, in particular, the promotion of medical devices by manufacturers. FDA does not regulate the practice of medicine or the conduct or content of medical education conducted by third parties. Manufacturers may provide financial support for such third-party medical education programs in the form of educational grants intended to offset the cost of such programs. If the manufacturer controls or unduly influences the content of such programs, FDA considers those programs to be promotional activities by the manufacturer and thus subject to FDA regulation including promotional restrictions.

FDA considers several factors in determining whether an educational event or activity is independent from the substantive influence of the device manufacturer, including, but not necessarily limited to, the following:

We seek to ensure that the activities we support pursuant to our educational grants program are in accordance with these criteria for independent educational activities. However, we cannot provide an assurance that the FDA or other government authorities would view the programs we have supported as being independent.

Pervasive and Continuing Regulation. There are numerous regulatory requirements that apply after a product is cleared or approved. These include:

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Under FDA’s MedWatch regulation, we must submit a Medical Device Report (MDR) to FDA within 30 days whenever we receive information that reasonably suggests that one of our products may have caused or contributed to a death or serious injury, or that one of our products malfunctioned in a manner which, if the malfunction were to recur, could cause or contribute to a death or serious injury. Our products are often used to treat very ill patients in highly complex surgeries, only a small portion of which may involve our products, and it is frequently difficult to determine whether our products caused or contributed to a patient injury or death that occurred during or after the procedure. If we are unable to determine whether our product caused or contributed to a death or serious injury in the particular case, or that a malfunction of the type reported would not cause death or serious injury, we submit an MDR on the case. Other incidents, including serious injuries or deaths, which occurred during procedures utilizing our products and that are not the subject of MDRs, may occur either because we are not aware of those incidents or because our investigation determined that the incident did not involve a malfunction of an AtriCure device and/or that an AtriCure device did not cause or contribute to a serious injury or death.

In addition to FDA regulation, the advertising and promotion of medical devices are also regulated by the Federal Trade Commission and by state regulatory and enforcement authorities. Recently, some promotional activities for FDA-regulated products have been the subject of enforcement action brought under healthcare reimbursement laws and consumer protection statutes. In addition, under the Federal Lanham Act and similar state laws, competitors and others can initiate litigation relating to advertising claims.

We have registered with the FDA as a medical device manufacturer and listed our devices. The FDA has broad post-market and regulatory enforcement powers. We are subject to unannounced inspections by the FDA and our Notified Body to determine our compliance with the QSR, the European Union’s Medical Device Directive (MDD) and other regulations, and these inspections may include the manufacturing facilities of our suppliers.

Failure by us or by our suppliers to comply with applicable regulatory requirements can result in enforcement action by the FDA or other federal or state authorities, which may include any of the following sanctions, among others:

Fraud, Abuse and False Claims. We are directly and indirectly subject to various federal and state laws governing our relationship with healthcare providers and pertaining to healthcare fraud and abuse, including anti-kickback laws. In particular, the federal healthcare program Anti-Kickback Statute prohibits persons from knowingly and willfully soliciting, offering, receiving or providing remuneration, directly or indirectly, in exchange for or to induce either the referral of an individual, or the furnishing, arranging for or recommending a good or service for which payment may be made in whole or part under federal healthcare programs, such as the Medicare and Medicaid programs. Penalties for violations include criminal penalties and civil sanctions such as fines, imprisonment and possible exclusion from Medicare, Medicaid and other federal healthcare programs. The Anti-Kickback Statute is broad and prohibits many arrangements and practices that are lawful in businesses outside of the healthcare industry. In implementing the statute, the Office of Inspector General of the U.S. Department of Health and Human Services (OIG) has issued a series of regulations, known as the “safe harbors.”

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These safe harbors set forth provisions that, if all their applicable requirements are met, will assure healthcare providers and other parties that they will not be prosecuted under the Anti-Kickback Statute. The failure of a transaction or arrangement to fit precisely within one or more safe harbors does not necessarily mean that it is illegal or that prosecution will be pursued. However, conduct and business arrangements that do not fully satisfy each applicable element of a safe harbor may result in increased scrutiny by government enforcement authorities, such as the OIG.

The Federal False Claims Act (FCA) imposes civil liability on any person or entity that submits, or causes the submission of, a false or fraudulent claim to the United States Government. Damages under the FCA can be significant and consist of the imposition of fines and penalties. The FCA also allows a private individual or entity with knowledge of past or present fraud against the federal government to sue on behalf of the government to recover the civil penalties and treble damages. The U.S. Department of Justice, or DOJ, on behalf of the government, has previously alleged that the marketing and promotional practices of pharmaceutical and medical device manufacturers included the off-label promotion of products or the payment of prohibited kickbacks to doctors violated the FCA resulting in the submission of improper claims to federal and state healthcare entitlement programs such as Medicaid. In certain cases, manufacturers have entered into criminal and civil settlements with the federal government under which they entered into plea agreements, paid substantial monetary amounts and entered into corporate integrity agreements that require, among other things, substantial reporting and remedial actions going forward.

The Advanced Medical Technology Association (AdvaMed) is one of the primary voluntary United States trade associations for medical device manufacturers. This association has established guidelines and protocols for medical device manufacturers in their relationships with healthcare professionals on matters including research and development, product training and education, grants and charitable contributions, support of third-party educational conferences, and consulting arrangements. Adoption of the AdvaMed Code by a medical device manufacturer is voluntary, and while the OIG and other federal and state healthcare regulatory agencies encourage its adoption and may look to the AdvaMed Code, they do not view adoption of the AdvaMed Code as proof of compliance with applicable laws. We have adopted the AdvaMed Code and incorporated its principles in our standard operating procedures, sales force training programs, and relationships with doctors. Key to the underlying principles of the AdvaMed Code is the need to focus the relationships between manufacturers and healthcare professionals on matters of training, education and scientific research, and limit payments between manufacturers and healthcare professionals to fair market value for legitimate services provided and payment of modest meal, travel and other expenses for a healthcare professional under limited circumstances. We have incorporated these principles into our relationships with healthcare professionals under our consulting agreements, payment of travel and lodging expenses, grant making procedures and sponsorship of third-party conferences. In addition, we have conducted training sessions on these principles. However, we cannot provide any assurance that regulatory or enforcement authorities will view these arrangements as being in compliance with applicable laws.

Regulation Outside of the United States. Sales of medical devices outside of the United States are subject to foreign governmental regulations which vary substantially from country to country. The time required to obtain certification or approval by a foreign country may be longer or shorter than that required for FDA clearance or approval and the requirements may be different.

In the European Union, various directives and voluntary standards regulate the design, manufacture and labeling of and clinical trials and adverse event reporting for medical devices. Devices may only be placed in the market in the European Union if they comply with the essential requirements of a relevant directive and bear the CE mark. Manufacturers must demonstrate that their devices comply with the relevant essential requirements through a conformity assessment procedure. The method for assessing conformity varies depending on the type and class of the product, but normally involves a combination of self-assessment by the manufacturer and a third-party assessment by a notified body, an independent and neutral institution appointed by a country to conduct the conformity assessment. This third-party assessment will include a review of documentation relating to the device

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and may consist of an audit of the manufacturer’s quality system and specific testing of the manufacturer’s device. Successful completion of a conformity assessment procedure allows a manufacturer to issue a declaration of conformity with the requirements of the relevant directive and affix the CE mark to the device. Devices that bear the CE mark may be commercially distributed throughout the member states of the European Union and other countries that comply with or mirror the medical device directives. A notified body has granted us a certificate of compliance with the International Organization for Standardization, (ISO) 13485:2003 Quality Management System. Compliance with this standard establishes the presumption that our quality system conforms with the essential requirements or the relevant directive. We have successfully completed the conformity assessment procedure and affixed the CE Mark to our Isolator Synergy clamps, allowing us to commercialize those clamps in the European Union for the treatment of cardiac arrhythmias, including atrial fibrillation. Our Isolator Synergy pens, Coolrail linear pen and Isolator Synergy Access clamps are CE Marked to ablate soft tissue. Our Isolator linear pen is CE marked to ablate cardiac tissue and temporarily pace, sense, record, and stimulate during evaluation of cardiac arrhythmias. Our cryosurgery devices are CE Marked for the treatment of cardiac arrhythmias. Our AtriClip LAA Exclusion System is CE marked for occlusion of the heart’s left atrial appendage. Our Fusion Ablation System is CE marked for the treatment of cardiac arrhythmias, such as atrial fibrillation, by coagulating cardiac tissue involved in the conduction of the arrhythmia. The Fusion System is also intended for use in the treatment of atrial fibrillation, by ablating cardiac tissue involved in the conduction of the arrhythmia and to provide transient cardiac pacing, sensing, recording and stimulation for the assessment of electrical isolation / conduction block of ablation lesions in the surgical treatment of arrhythmias. The AFfirm Bipolar Pacing Probe is CE marked to provide transient cardiac pacing or recording for the assessment of electrical isolation / conduction block of ablation lesions in the surgical treatment of cardiac arrhythmias.

Intellectual Property

Protection of our intellectual property is a strategic priority for our business and we rely on a combination of patent, copyright, trademark and trade secret laws to protect our interests. Our ability to protect and use our intellectual property rights in the continued development and commercialization of our technologies and products, operate without infringing the proprietary rights of others, and prevent others from infringing our proprietary rights is crucial to our continued success. We will be able to protect our products and technologies from unauthorized use by third parties only to the extent that they are covered by valid and enforceable patents, trademarks or copyrights or are effectively maintained as trade secrets, know-how or other proprietary information.

We hold numerous issued United States and international patents. We also have multiple pending United States and international patent applications. We seek patent protection relating to technologies and products we develop in both the United States and in selected foreign countries. While we own much of our intellectual property, including patents, patent applications, trademarks, trade secrets, know-how and proprietary information, we also license patents and related technology of importance to the commercialization of our products. For example, to continue developing and commercializing our current and future products, we may license intellectual property from commercial or academic entities to obtain the rights to technology that is required for our research, development and commercialization activities.

All of our employees and technical consultants are required to execute confidentiality agreements in connection with their employment and consulting relationships with us. We also generally require them to agree to disclose and assign to us all inventions conceived in connection with their relationship with us. We cannot provide any assurance that employees and consultants will abide by the confidentiality or assignment terms of these agreements. Despite measures taken to protect our intellectual property, unauthorized parties might copy aspects of our products or obtain and use information that we regard as proprietary. We devote significant resources to obtaining patents and other intellectual property and protecting our other proprietary information. If valid and enforceable, these patents may give us a means of blocking competitors from using infringing technology to compete directly with our products. We also have certain proprietary trade secrets that may not be patentable or for which we have chosen to maintain secrecy rather than file for patent protection. With respect to

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proprietary know-how that is not patentable, we have chosen to rely on trade secret protection and confidentiality agreements to protect our interests.

Manufacturing

We manufacture a majority of the disposable and implantable products we sell and generally purchase items that would be deemed capital equipment, including the ASU, ASB, ESU and the ORLab cardiac monitoring system. We inspect, assemble, test and package the majority of our products in West Chester, Ohio, and our products are sterilized by third-parties. Purchased components are generally available from more than one supplier. However, some products, such as our ASU, ESU and ASB, are critical components of our RF ablation lines and there are relatively few alternative sources of supply available. We generally carry a six-month supply of these products, however, obtaining a replacement supplier for the ASU, ESU and ASB, if required, may not be accomplished quickly or at all and could involve significant additional costs. Generally, our suppliers have no contractual obligations to supply us with, and we are not contractually obligated to purchase any of our supplies from them.

Order quantities and lead times for components purchased from outside suppliers are based on our forecasts derived from historical demand and anticipated future demand. Lead times may vary significantly depending on the size of the order, time required to fabricate and test the components, specific supplier requirements and current market demand for the components and subassemblies. To date, we have not experienced significant delays in obtaining any of our components. There are no unique or proprietary processes required in manufacturing our components. We generally do not have contractual obligations that preclude us from developing products or sourcing components from new suppliers.

We and our component suppliers are required to manufacture our products in compliance with the FDA’s QSR. The QSR regulates extensively the methods and documentation of the design, testing, control, manufacturing, labeling, quality assurance, packaging, storage and shipping of our products. The FDA enforces the QSR through periodic inspections that may be announced or unannounced and may include the manufacturing facilities of our suppliers. Our failure or the failure of our suppliers to maintain compliance with the QSR requirements could result in the shutdown of our manufacturing operations or the recall of our products, which would have a material adverse effect on our business. In the event that one of our suppliers fails to maintain compliance with our quality requirements, we may have to qualify a new supplier and could experience manufacturing delays as a result. We also could be subjected to injunctions, product seizures, or civil or criminal penalties.

We regularly audit our suppliers for compliance with QSR and applicable ISO standards. We have been an FDA-registered medical device manufacturer since November 2002. We obtained our CE Mark in June of 2002, and our quality systems and facility practices are certified to ISO 13485:2003; MDD 93/42/EEC, or CE Mark, and CMDCAS, or Canadian regulations. We believe that we are currently in good standing with the FDA. Our current quality system is developed to comply with QSR and ISO standards.

We are subject to numerous federal, state and local laws relating to such matters as laboratory practices, the experimental use of animals, the use and disposal of hazardous or potentially hazardous substances, safe working conditions, manufacturing practices, environmental protection and fire hazard control. We may incur significant costs to comply with those laws and regulations now or in the future, but, as we currently believe we are in compliance with such laws and regulations, we do not expect that continued compliance will have a material impact on our business.

Consulting Relationships

We have developed consulting relationships with scientists and physicians throughout the world to support our research and development, clinical and training and education programs. We work closely with these thought leaders to understand unmet needs and emerging applications for the treatment of Afib.

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Our physician consulting agreements are intended to satisfy the requirements of the personal services “Safe Harbor” regulation as well as the AdvaMed and EucoMed Codes. As such, they provide for payment of a fair market value fee only for legitimate services actually rendered to us. We do not expect or require the consultant to utilize or promote our products, and consultants are required to disclose their relationship with us as appropriate, such as when publishing an article in which one of our products is discussed. Amounts paid to U.S. physicians are disclosed by us in annual reports submitted to CMS under the federal “Open Payments” law and implementing regulations and under similar U.S. state and international laws, rules and regulations.

Royalty Agreements

We have certain royalty agreements in place with terms that include payment of royalties based on product revenue from sales of specified current products. The royalty agreements have effective dates as early as 2003 and terms ranging from three years to at least twenty years. The royalties range from 0.75% to 5% of specified product sales. One of the agreements includes minimum quarterly payments of $50 through 2015 and a maximum of $2,000 in total royalties over the term of the agreement. Parties to the royalty agreements have the right at any time to terminate the agreement immediately for cause. Royalty expense for each of the years ended December 31, 2014, 2013 and 2012 was $1,322, $962 and $603, respectively.

Employees

We had approximately 320 full-time employees as of January 31, 2015. None of the employees were represented by a labor union or covered by a collective bargaining agreement. We have never experienced any employment-related work stoppages and consider our employee relations to be good although we cannot provide any assurance that we will not experience such work stoppages in the future.

Available Information

Our principal executive offices are located at 6217 Centre Park Drive, West Chester, Ohio and our telephone number is 513-755-4100. We are subject to the reporting requirements under the Securities Exchange Act of 1934. Consequently, we are required to file reports and information with the Securities and Exchange Commission, or SEC, including reports on the following forms: Form 10-K, Form 10-Q, Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934. These reports and other information concerning us may be accessed through the SEC’s website at http://www.sec.gov. You may also find, free of charge, on our website at http://www.atricure.com, electronic copies of our Form 10-Ks, Form 10-Qs, Form 8-Ks, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934. Such filings are placed on our website as soon as reasonably practicable after they are filed or furnished, as the case may be, with the SEC. Our charters for our Audit, Compensation and Nominating and Corporate Governance Committees and our Code of Ethics are available on our website. In the event that we grant a waiver under our Code of Ethics to any of our officers and directors, we will publish it on our website. Information contained in any of our websites is not deemed to be a part of this Form 10-K.

Risks Relating To Our Business

If our products do not achieve widespread market acceptance in the United States, our operating results will be harmed and we may not achieve profitability.

Our success will depend, in large part, on the medical community’s acceptance of our principal products in the United States, which is the largest revenue market in the world for medical devices. The U.S. medical community’s acceptance of our products will depend upon our ability to demonstrate the safety and efficacy, advantages, long-term clinical performance and cost-effectiveness of our products as compared to other products.

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In addition, acceptance of products for the treatment of Afib is dependent upon, among other factors, the level of screening for Afib and the awareness and education of the medical community about the surgical treatment of Afib, in general, and the existence, effectiveness and, in particular, the safety of our products. Market acceptance and adoption of our products for the treatment of Afib also depends on the level of reimbursement to doctors and hospitals for the use of our products.

We cannot predict whether the U.S. medical community will accept our products or, if accepted, the extent of their use. Negative publicity resulting from isolated incidents involving our products or other products related to those we sell could have a significant adverse effect on the overall acceptance of our products. If we encounter difficulties developing a market for our products in the United States, we may not be able to increase our revenue enough to achieve profitability, and our business and operating results will be seriously harmed.

We rely on our ablation, ablation-related and AtriClip products as our primary sources of revenue. If we are not successful in selling these products, or if these products become obsolete, our operating results will be harmed.

Our ablation products, such as our clamps and related products, along with our left atrial appendage clip products, generate a large majority of our revenue. We expect that sales of these products will continue to account for a majority of our revenue for the foreseeable future and that our future revenue will depend on the increasing acceptance by the medical community of our products as a standard treatment alternative for the surgical treatment of Afib during open-heart surgical procedures and as a sole-therapy minimally invasive procedure. We may not be able to maintain or increase market acceptance of our products for a number of additional reasons, including those set forth elsewhere in this “Risk Factors” section. In addition, our products may become obsolete prior to the end of their anticipated useful lives or we may introduce new products or next-generation products prior to the end of the useful life of a prior generation, either of which may require us to dispose of existing inventory and related capital instruments and/or write off their value or accelerate their depreciation. Since we believe that doctors are using our ablation and ablation-related products only for the surgical treatment of Afib, if doctors do not use our products to treat Afib, we would lose substantially all of our revenue.

Worldwide economic conditions may reduce demand for procedures using our products or otherwise result in adverse implications on our business, operating results and financial condition.

General worldwide economic conditions may deteriorate due to the effects of, among other developments, general credit market crises, collateral effects on the finance and banking industries, concerns about inflation, slower economic activity, decreased consumer confidence, reduced corporate profits and capital spending, adverse business conditions and liquidity concerns. We are unable to predict the extent to which current or future worldwide economic conditions may impact our business. Specifically, because many procedures using our products are elective, they can be deferred by patients. In addition, patients may not be as willing under current or future economic conditions to take time off from work or spend their money on deductibles and co-payments often required in connection with the procedures that use our products.

Beyond patient demand, any current or future deterioration in worldwide economic conditions, including in particular their effects on the credit and capital markets, may have other adverse implications for our business. For example, our customers’ ability to borrow money from their existing lenders or to obtain credit from other sources to purchase our products may be impaired resulting in a decrease in sales. Although we maintain allowances for estimated losses resulting from the inability of our customers to make required payments, we cannot guarantee that we will accurately predict the loss rates we will experience, especially given any continuing turmoil in the worldwide economy. A significant change in the liquidity or financial condition of our customers could cause unfavorable trends in our receivable collections and additional allowances may be required, which could adversely affect our operating results. Further, given the economic and political challenges facing Eurozone countries, concerns have been raised regarding the stability and suitability of the Euro as a single currency. The failure of the Euro as a single currency could adversely affect our operating results.

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Healthcare costs have risen significantly over the past decade. There have been and may continue to be proposals by legislators, regulators and third-party payors to keep, contain or reduce healthcare costs.

The continuing efforts of governments, insurance companies and other payors of healthcare costs to contain or reduce these costs, combined with closer scrutiny of such costs, could lead to patients being unable to obtain approval for payment from these third-party payors. The cost containment measures that healthcare providers are instituting both in the U.S. and internationally could harm our business. Some healthcare providers in the U.S. have adopted or are considering a managed care system in which the providers contract to provide comprehensive healthcare for a fixed cost per person. Healthcare providers may attempt to control costs by authorizing fewer elective surgical procedures or by requiring the use of the least expensive devices possible, which could adversely affect the demand for our products or the price at which we can sell our products. Some healthcare providers have sought to consolidate and create new companies with greater market power, including hospitals. As the healthcare industry consolidates, competition to provide products and services has become and will continue to become more intense. This has resulted and likely will continue to result in greater pricing pressures and the exclusion of certain suppliers from important marketing segments.

We face significant uncertainty in the industry due to government healthcare reform.

The Patient Protection and Affordable Care Act, as amended, (Patient Act) as well as other healthcare reform have a significant impact on our business. The impact of the Patient Act on the healthcare industry is extensive and includes, among other things, the federal government assuming a larger role in the healthcare system, expanding healthcare coverage of United States citizens and mandating basic healthcare benefits. The Patient Act has impacted our business by requiring an excise tax on all U.S. medical device sales beginning in January 2013. The increased tax burden will have a significant impact on our results of operations and cash flows. Any healthcare reforms enacted in the future may, like the Patient Act, be phased in over a number of years but, if enacted, could reduce our revenue, increase our costs or require us to revise the ways in which we conduct business or put us at risk for loss of business. In addition, our results of operations, financial position and cash flows could be materially adversely affected by changes under the Patient Act and changes under any federal or state legislation adopted in the future.

Our quarterly financial results are likely to fluctuate significantly because our sales prospects are uncertain.

Due to current worldwide economic conditions and other factors discussed in this “Risk Factors” section which may impact our sales results, our quarterly operating results are difficult to predict and may fluctuate significantly from quarter to quarter or from prior year to current year periods, particularly because our sales prospects are uncertain. These fluctuations may also affect our annual operating results and may cause those results to fluctuate unexpectedly from year to year.

Restrictions in our ability to train doctors in the use of our products could reduce the market acceptance of our products or result in injuries to patients or other adverse events that could possibly lead to litigation that could harm us or could reduce our revenue.

It is critical to the success of our sales efforts to ensure that there are a sufficient number of doctors familiar with, trained on and proficient in the use of our products. While we train providers in the safe and effective use of our products, we do not train them to use any of our products specifically to treat Afib unless the product is FDA-approved specifically for the treatment of Afib. In December 2011 our Isolator Synergy System was approved for the treatment of persistent and long standing persistent forms of Afib concomitant to open heart bypass graft or valve replacement surgery. The procedure using our Isolator Synergy System in this manner is known as the MAZE IV^™ procedure. Following approval, we instituted a program to train all new and existing users of the Isolator Synergy System in the MAZE IV procedure. We also make available training on the safe and effective use of our other products consistent with their FDA approved or cleared indications. We cannot assure you that a sufficient number of doctors will become aware of training programs or that doctors will dedicate the time, funds and energy necessary to obtain training for themselves or to train others in the use of our products.

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Unless and until we obtain additional FDA approval for our products, we will not be able to promote many of our products to treat Afib or to prevent stroke, and our ability to maintain and grow our business could be harmed.

Although our Isolator Synergy System received FDA approval for the treatment of some forms of Afib in certain procedures, we have not received FDA clearance or approval to promote our other products for the treatment of Afib or the prevention of stroke. See “Business—Government Regulation.” Unless and until we obtain FDA clearance or approval for the use of our products to treat Afib or prevent stroke, we, and others acting on our behalf, may not claim in the U.S. that our products are safe and effective for such uses or otherwise promote them for such uses. We cannot assure you that future clearances or approvals of our products will be granted or that current or future clearances or approvals will not be withdrawn. Failure to obtain a clearance or approval or loss of an existing clearance or approval, could hurt our ability to maintain and grow our business.

Unless and until we are able to complete the clinical trials required to support future submissions to the FDA, and unless and until the data generated by such trials supports the use of our products as safe and effective for the treatment of Afib or reduction in stroke risk, we may not be able to secure additional FDA approvals and our ability to maintain and grow our business could be harmed.

In order to obtain additional FDA approvals to promote our products for the treatment of Afib or reduction in stroke risk, we will need to demonstrate in clinical trials that our products are safe and effective for such use. Development of sufficient and appropriate clinical protocols to demonstrate quality, safety and efficacy may be required and we may not adequately develop such protocols to support approval. We cannot assure you that any of our clinical trials will be completed in a timely manner or successfully or that the results obtained will be acceptable to the FDA. In addition, if the results obtained from our clinical trials, any other clinical studies, or clinical or commercial experience indicate that any of our products are not safe or effective, or not as safe or effective as other treatment options, the FDA may not approve our products for the treatment of Afib or reduction in stroke risk, adoption of the use of our products may suffer and our business would be harmed.

Our clinical trials are typically time consuming and expensive and the outcome uncertain. Delays in patient enrollment or failure of patients to consent or continue to participate in a clinical trial may cause an increase in costs and delays in the approval and attempted commercialization of our products or result in the failure of the clinical trial. Conducting successful clinical studies may require the enrollment of large numbers of clinical sites and patients, and suitable patients may be difficult to identify and recruit. Patient enrollment in clinical trials and completion of patient participation and follow-up depends on many factors, including the size of the patient population, the nature of the trial protocol, the attractiveness of, or the discomforts and risks associated with, the treatments received by enrolled subjects, the availability of appropriate clinical trial investigators, support staff, and proximity of patients to clinical sites and ability to comply with the eligibility and exclusion criteria for participation in the clinical trial and patient compliance. For example, patients may be discouraged from enrolling in our clinical trials if the trial protocol requires them to undergo extensive post-treatment procedures or follow-up to assess the safety and effectiveness of our products or if they determine that the treatments received under the trial protocols are not attractive or involve unacceptable risks or discomforts. Patients may also not participate in our clinical trials if they choose to participate in contemporaneous clinical trials of competitive products or they can obtain the treatment without participating in our trial.

We may experience unfavorable publicity relating to our business and our industry. This publicity could have a negative impact on our ability to attract and retain customers, our sales, clinical studies involving our products, our reputation and our stock price.

We may experience a negative impact on our business from newspaper articles or other media reports relating to, among other things, our compliance with FDA regulations for medical device reporting and concerns over disclosure of financial relationships between us and certain of our consultants who are involved with clinical studies and the publication of articles concerning our products. We believe that such publicity would potentially

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have a negative impact on our clinical studies, business, results of operations and financial condition or cause other adverse effects, including a decline in the price of our stock.

We may be subject to fines, penalties, injunctions and other sanctions if we are deemed to be promoting the use of our products for unapproved, or “off-label,” uses.

Our business and future growth depend on the continued use of our products for the treatment of Afib or prevention of stroke. Unless the products are approved or cleared by FDA specifically for the treatment of Afib or prevention of stroke, we may not make claims about the safety or effectiveness of our products for such uses.

These limitations present a material risk that the FDA or other federal or state law enforcement authorities could determine that the nature and scope of our sales, marketing and/or product support activities, though designed to comply with all FDA requirements, constitute the promotion of our products for an unapproved use in violation of the FDCA. We also face the risk that the FDA or other governmental authorities might pursue enforcement based on past activities that we have discontinued or changed, including sales activities, arrangements with institutions and doctors, educational and training programs and other activities. Investigations concerning the promotion of unapproved uses and related issues, including our settlement with the DOJ (see further discussion in Item 3, “Legal Proceedings” of this Form 10-K), are typically expensive, disruptive and burdensome and generate negative publicity. If our promotional activities are found to be in violation of the law, we may face significant fines and penalties and may be required to substantially change our sales, promotion, grant and educational activities. There is also a possibility that we could be enjoined from selling some or all of our products for any unapproved use. In addition, as a result of an enforcement action against us or our executive officers, we could be excluded from participation in government healthcare programs such as Medicare and Medicaid. Also, our failure to comply with the terms of the settlement agreement with the DOJ or the related corporate integrity agreement could result in additional action by the DOJ or the OIG, in fines or penalties or in restrictions on our sales, promotion, grant or educational activities.

The use of products we sell may result in injuries or other adverse events that lead to product liability suits, which could be costly to our business or our customers’ businesses.

The use of products we sell may result in a variety of serious complications, including damage to the heart, internal bleeding, death or other adverse events, potentially leading to product liability claims. Serious complications, including death, are commonly encountered in connection with the surgical treatment of Afib. If products we sell are defectively designed, manufactured or labeled, contain inadequate warnings, contain defective components or are misused, we may become subject to litigation by our customers or their patients. We carry product liability insurance that is limited in scope and amount and may not be adequate to fully protect us against product liability claims. We could be required to pay damages that exceed our insurance coverage. Any product liability claim, with or without merit, could result in an increase in our product insurance rates or our inability to secure coverage on reasonable terms, if at all. Even in the absence of a claim, our insurance rates may rise in the future. Any product liability claim, even a meritless or unsuccessful one, would be time-consuming and expensive to defend and could result in the diversion of our management’s attention from our business and result in adverse publicity, withdrawal of clinical trial participants, injury to our reputation and loss of revenue. Any of these events could negatively affect our earnings and financial condition.

Competition from existing and new products and procedures may decrease our market share and cause our revenue to decline.

The medical device industry, including the market for the treatment of Afib, is highly competitive, subject to rapid technological change and significantly affected by new product introductions and promotional activities of its participants. We cannot assure you that our products will compete effectively against drugs, catheter-based ablation, implantable devices, other ablation systems, other products or techniques to exclude the left atrial appendage, or other surgical Afib treatments, which may be more well-established among doctors and hospitals.

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We anticipate that new or existing competitors may develop competing products, procedures and/or clinical solutions. There are few barriers to prevent new entrants or existing competitors from developing products to compete directly with ours. Some companies also compete with us to attract qualified scientific and technical personnel as well as funding. Some of our competitors have greater financial, manufacturing, marketing and research and development capabilities than we have or may obtain FDA approval for the use of their products before we do. The introduction of new products, procedures, clinical solutions or our competitors obtaining FDA approvals may result in price reductions, reduced margins or loss of market share and may render our products obsolete, which could adversely affect our net revenue and future profitability.

Our intellectual property rights may not provide meaningful commercial protection for our products, which could enable third-parties to use our technology or methods, or very similar technology or methods, and could reduce our ability to compete.

Our success depends significantly on our ability to protect our proprietary rights to the technologies used in our products. We rely on patent protection, as well as a combination of copyright, trade secret and trademark laws and nondisclosure, confidentiality and other contractual restrictions to protect our proprietary technology. However, these legal means afford only limited protection and may not adequately protect our rights or permit us to gain or keep any competitive advantage. Our patent applications may not issue as patents at all or in a form that will be advantageous to us. Our issued patents and those that may be issued in the future may be challenged, invalidated or circumvented, which could limit our ability to stop competitors from marketing related products. Although we have taken steps to protect our intellectual property and proprietary technology, we cannot assure you that third-parties will not be able to design around our patents or, if they do infringe upon our technology, that we will be successful in or will have sufficient resources to pursue a claim of infringement against those third-parties. We believe that third-parties may have developed or are developing products that could infringe upon our patent rights. Any pursuit of an infringement claim by us may involve substantial expense or diversion of management attention. In addition, although we have generally entered into confidentiality agreements and intellectual property assignment agreements with our employees, consultants, investigators and advisors, such agreements may be breached, may not be enforceable or may not provide meaningful protection for our trade secrets or other proprietary information in the event of unauthorized use or disclosure or other breaches of the agreements. Additionally, as is common in the medical device industry, some of these individuals were previously employed at other medical equipment or biotechnology companies, including our competitors. Although no claims are currently pending against us, we may be subject to claims that these individuals or we have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers.

Furthermore, the laws of foreign countries may not protect our intellectual property rights to the same extent as the laws of the United States. Foreign countries generally do not allow patents to cover methods for performing surgical procedures. If our intellectual property does not provide significant protection against foreign or domestic competition, our competitors could compete more directly with us, which could result in a decrease in our market share. All of these factors may harm our competitive position.

The medical device industry is characterized by extensive litigation and administrative proceedings over patent and other intellectual property rights and any litigation or claim against us may cause us to incur substantial costs, could place a significant strain on our financial resources, divert the attention of management from our business and harm our reputation.

Whether a product infringes a patent involves complex legal and factual issues, the determination of which is often uncertain. Any patent dispute, even one without merit or an unsuccessful one, would be time-consuming and expensive to defend and could result in the diversion of our management’s attention from our business and result in adverse publicity, the disruption of development and marketing efforts, injury to our reputation and loss of revenue. Litigation also puts our patent applications at risk of being rejected and our patents at risk of being invalidated or interpreted narrowly, and may provoke third parties to assert claims against us. Any of these events could negatively affect our earnings and financial condition.

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In the event of a patent dispute, if a third-party’s patents were upheld as valid and enforceable and we were found to be infringing, we could be prevented from selling our products unless we were able to obtain a license to use technology or ideas covered by such patent or are able to redesign our system to avoid infringement. A license may not be available at all or on terms acceptable to us, and we may not be able to redesign our products to avoid any infringement. Modification of our products or development of new products could require us to conduct additional clinical trials and to revise our filings with the FDA and other regulatory bodies, which would be time-consuming and expensive. If we are not successful in obtaining a license or redesigning our products, we may be unable to sell our products and our business could suffer.

The increase in cost of medical malpractice premiums to doctors and hospitals or the lack of malpractice insurance coverage due to the use of our products by doctors for an off-label indication may cause certain doctors or hospitals to decide not to use our products and may damage our ability to grow and maintain the market for our system.

Insurance carriers have been raising premiums charged for medical malpractice insurance due, at least in part, to increased risks associated with off-label procedures, including higher damage awards for successful plaintiffs. Insurance carriers may continue to raise premiums or they may deny malpractice coverage for procedures performed using products such as ours on an off-label basis. If this trend continues or worsens, our revenue may fall as doctors or hospitals decide against purchasing our products due to the cost or unavailability of insurance coverage.

We have a history of net losses and we may never become profitable.

We have incurred net losses each year since our inception, including net losses of $16,211 in 2014, $11,462 in 2013, $7,534 in 2012, $5,456 in 2011, $3,792 in 2010, $16,495 in 2009, $10,167 in 2008, $11,253 in 2007, $13,717 in 2006 and $12,683 in 2005. As of December 31, 2014, we had an accumulated deficit of $138,424.

Our net losses have resulted principally from costs and expenses relating to sales and promotional efforts, research and development, seeking regulatory clearances and approvals, goodwill impairment, litigation and settlement costs associated with the DOJ investigation and general operating expenses. We expect to continue to make substantial expenditures and to potentially incur additional operating losses in the future as we further develop and commercialize our products, including completing clinical trials and seeking regulatory clearances and approvals. If sales of our products do not continue to grow as we anticipate, we will not be able to achieve profitability. Our expansion efforts may prove more expensive than we currently anticipate, and we may not succeed in increasing our revenue sufficiently to offset these higher expenses. Our losses have had, and are expected to continue to have, an adverse impact on our working capital, total assets and accumulated deficit and we may never become profitable.

Our federal tax net operating loss and general business credit carryforwards generated prior to the initial public offering of our common stock will be limited or may expire, which could result in greater future income tax expense and adversely impact future cash flows because we experienced an ownership change of more than 50 percentage points upon the initial public offering of our common stock. Additionally, the Company acquired net operating losses in the purchase of Estech which may be limited or may expire.

In connection with our initial public offering in August 2005, we experienced an ownership change as defined by Section 382 of the Internal Revenue Code of 1986. Section 382 imposes limitations (Section 382 limitation) on a company’s ability to use net operating loss and general business credit carryforwards if a company experiences a more-than-50-percent ownership change over a three-year testing period. Additionally, in connection with the Company’s acquisition of Estech additional acquired NOLs are also subject to Section 382 limitation. The Section 382 limitation could limit the availability of our net operating loss and general business credit carryforwards to offset any future taxable income, which may increase our future income tax expense and

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adversely impact future cash flows. We had total federal income tax net operating loss and general business credit carryforwards that, if not utilized to reduce our taxable income, will begin to expire in 2019. The Company has generated additional net operating loss and general business credit carryforwards of $147,398 and $4,395, respectively, which, if not utilized to reduce our taxable income, will begin to expire in 2019.

Our capital needs after the next 12 months are uncertain and we may need to raise additional funds in the future and such funds may not be available on acceptable terms, if at all.

We believe that our current cash, cash equivalents and investments, including additional cash generated from public offerings of common stock in January 2013 and February 2014 along with the cash we expect to generate or use for operations or access via our revolving credit facility will be sufficient to meet our projected capital requirements for at least the next 12 months. The January 2013 common stock offering generated $26,872 in net proceeds through the issuance of 3,996,250 shares, and the February 2014 common stock offering generated $65,850 in net proceeds through the issuance of 3,660,525 shares. Our current loan agreement (Agreement) with Silicon Valley Bank (SVB), as amended, includes a revolving credit facility under which we can borrow a maximum of $15,000. We can borrow the lesser of the amount available pursuant to a borrowing base formula and $15,000 under the revolving credit facility. Based on our current borrowing base, we have availability of approximately $12,383. The Agreement is secured by specified assets, including intellectual property. The revolving credit facility matures on April 30, 2016.

We may be unable to comply with the covenants of our credit facility.

Our Agreement contains covenants that include, among others, covenants that limit our ability to dispose of assets, enter into mergers or acquisitions, incur indebtedness, incur liens, pay dividends or make distributions on our capital stock, make investments or loans, and enter into certain affiliate transactions, in each case subject to customary exceptions for a credit facility of this size and type. Additional covenants apply when we have outstanding borrowings under the revolving loan facility or when we achieve specific covenant milestones. The occurrence of an event of default could result in an increase to the applicable interest rate by 3.0%, an acceleration of all obligations under the Agreement, an obligation to repay all obligations in full, and a right by the Bank to exercise all remedies available to it under the Agreement and related agreements including the Guaranty and Security Agreement. If we are unable to pay those amounts, the Bank could proceed against the collateral granted to it pursuant to the credit facility.

If we need to raise additional funds, we cannot be certain that such funds will be available to us on acceptable terms, if at all. Furthermore, if we issue equity securities to raise additional funds, our existing stockholders may experience dilution, and if we issue equity or debt securities, such securities may have rights, preferences and privileges senior to those of our existing stockholders. In addition, if we raise additional funds through collaboration, licensing or other similar arrangements, it may be necessary to relinquish potentially valuable rights to our future products or proprietary technologies, or grant licenses on terms that are not favorable to us. If we cannot raise funds on acceptable terms, we may not be able to expand our operations, develop new products, take advantage of future opportunities or respond to competitive pressures or unanticipated customer requirements.

We rely upon single and limited source third-party suppliers and third-party logistics providers, making us vulnerable to supply problems and price fluctuations which could harm our business.

We currently rely on single and limited source third-party vendors for the manufacture of many of the components used in our products. For example, we rely on one vendor to manufacture our ASU, ESU and ASB. It would be a time consuming and lengthy process to secure these products from an alternative supplier. In addition, in some cases there are relatively few alternative sources of supply for certain other components that are critical to our products. We also rely on a third party to handle our warehousing and logistics functions for European and Middle Eastern markets on our behalf.

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Our reliance on outside manufacturers and suppliers also subjects us to risks that could harm our business, including:

Identifying and qualifying additional or replacement suppliers for any of the components used in our products or a replacement warehousing and logistics provider, if required, may not be accomplished quickly and could involve significant additional costs. Any interruption or delay in the supply of components, materials or warehousing and logistics, or our inability to obtain components or materials from alternate sources at acceptable prices in a timely manner, could impair our ability to meet the demand of our customers and cause them to cancel orders or switch to competitive products and could therefore have a material adverse effect on our business, financial condition and results of operations.

If the value of our goodwill becomes impaired, it could materially reduce the value of our assets and increase our net loss for the year in which the write-off occurs.

As of December 31, 2014, we had $35,386 in goodwill related to the Estech acquisition, which represents the excess purchase price we paid for the purchase of Estech in excess of the fair value of the net assets we acquired. The Financial Accounting Standards Board’s (FASB) Accounting Standards Codification (ASC) 350, “Goodwill and Other Intangible Assets” requires that goodwill be tested at least annually (absent any impairment indicators). The testing includes comparing the fair value of each reporting unit with its carrying value. Fair value is determined using discounted cash flows, market multiples and market capitalization. Impairment adjustments, if any, are required to be recognized as operating expenses. We may have future impairment adjustments to our recorded goodwill. Any finding that the value of our goodwill has been impaired would require us to write off the impaired portion, which could materially reduce the value of our assets and reduce our net income for the year in which the write off occurs.

An inability to forecast future revenue or estimate life cycles of products may result in inventory-related charges that would negatively affect our gross margins and results of operations.

To mitigate the risk of supply interruptions, we may choose to maintain excess inventory of our products or component parts. Managing our inventory levels is important to our cash position and results of operations and is more challenging in the current economic environment. As we grow and expand our product offerings, managing our inventory levels becomes more difficult, particularly as we expand into new product areas and bring product enhancements to market. While we rely on our information technology systems for inventory management and to effectively manage accounting and financial functions, our information technology systems may fail to adequately perform these functions or may experience an interruption. An excessive amount of inventory reduces our cash available for operations and may result in excess or obsolete materials. Conversely, inadequate inventory levels may make it difficult for us to meet customer product demand, resulting in decreased revenue. An inability to forecast future revenue or estimated life cycles of products may result in inventory-related charges that would negatively affect our gross margins and results of operations.

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If we or our third-party vendors fail to comply with extensive FDA regulations relating to the manufacturing of our products or any component part, we may be subject to fines, injunctions and penalties, and our ability to commercially distribute and sell our products may be hurt.

Our manufacturing facility and the manufacturing facility of any of our third-party component manufacturers, critical suppliers or third-party sterilization facility are required to comply with the FDA’s Quality System regulation (QSR) which sets forth minimum standards for the procedures, execution and documentation of the design, testing, production, control, quality assurance, labeling, packaging, sterilization, storage and shipping of the products we sell. The FDA may evaluate our compliance with the QSR, among other ways, through periodic announced or unannounced inspections which could disrupt our operations and interrupt our manufacturing. If in conducting an inspection of our manufacturing facility or the manufacturing facility of any of our third-party component manufacturers, critical suppliers or third-party sterilization facility, an FDA investigator observes conditions or practices believed to violate the QSR, the investigator may document their observations on a Form FDA-483 that is issued at the conclusion of the inspection. A manufacturer that receives an FDA-483 may respond in writing and explain any corrective actions taken in response to the inspectional observations. The FDA will typically review the facility’s written response and may re-inspect to determine the facility’s compliance with the QSR and other applicable regulatory requirements. Failure to take adequate and timely corrective actions to remedy objectionable conditions listed on an FDA-483 could result in the FDA taking administrative or enforcement actions. Among these may be the FDA’s issuance of a Warning Letter to a manufacturer, which informs it that the FDA considers the observed violations to be of “regulatory significance” that, if not corrected, could result in further enforcement action. FDA enforcement actions, which include seizure, injunction and criminal prosecution, could result in total or partial suspension of a facility’s production and/or distribution, product recalls, fines, suspension of the FDA’s review of product applications and the FDA’s issuance of adverse publicity. Thus, an adverse inspection could force a shutdown of our manufacturing operations or a recall of our products. Adverse inspections could also delay FDA approval of our products and could have an adverse effect on our production, sales and profitability.

We and any of our third-party vendors may also encounter other problems during manufacturing including failure to follow specific protocols and procedures, equipment malfunction and environmental factors, any of which could delay or impede our ability to meet demand. The manufacture of our product also subjects us to risks that could harm our business, including problems relating to the sterilization of our products or facilities and errors in manufacturing components that could negatively affect the efficacy or safety of our products or cause delays in shipment of our products. Any interruption or delay in the manufacture of the product or any of its components could impair our ability to meet the demand of our customers and cause them to cancel orders or switch to competitive products and could, therefore, have a material adverse effect on our business, financial condition and results of operations.

If we fail to comply with the extensive FDA regulations relating to our business, we may be subject to fines, injunctions and penalties and our ability to commercially distribute and promote our products may be hurt.

Our products are classified by the FDA as medical devices and, as such, are subject to extensive regulation in the United States by the FDA and numerous other federal, state and foreign governmental authorities. FDA regulations, guidance, notices and other issuances specific to medical devices are broad and regulate, among other things:

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Compliance with FDA, state and other regulations can be complex, expensive and time-consuming. The FDA and other authorities have broad enforcement powers. Furthermore, changes in the applicable governmental regulations could prevent further commercialization of our products and technologies and could materially harm our business.

If a serious failure to comply with applicable regulatory requirements was determined, it could result in enforcement action by the FDA or other state or federal agencies, including the DOJ, which may include any of the following sanctions, among others:

If any of these events were to occur, we could lose customers and our production, product sales, business, results of operations and financial condition would be harmed.

We are also subject to medical device reporting regulations that require us to file reports with the FDA if our products reasonably are the cause of or contribute to an adverse event, death, serious injury or, in the event of product malfunction, that if it were to recur, would likely cause or contribute to a death or serious injury. We have a history of submitting medical device reports to the FDA involving our products, including patient deaths, which were categorized as outcomes based on physician judgment, not on the failure of our devices. There have also been other incidents, including patient deaths, which have occurred during procedures using our products that we have not, and believe were not required to be, reported to the FDA because we and our physician consultants determined that our products did not cause or contribute to the outcomes in these incidents. If the FDA disagrees with us, however, and determines that we should have submitted reports for these adverse events, we could be subject to significant regulatory fines or other penalties. In addition, the number of medical device reports we make, or the magnitude of the problems reported, could cause the FDA or us to terminate or modify our clinical trials or recall or cease the sale of our products, and could hurt commercial acceptance of our products.

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Modifications to our products may require new clearances or approvals or require us to cease promoting or to recall the modified products until such clearances or approvals are obtained and the FDA may not agree with our conclusions regarding whether new clearances or approvals were required.

Any modification to a 510(k)-cleared device that would constitute a change in its intended use, design or manufacture, could require a new 510(k) clearance or, possibly, submission and FDA approval of a PMA. The FDA requires every medical device company to make the determination as to whether a new 510(k) is to be filed, but the FDA may review any medical device company’s decision. We have made modifications to our products but do not believe such modifications required us to submit an additional 510(k). The FDA may not agree with our decisions regarding whether new clearances or approvals were required.

If the FDA were to disagree with us and require us to submit a new 510(k), PMA or a different type of PMA supplement for then existing modifications, we could be required to cease promoting or to recall the modified product until we obtain clearance or approval. In addition, we could be subject to significant regulatory fines or other penalties. Furthermore, our products could be subject to recall if the FDA determines, for any reason, that our products are not safe or effective or that appropriate regulatory submissions were not made. Delays in receipt or failure to receive clearances or approvals, the loss of previously received clearances or approvals, or the failure to comply with existing or future regulatory requirements, could reduce our sales, profitability and future growth prospects.

We will spend considerable time and money complying with federal, state and foreign regulations in addition to FDA regulations, and, if we are unable to fully comply with such regulations, we could face substantial penalties.

We are subject to extensive regulation by the federal government and foreign countries in which we conduct business. The laws that affect our ability to operate our business in addition to the FDCA and FDA regulations include, but are not limited to, the following:

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Healthcare fraud and abuse regulations are complex, and even minor, inadvertent irregularities can potentially give rise to claims that a law has been violated. Any violations of these laws could result in a material adverse effect on our business, financial condition and results of operations. For example, if we were found to be in violation of the Federal False Claims Act, we would likely face significant fines and penalties and would likely be required to change substantially our sales, promotion, grant and educational activities. There is also a possibility that we could face an injunction that would prohibit in whole or in part our current business activities, and, as a result of enforcement actions against us or our senior officers, we could be excluded from participation in government healthcare programs such as Medicare and Medicaid. If there is a change in law, regulation or administrative or judicial interpretations, we may have to change our business practices or our existing business practices could be challenged as unlawful, which could have a material adverse effect on our business, financial condition and results of operations. In October 2008, DOJ initiated an investigation of the marketing and promotional practices of several companies with surgical ablation products. Both AtriCure and Estech were among the companies subject to that investigation. Although neither AtriCure nor Estech admitted wrongdoing, and both believed there was no wrongdoing on the part of it or its employees, during 2010 this investigation resulted in financial settlements with both companies, and both companies entered into corporate integrity agreements that provided certain ongoing compliance and reporting obligations.

If our past or present operations are found to be in violation of any of the laws described above or the other governmental regulations to which we, our distributors or our customers are subject, we may be subject to the applicable penalty associated with the violation, including civil and criminal penalties, damages, fines, exclusion from Medicare, Medicaid and other government programs and the curtailment or restructuring of our operations. If we are required to obtain permits or licensure under these laws that we do not already possess, we may become subject to substantial additional regulation or incur significant expense. Any penalties, damages, fines, curtailment or restructuring of our operations would adversely affect our ability to operate our business and our financial results. The risk of our being found in violation of these laws is increased by the fact that many of them have not been fully or clearly interpreted by the regulatory authorities or the courts, and their provisions are subject to a variety of interpretations and additional legal or regulatory change. Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses, divert our management’s attention from the operation of our business and damage our reputation.

Adverse changes in payors’ policies toward coverage and reimbursement for surgical Afib treatment would harm our ability to promote and sell our products.

Third-party payors are increasingly exerting pressure on medical device companies to reduce their prices. Even to the extent that the use of our products is reimbursed by private payors and governmental payors, adverse changes in payors’ policies toward coverage and reimbursement for surgical Afib treatment would also harm our ability to promote and sell our products. Payors continue to review their policies and can, without notice, deny coverage for treatments that include the use of our products. Because each third-party payor individually approves coverage and reimbursement, obtaining these approvals may be time-consuming and costly. In addition, third-party payors may require us to provide scientific and clinical support for the use of our products. Adverse changes in coverage and reimbursement for surgical Afib treatment could harm our business and reduce our revenue.

We have traditionally had limited long-term clinical data regarding the safety and efficacy of our products. Any long-term data that is generated may not be positive or consistent with our limited short-term data, which would affect the rate at which our products are adopted by the medical community.

Important factors upon which the efficacy of our products will be measured include long-term data on the number of patients that experience Afib or stroke following treatment with our products and the number of patients that have serious complications resulting from ablations or LAA occlusion using our products. While we believe we are now well-positioned to provide sufficient long-term data regarding the safety and efficacy of our products going forward, such data could, nevertheless, identify unexpected safety issues. We cannot provide any

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assurance that the data collected during our clinical trials will be compelling to the medical community because it may not be scientifically meaningful and may not demonstrate that procedures utilizing our products are an attractive option when compared against data from alternative procedures and products. In addition, the long-term effects of ablation procedures and left atrial appendage exclusion are not well-known. Negative long-term data would affect the use of our products and harm our business and prospects.

We sell our products outside of the United States and we are subject to various regulatory and other risks relating to international operations, which could harm our international revenue and profitability.

Doing business outside of the United States exposes us to risks distinct from those we face in our domestic operations. For example, our operations outside of the United States are subject to different regulatory requirements in each jurisdiction where we operate or have sales. Our failure, or the failure of our distributors, to comply with current or future foreign regulatory requirements, or the assertion by foreign authorities that we or our distributors have failed to comply, could result in adverse consequences, including enforcement actions, fines and penalties, recalls, cessation of sales, civil and criminal prosecution, and the consequences could be disproportionate to the relative contribution of our international operations to our results of operations. Moreover, if political or economic conditions deteriorate in these countries, or if any of these countries are affected by a natural disaster or other catastrophe, our ability to conduct our international operations or collect on international accounts receivable could be limited and our costs could be increased, which could negatively affect our operating results. Engaging in business outside of the United States inherently involves a number of other difficulties and risks, including, but not limited to:

In addition, our business practices in foreign countries comply with U.S. law, including the Foreign Corrupt Practices Act (FCPA). We have a compliance program in place designed to reduce the likelihood of potential violations of the FCPA and other U.S. and foreign anti-bribery and anti-corruption laws. If violations were to occur, they could subject us to fines and other penalties as well as increased compliance costs.

Our exposure to each of these risks may increase our costs and require significant management attention. We cannot assure you that one or more of these factors will not harm our business.

Fluctuations in foreign currency exchange rates could result in declines in our reported sales and results of operations.

Because some of our international sales are denominated in local currencies and not in U.S. dollars, our reported sales and earnings are subject to fluctuations in foreign currency exchange rates, primarily the Euro. We translate results of transactions denominated in local currencies into U.S. dollars using market conversion rates

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applicable to the period in which the transaction is reported. As a result, changes in exchange rates during a period can unpredictably and adversely affect our consolidated operating results and our asset and liability balances, even if the underlying value of the item in its original currency has not changed. At present, we do not hedge our exposure to foreign currency fluctuations. As a result, sales and expenses occurring in the future that are denominated in foreign currencies may be translated into U.S. dollars at less favorable rates, resulting in reduced revenues and earnings.

Our manufacturing operations are primarily conducted at a single location, and any disruption at our manufacturing facility could increase our expenses and decrease our revenue.

Most of our manufacturing operations are conducted at a single location in West Chester, Ohio. While we take precautions at this location, we do not maintain a backup manufacturing facility, making us dependent on our current facility for the continued operation of our business. A natural or other disaster could damage or destroy our manufacturing equipment and cause substantial delays in our manufacturing operations, which could lead to additional expense and decreased revenue due to lack of supply. The insurance we maintain may not be adequate to cover our losses in any particular case. With or without insurance, damage to our facility or our other property, due to a natural disaster or casualty event, could have a material adverse effect on our business, financial condition and results of operations.

We rely on independent distributors to market and sell our products in certain markets outside of the United States, and a failure of our independent distributors to successfully market our products in these markets or any disruption in their ability to do so may adversely impact our sales.

We depend on third-party distributors to sell our products in certain markets outside of the United States and if these distributors do not perform, we may be unable to increase or maintain our level of international revenue. Over the long term, we intend to continue to grow our business outside of the United States, and to do so we will need to attract additional distributors or hire direct sales personnel to expand the territories in which we sell our products. Independent distributors may terminate their relationship with us or devote insufficient sales efforts to our products. We are not able to control our independent distributors, and they may not be successful in implementing our marketing plans. In addition, many of our independent distributors outside of the United States initially obtain and maintain foreign regulatory approval for sale of our products in their respective countries. Our failure to maintain our relationships with our independent distributors outside of the United States, or our failure to recruit and retain additional skilled independent distributors in these locations, could have an adverse effect on our operations. Turnover among our independent distributors, even if replaced, may adversely affect our short-term financial results while we transition to new independent distributors or direct personnel. Fluctuations in foreign currency exchange rates including, in particular, any strengthening of the U.S. dollar may cause our independent sales distributors to seek longer payment terms to offset the higher prices they are paying in local currency for our products. The ability of these third-party distributors to market and sell our products could also be adversely affected by unexpected events, including, but not limited to, power failures, nuclear events, natural or other disasters and war or terrorist activities. In addition, in light of the worldwide economic crisis, the ability of our distributors to borrow money from their existing lenders or to obtain credit from other sources to purchase our products may be impaired or our distributors could experience a significant change in their liquidity or financial condition, all of which could impair their ability to distribute our products and eventually lead to distributor turnover.

If coverage and adequate levels of reimbursement from governmental and third-party payors outside of the United States are not attained and maintained, sales of our products outside of the United States may decrease and we may fail to achieve or maintain significant sales outside of the United States.

Our revenue generated from sales outside of the United States is also dependent upon the availability of coverage and reimbursement within prevailing foreign healthcare payment systems. In general, foreign healthcare payors do not provide reimbursement for sole-therapy minimally invasive procedures utilizing

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ablation devices and related products. In addition, healthcare cost containment efforts similar to those we face in the United States are prevalent in many of the other countries in which we sell our products, and these efforts are expected to continue. To the extent that the use of ablation devices such as our Isolator Synergy clamps has historically received reimbursement under a foreign healthcare payment system, such reimbursement, if any, has typically been significantly less than the reimbursement provided in the United States. If coverage and adequate levels of reimbursement from governmental and third-party payors outside of the United States are not obtained and maintained, sales of our products outside of the United States may decrease and we may fail to achieve or maintain significant sales outside of the United States.

If we fail to properly manage our anticipated growth, our business could suffer.

We may experience periods of rapid growth and expansion, which could place a significant strain on our personnel, information technology systems and other resources. In particular, the increase in our direct sales force requires significant management and other supporting resources. Any failure by us to manage our growth effectively could have an adverse effect on our ability to achieve our development and commercialization goals.

To achieve our revenue goals, we must successfully increase production output as required by customer demand. In the future, we may experience difficulties in increasing production, including problems with production yields and quality control, component supply and shortages of qualified personnel. These problems could result in delays in product availability and increases in expenses. Any such delay or increased expense could adversely affect our ability to generate revenues.

Future growth will also impose significant added responsibilities on management, including the need to identify, recruit, train and integrate additional employees. In addition, rapid and significant growth will place a strain on our administrative and operational infrastructure.

In order to manage our operations and growth we will need to continue to improve our operational and management controls, reporting and information technology systems and financial internal control procedures. If we are unable to manage our growth effectively, it may be difficult for us to execute our business strategy and our operating results and business could suffer.

We depend on our officers and other skilled and experienced personnel to operate our business effectively. If we are not able to retain our current employees or recruit additional qualified personnel, our business will suffer and our future revenue and profitability will be impaired.

We are highly dependent on the skills and experience of our President and Chief Executive Officer, Michael H. Carrel, and certain other officers and key employees. We do not have any insurance in the event of the death or disability of our key personnel. Our officers and key employees, with the exception of our President and Chief Executive Officer, Senior Vice President, Operations and Quality and Vice President and General Manager, International, do not have employment agreements and they may terminate their employment and work elsewhere without notice and without cause or good reason. Currently we have non-compete agreements with our officers and other employees. Due to the specialized knowledge of each of our officers with respect to our products and our operations and the limited pool of people with relevant experience in the medical device field, the loss of service of one or more of these individuals could significantly affect our ability to operate and manage our business. The announcement of the loss of one or more of our key personnel could negatively affect our stock price.

We depend on our scientific and technical personnel for successful product development and innovation, which are critical to the success of our business. In addition, to succeed in the implementation of our business strategy, our management team must rapidly execute our sales strategy, obtain expanded FDA clearances and approvals, achieve market acceptance for our products and further develop products, while managing anticipated growth by implementing effective planning, manufacturing and operating processes. Managing this growth will

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require us to attract and retain additional management and technical personnel. We rely primarily on direct sales employees to sell our products in the United States and failure to adequately train them in the use and benefits of our products will prevent us from achieving our market share and revenue growth goals. We have key relationships with doctors that involve procedure, product, market and clinical development. If any of these doctors end their relationship with us, our business could be negatively impacted. We cannot assure you that we will be able to attract and retain the personnel and doctor relationships necessary to grow and expand our business and operations. If we fail to identify, attract, retain and motivate these highly skilled personnel and doctors, we may be unable to continue our development and sales activities.

Compliance with environmental laws and regulations may be expensive. Failure to comply with environmental laws and regulations could subject us to significant liability.

Our manufacturing operations and research and development activities involve the use of biological materials and hazardous substances and are subject to a variety of federal, state and local environmental laws and regulations relating to the storage, use, discharge, disposal, remediation of, and human exposure to, hazardous substances. Our research and development and manufacturing operations may produce biological waste materials, such as animal tissues and certain chemical waste. These operations are permitted by regulatory authorities and the resultant waste materials are disposed of in material compliance with environmental laws and regulations. Compliance with these laws and regulations may be expensive and non-compliance could result in substantial liabilities. In addition, we cannot completely eliminate the risk of accidental contamination or injury to third parties from the use, storage, handling or disposal of these materials. In the event of contamination or injury, we could be held liable for any resulting damages, and any liability could exceed any applicable insurance coverage we may have. In addition, our manufacturing operations may result in the release, discharge, emission or disposal of hazardous substances that could cause us to incur substantial liabilities, including costs for investigation and remediation.

Our business growth strategy involves the potential for significant acquisitions, which involve risks and difficulties in integrating potential acquisitions and may adversely affect our business, results of operations and financial condition.

All acquisitions involve inherent uncertainties, which may include, among other things, our ability to:

We may acquire businesses with unknown liabilities, contingent liabilities or internal control deficiencies. We have plans and procedures in place to conduct reviews of potential acquisition candidates for compliance with applicable regulations and laws prior to acquisition. Despite these efforts, realization of any of these liabilities or deficiencies may increase our expenses, adversely affect our financial position through the initiation, pendency or outcome of litigation or otherwise, or cause us to fail to meet our public financial reporting obligations.

We have recently consummated a significant acquisition, and in the future may continue to invest a substantial amount of capital in acquisitions. We continue to evaluate potential acquisition opportunities to support, strengthen and grow our business. There can be no assurance that we will be able to locate suitable acquisition candidates, acquire possible acquisition candidates, acquire such candidates on commercially reasonable terms, or integrate acquired businesses successfully in the future. In addition, any governmental

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review or investigation of our proposed acquisitions, such as by the Federal Trade Commission, may impede, limit or prevent us from proceeding with an acquisition. Future acquisitions may require us to incur additional debt and contingent liabilities, which may adversely affect our business, results of operations and financial condition. The process of integrating acquired businesses into our existing operations may result in operating, contract and supply chain difficulties, such as the failure to retain customers or management personnel. Such difficulties may divert significant financial, operational and managerial resources from our existing operations and make it more difficult to achieve our operating and strategic objectives.

Risks Relating To Our Common Stock

The price and trading volume of our common stock may experience extreme fluctuations and you could lose some or all of your investment.

Because we operate within the medical device segment of the healthcare industry, our stock price is likely to be volatile. The market price of our common stock may have and has had a history of substantial fluctuation due to a variety of factors, including, but not limited to:

These factors, some of which are not within our control, may cause the price of our stock to fluctuate substantially. If our quarterly or annual operating results fail to meet or exceed the expectations of securities analysts or investors, our stock price could drop suddenly and significantly. We believe the quarterly and annual comparisons of our financial results are not necessarily meaningful and should not be relied upon as an indication of our future performance.

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The market prices of the securities of medical device companies, particularly companies like ours without consistent product revenue and earnings, have been highly volatile and are likely to remain highly volatile in the future. This volatility has often been unrelated to the operating performance of particular companies. These market prices generally are not sustainable and are highly volatile. In the past, companies that experience volatility in the market price of their securities have often faced securities class action litigation. Whether or not meritorious, litigation brought against us could result in substantial costs, divert our management’s attention and resources and harm our ability to grow our business.

Sales of common stock by us in a capital raising transaction may dilute your ownership of common stock and cause a decline in the market price of our common stock.

We may need to raise capital in the future to fund our operations or new initiatives. If we raise funds by issuing equity securities, our stock price may decline and our existing shareholders may experience significant dilution. Furthermore, we may enter into financing transactions at prices that represent a substantial discount to market price. A negative reaction by investors and securities analysts to any sale of our equity securities could result in a decline in the trading price of our common stock. In January 2013 we raised funds through a public offering of 4.0 million shares of common stock. In December 2013 we issued 2.1 million shares of common stock in order to finance the acquisition of Estech. In February 2014 we raised funds through a public offering of 3.7 million shares of common stock.

Anti-takeover provisions in our amended and restated certificate of incorporation and amended and restated bylaws and under Delaware law could inhibit a change in control or a change in management that you consider favorable.

Provisions in our certificate of incorporation and bylaws could delay or prevent a change of control or change in management that would provide you with a premium to the market price of your common stock. These provisions include those:

In addition, Section 203 of the Delaware General Corporation Law limits business combination transactions with 15% stockholders that have not been approved by our board of directors. These provisions and others could make it difficult for a third party to acquire us, or for members of our board of directors to be replaced, even if doing so would be beneficial to our stockholders. Because our board of directors is responsible for appointing the members of our management team, these provisions could, in turn, affect any attempt to replace the current management team. If a change of control or change in management is delayed or prevented, you may lose an opportunity to realize a premium on your shares of common stock or the market price of our common stock could decline.

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We do not expect to pay dividends in the foreseeable future. As a result, you must rely on stock appreciation for any return on your investment.

We do not anticipate paying cash dividends on our common stock in the foreseeable future. Any payment of cash dividends will also depend on our financial condition, results of operations, capital requirements and other factors and will be at the discretion of our board of directors. Accordingly, you will have to rely on capital appreciation, if any, to earn a return on your investment in our common stock. Furthermore, pursuant to our credit facility, we are currently subject to restrictions on our ability to pay dividends and we may in the future become subject to other contractual restrictions on, or prohibitions against, the payment of dividends.

The requirements of being a public company may strain our resources and distract management.

As a public company, we are subject to the reporting requirements of the Securities Exchange Act of 1934, as amended (Exchange Act), and the Sarbanes-Oxley Act of 2002 (Sarbanes-Oxley Act). We are also subject to certain provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (Dodd-Frank Act). These requirements may place a strain on our systems and resources. The Exchange Act requires that we file annual, quarterly and current reports with respect to our business and financial condition. The Sarbanes-Oxley Act requires that we maintain effective disclosure controls and procedures and internal controls over financial reporting. In order to maintain and improve the effectiveness of our disclosure controls and procedures and internal control over financial reporting, significant resources and management oversight is required. While the Dodd-Frank Act requires the SEC to adopt certain rules and regulations relating to our public disclosures, corporate governance and executive compensation, among other things, we expect such rules and regulations will require significant attention from management. Compliance with all of these laws, rules and regulations may divert management’s attention from other business concerns, which could have a material adverse effect on our business, financial condition, results of operations and cash flows.

The SEC has adopted rules regarding the disclosure of the use of conflict minerals (commonly referred to as tantalum, tin, tungsten and gold) which are mined from the Democratic Republic of the Congo (DRC) and neighboring countries. Under the rules, we are required to disclose the procedures we employ to determine the sourcing of such minerals and metals produced from those minerals. The requirements require due diligence efforts and could affect the sourcing of components used in our products. If the conflict minerals included in our products are found to be sourced from the DRC or surrounding countries, we may take actions to change materials or product designs to reduce the possibility that our purchase of conflict minerals may fund armed groups in the region. These actions could add engineering and other costs to the manufacture of our products. We expect to incur costs in the investigation of the origin of the conflict minerals used in our products and in the reporting of the findings of our investigation. Our reputation may suffer if we have included conflict minerals in our products that are found to have funded armed groups in the DRC region.

None.

The Company maintains its headquarters in West Chester, Ohio in three leased facilities totaling approximately 55,600 square feet. The facilities contain the Company’s administrative, regulatory, engineering and product development, manufacturing and distribution functions. The monthly rent for this space is approximately $46. All West Chester leases will expire in August 2015. The Company maintains office space in San Ramon, California, which was the corporate headquarters for Estech. This office is approximately 3,800 square feet with monthly rent of approximately $7, and the lease will expire in December 2019. Additionally, the Company maintains office space in Minneapolis, Minnesota. This office is approximately 5,300 square feet with monthly rent of approximately $6, and the lease will expire in September 2021. Internationally, the Company maintains office space in the Netherlands. The monthly rent for this space is approximately $16, and the lease will expire in July 2015.

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The Company entered into a fifteen-year new building lease in 2014 in order to relocate its headquarters and West Chester, Ohio facilities from their current location to a 92,000 square foot building being constructed in Mason, Ohio and to be occupied exclusively by the Company. The initial monthly rent for the building will be approximately $113 and is subject to a two percent increase each year during the lease’s term.

The Company believes that its existing facilities are adequate to meet its immediate needs and that suitable additional space will be available in the future on commercially reasonable terms as needed.

The Company is not party to any material pending or threatened litigation. We may from time to time become a party to additional legal proceedings. See Note 11—Commitments and Contingencies to our Consolidated Financial Statements.

Not applicable.

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PART II

Common Stock Market Price

Our common stock is traded on the NASDAQ Global Market under the symbol “ATRC.” The following table sets forth the high and low closing sales price of our common stock for 2014 and 2013:

As of February 20, 2015, the closing price of our common stock on the NASDAQ Global Market was $18.50 per share, and the number of stockholders of record was 85.

Dividend Policy

The Company has not declared or paid any dividends on its capital stock since incorporation. Furthermore, pursuant to the credit facility, the Company is subject to certain restrictions on its ability to pay dividends. The Company currently expects to retain future earnings, if any, for use in the operation and expansion of the business and does not anticipate paying any cash dividends in the foreseeable future.

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Performance Graph

The following graph compares the cumulative total stockholder return on our common stock with the cumulative total return of the NASDAQ Composite and the NASDAQ Medical Equipment Index for the period beginning on January 1, 2009 and ending on December 31, 2014.

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The following table reflects selected financial data derived from our Consolidated Financial Statements for each of the last five years. The statement of operations data for the years ended December 31, 2014, 2013 and 2012 and the balance sheet data as of December 31, 2014 and 2013 are derived from our audited financial statements included in this Form 10-K. The statement of operations data for the years ended December 31, 2011 and 2010 and the balance sheet data as of December 31, 2012, 2011 and 2010 are derived from our audited financial statements not included in this Form 10-K. Historical results are not necessarily indicative of future results. The selected financial data set forth below should be read in conjunction with our financial statements, the related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included elsewhere in this Form 10-K.

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(Dollar amounts referenced in this Item 7 are in thousands, except per share amounts.)

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with the accompanying consolidated financial statements and notes thereto contained in Item 8, “Financial Statements and Supplementary Data,” to provide an understanding of our results of operations, financial condition and cash flows. This discussion and analysis contains forward-looking statements that involve risks, uncertainties and assumptions. The actual results may differ from those anticipated in these forward-looking statements as a result of many factors, including but not limited to those set forth under Item 1A “Risk Factors,” the cautionary statement regarding forward-looking statements at the beginning of Part I and elsewhere in this Form 10-K.

Overview

We are a medical device company providing innovative solutions designed to produce superior outcomes that reduce the economic and social burden of atrial fibrillation (Afib). Our Isolator Synergy^™ Ablation System is the only medical device approved by FDA for the treatment of Persistent and Longstanding Persistent forms of Afib. Our AtriClip Left Atrial Appendage (LAA) exclusion device is the most widely used LAA exclusion device worldwide. We have two ablation product lines. Our primary ablation product line, which accounts for a majority of our revenue, is the Isolator Synergy System, a bipolar radio frequency (RF) ablation generator and associated single use devices. We also offer a cryosurgery product line, including both reusable and single use cryoablation devices. Our AtriClip^™ Left Atrial Appendage Exclusion System (AtriClip system) is the most widely implanted LAA management device worldwide. We believe cardiothoracic surgeons are adopting our ablation and LAAM devices for the treatment of Afib and prevention of stroke.

Cardiothoracic surgeons have adopted our RF ablation and cryosurgery systems to treat an estimated 170,000 patients since 2004, and we believe that we are currently the market leader in the surgical treatment of Afib. Our products are utilized by cardiothoracic surgeons during both open-heart and minimally invasive surgical procedures, and in both concomitant and sole-therapy cases. During a concomitant open procedure, the surgeon ablates cardiac tissue and/or excludes the left atrial appendage, secondary, or concomitant, to a primary cardiac procedure such as a valve replacement or coronary bypass graft. Our Isolator Synergy System, which includes our Isolator Synergy clamps, an RF generator and related switchbox, is approved by FDA for the treatment of patients with persistent and long-standing persistent Afib during open-heart concomitant coronary artery bypass grafting and/or valve replacement or repair procedures. To date, none of our other products have been approved or cleared by FDA specifically for the treatment of Afib. Additionally, FDA has not determined that our products are safe and effective for preventing stroke. We anticipate that substantially all of our revenue for the foreseeable future will relate to products we currently sell, or are in the process of developing, which surgeons generally use to ablate cardiac tissue, to exclude the left atrial appendage, or to perform mitral and aortic valve replacement and repair.

We sell our products to medical centers in the U.S. through our direct sales force. AtriCure Europe, B.V., our wholly-owned subsidiary incorporated and based in the Netherlands, markets and sells our products throughout Europe and the Middle East primarily through distributors, while in certain markets, such as Germany, France, the United Kingdom and the Benelux region, we sell directly to medical centers. We also sell our products to other international distributors, primarily in Asia, South America and Canada. Our business is primarily transacted in U.S. dollars with the exception of transactions with our European subsidiary which are substantially transacted in Euros or British Pounds.

The December 2011 FDA approval of our Isolator Synergy System included the requirement to implement a 350-patient post-approval study (PAS). The PAS was designed to evaluate the long-term safety and efficacy of our Isolator Synergy System in the treatment of persistent and long-standing persistent Afib in patients

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undergoing open-heart procedures. We submitted a protocol for the PAS to the FDA in February 2012, and it was approved in September 2012. We submitted a protocol amendment to increase enrollment by up to 40 patients to the FDA in April 2014. The amendment was approved in June 2014. Enrollment in the trial was completed in October 2014 with 365 patients at 40 medical centers. We expect to release preliminary data from the study in early 2016, with a complete report expected to be published in 2017.

We conducted the Dual Epicardial Endocardial Persistent Atrial Fibrillation (DEEP AF) Feasibility clinical trial to evaluate use of the Isolator Synergy System for the treatment of Afib in a two-part procedure where a minimally invasive surgical ablation procedure is performed first, and an intracardiac catheter mapping and ablation procedure is then performed on a different day during the same hospitalization. The Staged DEEP AF Feasibility trial protocol was submitted to FDA in February 2012, and FDA approval to conduct the trial was received in June 2012. Enrollment in the Staged DEEP trial began during the third quarter of 2012 and was completed during the fourth quarter of 2013, with 30 patients enrolled at six medical centers.

We submitted an Investigational Device Exemption (IDE) application for the Staged DEEP pivotal trial to FDA in May 2014. The Staged DEEP pivotal trial evaluates the safety and efficacy of the Isolator Synergy System when used in a staged approach, where a minimally invasive surgical ablation procedure is first performed and the patient undergoes the intracardiac catheter procedure is performed approximately 90-120 days later. FDA conditional approval was received in July 2014. FDA full approval was received in September 2014. We have approval to enroll up to 220 subjects at 23 domestic medical centers and two international medical centers.

We are also conducting a Stroke Feasibility clinical trial with the AtriClip System. The Stroke Feasibility trial protocol was initially approved by the FDA in December 2011. An amendment to the protocol was submitted to the FDA and approved in October 2013. The trial evaluates the safety and efficacy of the AtriClip System for stroke prophylaxis (prevention of stroke) in patients with non-valvular Afib in whom long term oral anticoagulation therapy is medically contraindicated. We have approval to enroll up to 30 patients at seven medical centers during the course of the trial. Enrollment began in the first quarter of 2014 and currently stands at eleven patients.

In September 2014 we announced the release of the AtriClip FLEX™ device, with a more flexible aluminum shaft that allows surgeons to better adapt the applier to a patient’s particular anatomy. The device is one of four products within the AtriClip system portfolio. The AtriClip portfolio also includes the AtriClip PRO™, AtriClip long, and AtriClip standard, which have different lengths and deployment features. All AtriClip devices are 510(k) cleared by the FDA with an indication for the occlusion of the left atrial appendage under direct visualization in conjunction with other open cardiac surgical procedures.

During the fourth quarter of 2014 we released our CRYO3 probe. The CRYO3 device has an enhanced 10cm malleable aluminum probe, a retractable handle that exposes active probe length, a flexible tube set which allows for tight bending radius and an ergonomic handle that accommodates multiple hand positions.

In 2014 we also received 510(k) clearance from FDA for an expanded indication for our cryoICE cryosurgery probe. The expanded indication includes use of the CRYO2 probe to temporarily block pain by ablating peripheral nerves.

On December 31, 2013 we acquired Endoscopic Technologies, Inc. (Estech) by issuing 2,126,343 shares of common stock to shareholders of Estech as consideration and up to $26,000 in additional consideration based on the achievement of certain performance based milestones. The product portfolio acquired includes innovative surgical ablation devices that enable physicians to perform a variety of open concomitant and minimally invasive procedures using Estech’s proprietary temperature-controlled RF energy.

Our financial position was strengthened by our public offering of 3,996,250 shares of common stock in January 2013, which generated net proceeds of $26,872. We further strengthened our financial position through a

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public offering of 3,660,525 shares of common stock in February 2014, which generated net proceeds of $65,830. We believe our current financial position will support the execution of our strategic plan.

Results of Operations

Year Ended December 31, 2014 compared to December 31, 2013

The following table sets forth, for the periods indicated, our results of operations expressed as dollar amounts and as percentages of total revenue:

Revenue. Total revenue increased 31.2% (31.4% on a constant currency basis), from $81,889 in 2013 to $107,454 in 2014. Constant currency basis amounts are calculated by applying previous period foreign currency exchange rates to each of the comparable periods. Revenue from sales to customers in the United States increased $17,892, or 28.7%, and revenue from sales to international customers increased $7,673, or 39.2% (39.8% on a constant currency basis). The increase in sales to customers in the United States was primarily due to increased sales of ablation-related open-heart products of $6,819 and increased sales of the AtriClip system of $5,855. The increase in international revenue was primarily due to an increase in sales in Europe and Asia, across all product lines. Revenue from both the United States and Europe was positively impacted by the addition of products from the Estech acquisition.

Cost of revenue and gross margin. Cost of revenue increased $9,378, from $22,326 in 2013 to $31,704 in 2014. As a percentage of revenue, cost of revenue increased from 27.3% for the year ended December 31, 2013 to 29.5% for the year ended December 31, 2014. Gross margin for 2014 and 2013 was 70.5% and 72.7%, respectively. The decrease in gross margin was primarily due to an increased mix of international sales, which carry lower gross margins, an increase in costs related to the acquired Estech products, an increase in nonrecurring expense of approximately $344 associated with the transition of the Estech business and increased capital equipment placement.

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Research and development expenses. Research and development expenses increased $5,160, from $13,440 in 2013 to $18,600 in 2014. Approximately $559 of the increase was due to nonrecurring expenses related to the transition of the Estech business. The remaining increase in expense was primarily due to a $3,870 increase in product development, regulatory, clinical and quality personnel expense, a $1,306 increase in clinical trial spending and a $1,201 increase in intangible asset amortization offset by a $2,496 decrease in clinical affairs consulting.

Selling, general and administrative expenses. Selling, general and administrative expenses increased $16,496, or 28.9%, from $57,014 in 2013 to $73,510 in 2014. Approximately $3,207 of the increase was due to nonrecurring transaction, transition and severance expense related to the acquisition of Estech. An offset to selling, general and administrative expense of $8,032 was recognized due to the fair value adjustment of the Estech contingent consideration. The remaining increase was primarily due to an $11,652 increase in sales, marketing, training and administrative headcount and an increase in sales, marketing and training expenditures.

Net interest expense. Net interest expense was $209 for 2014 and $550 for 2013. Net interest expense primarily represents interest expense related to amounts outstanding on our term loan, amortization of debt issuance costs and expense related to the payoff of our term loan.

Other income and expense. Other income and expense consists primarily of foreign currency transaction gains and losses, grant income and non-employee option gains and losses related to the fair market value change for fully vested options outstanding for consultants, which are accounted for as free-standing derivatives. Net other income (expense) for 2014 and 2013 totaled $391 and ($3), respectively.

Year Ended December 31, 2013 compared to December 31, 2012

The following table sets forth, for the periods indicated, our results of operations expressed as dollar amounts and as percentages of total revenue:

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Revenue. Total revenue increased 16.6% (16.1% on a constant currency basis), from $70,247 in 2012 to $81,889 in 2013. Constant currency basis amounts are calculated by applying previous period foreign currency exchange rates to each of the comparable periods. Revenue from sales to customers in the United States increased $9,695, or 18.4%, and revenue from sales to international customers increased $1,947, or 11.0% (9.1% on a constant currency basis). The increase in sales to customers in the United States was primarily due to increased sales of ablation-related open-heart products of $4,963 and increased sales of the AtriClip system of $3,817. The increase in international revenue was primarily due to an increase in sales in Europe and Asia.

Cost of revenue and gross margin. Cost of revenue increased $2,093, from $20,233 in 2012 to $22,326 in 2013. As a percentage of revenue, cost of revenue decreased from 28.8% for the year ended December 31, 2012 to 27.3% for the year ended December 31, 2013. Gross margin for 2013 and 2012 was 72.7% and 71.2%, respectively. The increase in gross margin was primarily due to volume-driven leverage of manufacturing overhead expenses, a higher mix of domestic sales, lower sales of capital equipment and the strong performance of our AtriClip Pro product which was launched during the end of 2012.

Research and development expenses. Research and development expenses increased $1,293, from $12,147 in 2012 to $13,440 in 2013. The increase in expense was primarily due to a $661 increase in product development project expense, a $1,344 increase in product development, clinical and regulatory personnel expense and a $927 increase in clinical trial spending, offset by a $1,493 decrease in clinical affairs consulting.

Selling, general and administrative expenses. Selling, general and administrative expenses increased $11,949, or 26.5%, from $45,065 in 2012 to $57,014 in 2013. The increase was primarily due to an increase in sales and marketing expenditures and an increase in training related to FDA approval of our Isolator Synergy System for the treatment of Afib, along with $1,207 in expenses related to the acquisition of Estech, offset by a decrease in expense related to the departure of the Company’s Chief Financial Officer and Chief Executive Officer. Transaction, transition and severance expense totaling approximately $3,500 is expected in 2014 related to the acquisition of Estech.

Net interest expense. Net interest expense was $550 for 2013 and $791 for 2012. Net interest expense primarily represents interest expense related to amounts outstanding on our term loan and amortization of debt issuance costs. The interest rate on our term loan was 4.75% as of December 31, 2013 and 6.75% as of December 31, 2012.

Other income and expense. Other income and expense consists primarily of foreign currency transaction gains and losses, grant income and non-employee option gains and losses related to the fair market value change for fully vested options outstanding for consultants, which are accounted for as free-standing derivatives. Net other (expense) income for 2013 and 2012 totaled ($3) and $505, respectively.

Liquidity and Capital Resources

As of December 31, 2014 we had cash, cash equivalents and investments of $68,543 and short-term and long-term debt of $0, resulting in a net cash position of $68,543. We had unused borrowing capacity of approximately $12,383 under our revolving credit facility. Most of our cash is held by United States financial institutions. We had net working capital of $67,865 and an accumulated deficit of $138,424 as of December 31, 2014.

Cash flows used in operating activities. Net cash used in operating activities was $21,600 during 2014. The primary net uses of cash for operating activities were as follows:

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Cash flows used in investing activities. Net cash used in investing activities was $30,623 during 2014. The primary uses of cash for investing activities were $41,107 for purchases of available-for-sale securities and $9,207 related to the purchase of equipment, which included the placement of our RF and cryo generators with our customers. The uses of cash were partially offset by sources of cash from investing activities of $19,614 in maturities and sales of available-for-sale securities.

Cash flows provided by financing activities. Net cash provided by financing activities during 2014 was $65,871, which was primarily due to proceeds from the sale of stock of $65,830, proceeds from a construction financing obligation of $3,699, proceeds from stock option exercises of $1,916 and proceeds from the issuance of common stock under the employee stock purchase plan of $1,320, partially offset by debt and capital lease payments of $6,382, shares repurchased for payment of taxes on stock awards of $331 and $181 for payments of debt fees and the premium on the retirement of debt.

Credit facility. Our Loan and Security Agreement with Silicon Valley Bank (SVB), as amended, restated, and modified (Agreement) provides for a revolving credit facility under which we may borrow a maximum of $15,000. Borrowing availability under the revolving credit facility is based on the lesser of $15,000 or a borrowing base calculation as defined by the Agreement. As of December 31, 2014 we had no borrowings under the revolving credit facility, and we had borrowing availability of $12,383. The applicable borrowing rate on the revolving facility is the prime rate during a period when we meet the requirements for Streamline Period, which are based on available cash and amounts drawn under the credit facility, and prime plus 1.25% at all other times. The revolving credit facility expires on April 30, 2016. The Company repaid the term loan portion of the credit facility in full in March 2014, resulting in $0 outstanding under the term loan as of December 31, 2014.

The Agreement contains covenants that include, among others, covenants that limit our ability to dispose of assets, enter into mergers or acquisitions, incur indebtedness, incur liens, pay dividends or make distributions on our capital stock, make investments or loans, and enter into certain affiliate transactions, in each case subject to customary exceptions for a credit facility of this size and type. Additional covenants apply when we have outstanding borrowings under the revolving credit facility or when we hold less than $20,000 in cash and investments with SVB. Financial covenants under the credit facility include a minimum EBITDA and a minimum liquidity ratio. Further, a minimum fixed charge ratio applies when we achieve specific covenant milestones. None of the covenants must be applied as of December 31, 2014. The occurrence of an event of default could result in an increase to the applicable interest rate by 3.0%, an acceleration of all obligations under the Agreement, an obligation to repay all obligations in full and a right by SVB to exercise all remedies available to it under the Agreement and related agreements including the Guaranty and Security Agreement. Specified assets have been pledged as collateral.

We have an outstanding letter of credit of €75 issued to our European subsidiary’s corporate credit card provider which will expire on June 30, 2015.

Uses of liquidity and capital resources. Our future capital requirements depend on a number of factors, including the rate of market acceptance of our current and future products, the resources we devote to developing and supporting our products, future expenses to expand and support our sales and marketing efforts, costs

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relating to changes in regulatory policies or laws that affect our operations and costs of filing, costs associated with clinical trials and securing regulatory approval for new products, costs associated with integrating acquired businesses, costs associated with prosecuting, defending and enforcing our intellectual property rights and possible acquisitions and joint ventures. Global economic turmoil may adversely impact our revenue, access to the capital markets or future demand for our products.

In July 2011 we filed a shelf registration statement with the SEC which allows us to sell any combination of senior or subordinated debt securities, common stock, preferred stock, warrants, depositary shares and units in one or more offerings should we choose to do so in the future. In January 2013 we sold approximately 3,996,250 shares of common stock under the shelf registration which resulted in net proceeds of approximately $26,872. The unissued and unsold securities remaining on this registration statement were removed and withdrawn from registration in February 2014.

In January 2014 we filed a shelf registration statement with the SEC which allows us to sell any combination of senior or subordinated debt securities, common stock, preferred stock, warrants, depositary shares and units in one or more offerings should we choose to do so in the future. In February 2014 we sold 3,660,525 shares of common stock under the shelf registration which resulted in net proceeds of approximately $65,830.

We believe that our current cash, cash equivalents and investments, along with the cash we expect to generate or use for operations or access via our revolving credit facility, will be sufficient to meet our anticipated cash needs for working capital and capital expenditures for at least the next twelve months. If our sources of cash are insufficient to satisfy our liquidity requirements, we may seek to sell additional equity or debt securities or obtain a revised or additional credit facility. The sale of additional equity or convertible debt securities could result in dilution to our stockholders. If additional funds are raised through the issuance of debt securities, these securities could have rights senior to those associated with our common stock and could contain covenants that would restrict our operations. Additional financing may not be available at all, or in amounts or terms acceptable to us. Finally, our credit facilities require compliance with certain financial and other covenants. If we are unable to obtain this additional financing, we may be required to reduce the scope of our planned research and development, clinical activities and selling and marketing efforts.

Contractual Obligations and Commitments

The following table sets forth our approximate aggregate obligations at December 31, 2014 for future payments under contracts and other contingent commitments:

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Off-Balance-Sheet Arrangements

As of December 31, 2014 we had operating lease agreements that were not recorded on the Consolidated Balance Sheets. Operating leases are utilized in the normal course of business.

Inflation

Inflation has not had a significant impact on our historical operations and we do not expect it to have a significant impact on our results of operations or financial condition in the foreseeable future.

Critical Accounting Policies and Estimates

Our discussion and analysis of our financial condition and results of operations is based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets and liabilities, revenue and expenses, and disclosures of contingent assets and liabilities at the date of the financial statements. On a periodic basis, we evaluate our estimates, including those related to sales returns and allowances, accounts receivable, inventories and share-based compensation. We use authoritative pronouncements, historical experience and other assumptions as the basis for making estimates. Actual results could differ from those estimates under different assumptions or conditions.

We believe the following critical accounting policies affect our more significant judgments and estimates used in the preparation of our consolidated financial statements.

Revenue Recognition—Revenue is generated primarily from the sale of our disposable surgical devices. Pursuant to our standard terms of sale, revenue is recognized when title to the goods and risk of loss transfers to customers and there are no remaining obligations that will affect customers’ final acceptance of the sale. Generally, our standard terms of sale define the transfer of title and risk of loss to occur upon shipment to the respective customer. We generally do not maintain any post-shipping obligations to the recipients of the products. No installation, calibration or testing of this equipment is performed by AtriCure subsequent to shipment to the customer in order to render it operational. Cost of freight for shipments made to customers is included in cost of revenue. Sales and other value-added taxes collected from customers and remitted to governmental authorities are excluded from revenue. We sell our products primarily through a direct sales force and through a wholly-owned subsidiary, AtriCure Europe B.V. Terms of sale are generally consistent for both end-users and distributors except that payment terms are generally net 30 days for end-users and net 60 days for distributors.

We account for revenue in accordance with FASB ASC 605, “Revenue Recognition” (ASC 605). We determine the timing of revenue recognition based upon factors such as passage of title, installation, payment terms and ability to return products. We recognize revenue when all of the following criteria are met: (i) there is persuasive evidence that an arrangement exists; (ii) delivery of the products and/or services has occurred; (iii) the selling price is fixed or determinable; and (iv) collectability is reasonably assured.

Allowance for Uncollectible Accounts Receivable—We evaluate the collectability of accounts receivable in order to determine the appropriate reserve for doubtful accounts. In determining the amount of the reserve, we consider the aging of account balances, historical credit losses, customer-specific information and other relevant

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factors. We periodically review accounts receivable and adjust the allowance based on current circumstances and charge off uncollectible receivables against the allowance when all attempts to collect the receivable have failed. Our history of write-offs against the allowance has not been significant.

Inventories—Our inventories are stated at the lower of cost or market using approximate costs based on the first-in, first-out cost method (FIFO) and consist of raw materials, work in process and finished goods. We estimate and record our inventory reserve quarterly based on product usage for excess, slow moving and obsolete inventory as well as for inventory with a carrying value in excess of its net realizable value. Our industry is characterized by rapid product development and frequent new product introductions. Uncertain timing of product approvals, variability in product launch strategies and variation in product utilization all impact excess and obsolete inventory.

Property and Equipment—We state property and equipment at cost less accumulated depreciation. Depreciation is computed using the straight-line method for financial reporting purposes and applied over the estimated useful lives of the assets. Included in property and equipment are generators and other capital equipment (such as our switchbox units and cryosurgical consoles) that are loaned at no cost to direct customers that use our disposable products. These generators are depreciated over a period of one to three years, which approximates their useful lives, and such depreciation is included in cost of revenue. We estimate the useful lives of this equipment based on anticipated usage by our customers and the timing and impact of our expected new technology rollouts. To the extent we experience changes in the usage of this equipment or the introductions of new technologies, the estimated useful lives of this equipment may change in a future period.

Intangible Assets—Intangible assets with a definite life are amortized on a straight-line basis, as appropriate, with estimated useful lives ranging from one to ten years, and are tested for impairment whenever events or changes in circumstances indicate that the carrying amount of an intangible asset may not be recoverable.

Goodwill—Goodwill represents the excess of purchase price over the fair value of the net assets acquired in business combinations. We test goodwill for impairment annually during the fourth quarter, or more often if impairment indicators are present. The Company uses readily available market information and income valuation approaches to estimate the fair value of the reporting unit. The income valuation approach is developed using the Company’s best estimates based on reasonable and supportable assumptions and projections.

Share-Based Employee Compensation—We account for share-based compensation for all employee share-based payment awards, including stock options, restricted stock, performance shares and stock purchases related to an employee stock purchase plan, based on their estimated fair values. We estimate the fair value of options on the date of grant using the Black-Scholes option pricing model (Black-Scholes model). Our determination of fair value of share-based payment awards is affected by our stock price, as well as assumptions regarding a number of highly complex and subjective variables. These variables include but are not limited to our expected stock price volatility over the term of the awards and actual and projected employee stock option exercise behaviors. For non-employee options, the fair value at the date of grant is subject to adjustment at each vesting date based upon the fair value of our common stock. The fair value of our market-based performance option grants is estimated at the date of grant using a Monte-Carlo simulation. The value of the portion of the award that is ultimately expected to vest is recognized as expense over the requisite service periods in our Consolidated Statement of Operations. The expense has been reduced for estimated forfeitures.

We estimate the fair value of restricted stock awards based upon the grant date closing market price of our common stock. Our determination of fair value is affected by our stock price as well as assumptions regarding the number of shares expected to vest.

We also have an employee stock purchase plan (ESPP or Plan) which is available to all eligible employees as defined by the Plan. Under the ESPP, shares of our common stock may be purchased at a discount. We

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estimate the number of shares to be purchased under the Plan and record compensation expense based upon the fair value of the stock at the beginning of the purchase period calculated using the Black-Scholes model is recognized over each purchase period.

We have historically issued stock options to non-employee consultants as a form of compensation for services provided to us. Because the options require settlement by our delivery of registered shares and because the tax withholding provisions in the awards allow the options to be partially net-cash settled, these options, when vested, are no longer eligible for equity classification and are, thus, subsequently accounted for as derivative liabilities under FASB ASC 815, “Derivatives and Hedging” (ASC 815), until the awards are ultimately either exercised or forfeited. Accordingly, the vested non-employee options are classified as liabilities, and their fair value is remeasured using the Black-Scholes model at each reporting period.

Taxes—Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rates is recognized in the period that includes the enactment date.

Our estimate of the valuation allowance for deferred tax assets requires us to make significant estimates and judgments about its future operating results. Deferred tax assets are reduced by valuation allowances if, based on the consideration of all available evidence, it is more-likely-than-not that some portion of the deferred tax asset will not be realized. Significant weight is given to evidence that can be objectively verified. We evaluate deferred tax assets on a quarterly basis to determine if valuation allowances are required by considering all available evidence. Deferred tax assets are realized by having sufficient future taxable income to allow the related tax benefits to reduce taxes otherwise payable. The sources of taxable income that may be available to realize the benefit of deferred tax assets are future reversals of existing taxable temporary differences, future taxable income, exclusive of reversing temporary differences and carryforwards, taxable income in carry-back years and tax planning strategies that are both prudent and feasible. In evaluating whether to record a valuation allowance, the applicable accounting standards deem that the existence of cumulative losses in recent years is a significant piece of objectively verifiable negative evidence that must be overcome by objectively verifiable positive evidence to avoid the need to record a valuation allowance. We have recorded a full valuation allowance against its net deferred tax assets as it is more likely than not that the benefit of the deferred tax assets will not be recognized in future periods.

Our discussion and analysis of our financial condition and results of operations is based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets and liabilities, revenue and expenses and disclosures of contingent assets and liabilities at the date of the financial statements. On a periodic basis, we evaluate our estimates, including those related to sales returns and allowances, accounts receivable, inventories and share-based compensation. We use authoritative pronouncements, historical experience and other assumptions as the basis for making estimates. Actual results could differ from those estimates under different assumptions or conditions. We have described our significant accounting policies in Note 1 – Description of Business and Summary of Significant Accounting Policies to our consolidated financial statements included in this Form 10-K.

We believe our critical accounting policies regarding revenue recognition, allowance for uncollectible accounts receivable, inventories, property and equipment, intangible assets, goodwill, share-based employee compensation and taxes affect our more significant judgments and estimates used in the preparation of our consolidated financial statements. We base our judgments and estimates on historical experience, current conditions and other reasonable factors.

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Recent Accounting Pronouncements

In May 2014 the FASB issued a final standard on revenue from contracts with customers. The standard, issued as FASB ASU 2014-09, “Revenue from Contracts with Customers” (ASU 2014-09), outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. The ASU is effective for interim and annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. A full retrospective or modified retrospective approach may be taken to adopt the guidance in the ASU. The Company is currently evaluating the impact of the provisions of ASU 2014-09 on its consolidated financial position, results of operations and related disclosures.

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(Amounts referenced in this Item 7A are in thousands, except per share amounts.)

The Company has financial instruments accounted for as free-standing derivatives related to certain of the Company’s share-based payment arrangements that are outside the scope of FASB ASC 718 and are subject to FASB ASC 815, which requires fully vested stock options held by certain non-employee consultants to be accounted for as liability awards until these awards are exercised or forfeited. The fair value of these awards is remeasured at each reporting period until the awards are settled or expire. (Income) expense recorded based on the remeasurement of these options was approximately ($183), $272 and ($179) for 2014, 2013 and 2012, respectively. As of December 31, 2014, stock options to acquire 20 shares of common stock held by non-employee consultants remained unexercised, and a liability of $120 was included in accrued liabilities in the accompanying Consolidated Balance Sheet. The Company is exposed to the volatility of the market price of its stock.

The Company is exposed to various market risks, which include potential losses arising from adverse changes in market rates and prices, such as foreign exchange fluctuations and changes in interest rates. Interest on the revolving loan will accrue at the prime rate during a Streamline Period and prime plus 1.25% during a Non-Streamline Period (as defined in the Amended Agreement).

For the years ended December 31, 2014 and 2013, products sold by AtriCure Europe, B.V. accounted for 16.2% and 12.9%, respectively, of the Company’s total revenue. Since such revenue was primarily denominated in Euros, the Company is exposed to exchange rate fluctuations between the Euro and the U.S. Dollar. To date, the effect of the foreign exchange rate fluctuations on AtriCure’s financial results has not been significant. For the years ended December 31, 2014 and 2013, foreign currency transaction (losses) gains of ($523) and $269, respectively, were recorded primarily in connection with partial settlements of the intercompany receivable balance with the subsidiary. For revenue denominated in Euros, if there is an increase in the rate at which Euros are exchanged for U.S. Dollars, it will require more Euros to equal a specified amount of U.S. Dollars than before the rate increase. In such cases, and if products are priced in Euros, the Company will receive less in U.S. Dollars than was received before the rate increase went into effect. If products are priced in U.S. Dollars and competitors price their products in Euros, an increase in the relative strength of the U.S. Dollar could result in the Company’s price not being competitive in a market where business is transacted in Euros. The Euro to U.S. dollar conversion rate fluctuations may impact our reported revenue and expenses.

The Company currently invests its cash primarily in money market accounts, U.S. government agencies and securities, corporate bonds and commercial paper. Although the Company believes its cash to be invested in a conservative manner, with cash preservation being the primary investment objective, the value of the securities held will fluctuate with changes in the financial markets including, among other things, changes in interest rates, credit quality and general volatility. This risk is managed by investing in high quality investment grade securities with short-term maturities.

Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalent balances. Certain of AtriCure’s cash and cash equivalents balances exceed FDIC insured limits or are invested in money market accounts with investment banks that are not FDIC insured. The Company places its cash and cash equivalents in what it believes to be credit-worthy financial institutions. As of December 31, 2014 $28,457 of the cash and cash equivalents balance was in excess of the FDIC limits.

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ATRICURE, INC. AND SUBSIDIARIES

INDEX TO FINANCIAL STATEMENTS

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Directors and Stockholders of

AtriCure, Inc. and subsidiaries

West Chester, Ohio

We have audited the accompanying consolidated balance sheets of AtriCure, Inc. and subsidiaries (the “Company”) as of December 31, 2014 and 2013, and the related consolidated statements of operations and comprehensive loss, stockholders’ equity, and cash flows for each of the three years in the period ended December 31, 2014. Our audits also included the financial statement schedule listed in the Index at Item 15. These financial statements and financial statement schedule are the responsibility of the Company’s management. Our responsibility is to express an opinion on the financial statements and financial statement schedule based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, such consolidated financial statements present fairly, in all material respects, the financial position of AtriCure, Inc. and subsidiaries at December 31, 2014 and 2013, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2014, in conformity with accounting principles generally accepted in the United States of America. Also, in our opinion, such financial statement schedule, when considered in relation to the basic consolidated financial statements taken as a whole, presents fairly, in all material respects, the information set forth therein.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the Company’s internal control over financial reporting as of December 31, 2014, based on the criteria established in Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated March 2, 2015 expressed an unqualified opinion on the Company’s internal control over financial reporting.

/s/ Deloitte & Touche LLP

Cincinnati, Ohio

March 2, 2015

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ATRICURE, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

DECEMBER 31, 2014 and 2013

(In Thousands, Except Per Share Amounts)

See accompanying notes to consolidated financial statements.

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ATRICURE, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

YEARS ENDED DECEMBER 31, 2014, 2013 and 2012

(In Thousands, Except Per Share Amounts)