Dorman Products, Inc. - Annual Report: 2012 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 29, 2012

OR

For the transition period from                      to                     

Commission file number 0-18914

DORMAN PRODUCTS, INC.

(Exact name of registrant as specified in its charter)

3400 East Walnut Street, Colmar, Pennsylvania 18915

(Address of principal executive offices) (Zip Code)

(215) 997-1800

(Registrant’s telephone number, including area code)

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  x    No  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Securities 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 Web site, 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 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 the definitions 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

As of February 25, 2013 the registrant had 36,465,006 shares of common stock, $0.01 par value, outstanding. The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant as of June 30, 2012 was $540,916,389.

DOCUMENTS INCORPORATED BY REFERENCE

Certain portions of the registrant’s definitive proxy statement, in connection with its Annual Meeting of Shareholders, to be filed with the Securities and Exchange Commission within 120 days after December 29, 2012, are incorporated by reference into Part III of this annual report on Form 10-K.

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DORMAN PRODUCTS, INC.

INDEX TO ANNUAL REPORT ON FORM 10-K

DECEMBER 29, 2012

The Company’s fiscal year ends on the last Saturday of the calendar year.

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PART I

Item 1. Business.

General

Dorman Products, Inc. was incorporated in Pennsylvania in October 1978. As used herein, unless the context otherwise requires, “Dorman”, the “Company”, “we”, “us”, or “our” refers to Dorman Products, Inc. and its subsidiaries.

We are a supplier of automotive and heavy duty truck replacement parts and fasteners and service line products primarily for the automotive aftermarket. We market approximately 133,000 different stock keeping units (“SKU’s”) of automotive replacement parts (including brake parts), fasteners and service line products many of which we design and engineer. We believe we are the dominant aftermarket supplier of original equipment “dealer only” items. Original equipment dealer only parts are those which were traditionally available to consumers only from original equipment manufacturers or used parts from salvage yards and include, among other parts, intake manifolds, exhaust manifolds, oil cooler lines, window regulators, radiator fan assemblies, power steering pulleys, harmonic balancers, tire pressure monitor sensors, and keyless entry devices. Fasteners include such items as oil drain plugs, wheel bolts, and wheel lug nuts. Approximately 85% of our products are sold under our brand names and the remainder is sold for resale under customers’ private labels, other brands or in bulk. Our products are sold primarily in the United States through automotive aftermarket retailers (such as AutoZone, Advance Auto Parts, and O’Reilly Auto Parts), national, regional and local warehouse distributors (such as Carquest and NAPA) and specialty markets and salvage yards. We distribute automotive replacement parts internationally, with sales into Europe, Mexico, the Middle East, Asia and Canada.

The Automotive Aftermarket

The automotive replacement parts market is made up of two components: parts for passenger cars and light trucks, which accounted for projected industry sales of approximately $231 billion in 2012, and parts for medium and heavy duty trucks, which accounted for projected industry sales of approximately $77 billion in 2012¹. We market products primarily for passenger cars and light trucks, and, more recently, for medium and heavy duty trucks.

Two distinct groups of end-users buy replacement vehicle (automotive and truck) parts: (i) individual consumers, who purchase parts to perform “do-it-yourself” repairs on their own vehicles; and (ii) professional installers, which include vehicle repair shops and the dealership service departments. The individual consumer market is typically supplied through retailers and through the retail arms of warehouse distributors. Vehicle repair shops generally purchase parts through local independent parts wholesalers and through national parts distributors. Automobile dealership service departments generally obtain parts through the distribution systems of vehicle manufacturers and specialized national and regional parts distributors.

Spending in the light vehicle aftermarket can generally be grouped into three segments: discretionary, maintenance and repair. Discretionary, such as accessories and performance, tends to move in-line with consumer discretionary spending. Maintenance is composed of products and services, such as oil and oil changes, and tends to be less correlated with discretionary spending. The repair segment consists mainly of replacement parts which fail over time and tends to be less cyclical as it is largely comprised of parts necessary for a vehicle to function properly or safely. We believe the majority of our products fall into the repair segment.

The increasing complexity of automobiles and the number of different makes and models of automobiles have resulted in a significant increase in the number of products required to service the domestic and foreign automotive fleet. Accordingly, the number of parts required to be carried by retailers and wholesale distributors has increased substantially. The requirement to include more products in inventory and the significant consolidation among distributors of automotive replacement parts have in turn resulted in larger distributors.

Retailers and others who purchase aftermarket automotive repair and replacement parts for resale are constrained to a finite amount of space in which to display and stock products. Thus, the reputation for quality, customer service, and line profitability which a supplier enjoys are significant factors in a purchaser’s decision as to which product lines to carry in the limited space available. Further, because of the efficiencies achieved through the ability to order all or part of a complete line of products from one supplier (with possible volume discounts), as opposed to satisfying the same requirements through a variety of different sources, retailers and other purchasers of automotive parts seek to purchase products from fewer but stronger suppliers.

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Brands and Products

We sell approximately 133,000 different automotive replacement parts, fasteners and service line products to meet a variety of needs. Our DORMAN® NEW SINCE 1918™ marketing campaign positions our brands under a single corporate umbrella - DORMAN®. Our products are now sold under one of the nine DORMAN® sub-brands as follows:

We also generate revenues from the sale of parts that we package for ourselves, or others, for sale in bulk or under the private labels of parts manufacturers and national warehouse distributors (such as Carquest and NAPA).

We group our products into four major classes: power-train, automotive body, chassis, and hardware. The following table represents each of the four classes as a percentage of net sales for each of the last three fiscal years.

Our power-train product line includes intake and exhaust manifolds, cooling products, harmonic balancers, fluid lines, fluid reservoirs, connectors, 4 wheel drive components and axles, drain plugs, and other engine, transmission and axle components. Our line of automotive body products include door handles and hinges, window lift motors, window regulators, switches and handles, wiper components, lighting, electrical, and other interior and exterior automotive body components. Chassis products include brake hardware and hydraulics, wheel and axle hardware, suspension arms, knuckles, links, bushings, and other suspension, steering and brake components. Hardware products include threaded bolts, auto body and home fasteners, automotive and home electrical wiring components, and other hardware assortments and merchandise.

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Our HD Solutions™ brand of New to the Heavy Duty Aftermarket parts provides coverage for class 4-8 heavy vehicles in a variety of product lines including coolant tubes, door handles and other body parts, fluid reservoirs, headlights and lighting, hood components, window regulators, wiper transmissions, and many other parts. Our Heavy Duty Aftermarket parts feature re-engineered replacement parts aimed at increasing durability, complete kits that yield time and cost savings, and products that enable technicians to replace just the failed unit component part rather than an entire assembly.

In September 2011, our Board of Directors approved the exit from the international portion of our ScanTech business, which was headquartered outside of Stockholm, Sweden. ScanTech marketed and distributed a line of Volvo and Saab replacement parts throughout the world. As part of the exit, ScanTech’s North American business, which was serviced from Sweden, was transferred to our U.S. distribution centers, while ScanTech’s international business was liquidated.

We warrant our products against certain defects in material and workmanship when used as designed on the vehicle on which it was originally installed. We offer a limited lifetime warranty on all of our products. Our warranty limits the customer’s remedy to the repair or replacement of the part that is defective.

Product Development

Product development is central to our business. The development of a broad range of products, many of which are not conveniently or economically available elsewhere, has in part, enabled us to grow to our present size and is important to our future growth. In developing our products, our strategy has been to design and package parts so as to make them better and easier to install and/or use than the original parts they replace and to sell automotive parts for the broadest possible range of uses. Each new product idea is reviewed by our product management staff, as well as by members of the production, sales, finance, marketing, and administrative staffs.

Through careful evaluation, exacting design and precise tooling, we are frequently able to offer products which fit a broader range of makes and models than the original equipment parts they replace. One such innovation is our replacement intake manifold which fits not only a variety of Chevrolet, Ford and Chrysler models, but also a range of foreign makes and models. We also developed a window lift motor which fits not only a variety of General Motors models, but also Toyota, Mitsubishi and Suzuki vehicles. This flexibility assists retailers and other purchasers in maximizing the productivity of the limited space available for each class of part sold. Further, where possible, we improve our parts so they are better than the parts they replace. Thus, many of the our products are simpler to install or use, such as a replacement “split boot” for a constant velocity joint that can be installed without disassembling the joint itself and a replacement spare tire hold-down bolt that is longer and easier to thread than the original equipment bolt it replaced. In addition, we often package different items in complete kits to ease installation.

Ideas for expansion of our product lines arise through a variety of sources. We maintain an in-house product management staff that routinely generates ideas for new parts and the expansion of existing lines. Further, we maintain an “800” telephone number and an Internet site for “New Product Suggestions” and receive, either through our sales force or product development team, many ideas from our customers and end-users as to which types of presently unavailable parts the ultimate consumers are seeking.

Sales and Marketing

We market our products to three groups of purchasers who in turn supply individual consumers and professional installers. As of December 29, 2012:

(i) approximately 49% of our revenues were generated from sales to automotive aftermarket retailers (such as AutoZone, Advance Auto Parts, and O’Reilly Auto Parts), local independent parts wholesalers and national general merchandise chain retailers. We sell many of our products to virtually all major chains of automotive aftermarket retailers;

(ii) approximately 43% of our revenues were generated from sales to automotive parts distributors (such as Carquest and NAPA), which may be local, regional or national in scope, and which may also engage in retail sales; and

(iii) the balance of our revenues (approximately 8%) are generated from international sales and sales to special markets, which include, among others, mass merchants (such as Wal-Mart), salvage yards and the parts distribution systems of parts manufacturers.

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We use a number of different methods to sell our products. Our more than 50 person direct sales force and sales support staff solicits purchases of our products directly from customers, as well as manages the activities of approximately 20 independent manufacturers’ representative agencies worldwide. We use independent manufacturers’ representative agencies to help service existing automotive retail and automotive parts distribution customers, providing frequent on-site contact. We increase sales by securing new customers, by adding new product lines and expanding product selection within existing customers. For certain of our major customers, and our private label purchasers, we rely primarily upon the direct efforts of our sales force who, together with our marketing department and our executive officers, coordinate the more complex pricing and ordering requirements of these accounts.

Our sales efforts are not directed merely at selling individual products, but rather more broadly towards selling groups of related products that can be displayed on attractive Dorman-designed display systems, thereby maximizing each customer’s ability to present our product line within the confines of the available area.

We prepare a number of catalogs, application guides and training materials designed to describe our products and other applications as well as to train our customers’ sales teams in the promotion and sale of our products. A catalog of all of our parts is available on our website.

We currently service more than 2,800 active accounts. During fiscal 2012, fiscal 2011 and fiscal 2010, four customers (AutoZone, Advance Auto Parts, O’Reilly Auto Parts and Genuine Parts Co.) each accounted for more than 10% and in the aggregate accounted for 57% of net sales in each period.

Manufacturing

Substantially all of our products are manufactured by third parties. Because numerous manufacturers are available to manufacture our products, we are not dependent upon the services of any one manufacturer or any small group of them. No one manufacturer supplies more than 10% of our products. In fiscal 2012, as a percentage of our total dollar volume of purchases, approximately 20% of our products were purchased from various suppliers throughout the United States and the balance of our products were purchased directly from vendors in a variety of foreign countries.

Once a new product has been identified, our engineering department produces detailed proprietary engineering drawings and prototypes which are used to solicit bids for manufacture from a variety of vendors in the United States and abroad. After a vendor is selected, the vendor produces tooling which we then own. A pilot run of the product is produced and subjected to rigorous testing by our engineering department and, on occasion, by outside testing laboratories and facilities in order to evaluate the precision of manufacture and the resiliency and structural integrity of the materials used. If acceptable, the product then moves into full production.

Packaging, Inventory and Shipping

Finished products are received at one or more of our facilities, depending on the type of part. It is our practice to inspect samples of shipments based upon vendor performance. If cleared, these shipments of finished parts are logged into our computerized production tracking systems and staged for packaging, if necessary.

We employ a variety of custom-designed packaging machines which include blister sealing, skin film sealing, clamshell sealing, bagging and boxing lines. Packaged product contains our label (or a private label), a part number, a universal packaging bar code suitable for electronic scanning, a description of the part and, if appropriate, installation instructions. Products are also sold in bulk to automotive parts manufacturers and packagers. Computerized tracking systems, mechanical counting devices and experienced workers combine to assure that the proper variety and numbers of parts meet the correct packaging materials at the appropriate places and times to produce the required quantities of finished products.

Completed inventory is stocked in the warehouse portions of our facilities and is stored and organized to facilitate the most efficient methods of retrieving product to fill customer orders. We strive to maintain a level of inventory to adequately meet current customer order demand with additional inventory to satisfy new customer orders and special programs. We maintain a “safety stock” of inventory to compensate for fluctuations in demand and delivery.

We ship our products from all of our locations by contract carrier, common carrier or parcel service. Products are generally shipped to the customer’s main warehouses for redistribution within their network. In certain circumstances, at the request of the customer, we ship directly to the customer’s stores either via smaller direct ship orders or consolidated store orders that are cross docked.

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Competition

The replacement automotive parts industry is highly competitive. Various competitive factors affecting the automotive aftermarket are price, product quality, breadth of product line, range of applications and customer service. Substantially all of our products are subject to competition with similar products manufactured by other manufacturers of aftermarket automotive repair and replacement parts. Some of these competitors are divisions and subsidiaries of companies much larger than us, and possess a longer history of operations and greater financial and other resources than we do. Further, some of our private label customers also compete with us.

Proprietary Rights

While we take steps to register our trademarks when possible, we believe that our business is not heavily dependent on such trademark registration. Similarly, while we actively seek patent protection for the products and improvements which we develop, we do not believe that patent protection is critical to the success of our business. Rather, the quality, price and availability of our product is critical to our success.

Employees

At December 29, 2012, we had 1,321 employees worldwide, essentially all of which were employed full-time. Of these employees, 817 were engaged in production, inventory, and quality control, 254 were involved in engineering, product development and purchasing, 106 were employed in sales and customer service, and the remaining 144 were devoted to administration.

No domestic employees are covered by any collective bargaining agreement. We consider our relations with our employees to be generally good.

Available Information

Our Internet address is www.dormanproducts.com. The information on this website is not and should not be considered part of this Form 10-K and is not incorporated by reference in this Form 10-K. This website is, and is only intended to be, for reference purposes only. We make available free of charge on our web site our annual report on Form 10-K, quarterly reports on Form 10-Q and current reports on 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, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission (the “SEC”). In addition, we will provide, at no cost, paper or electronic copies of our reports and other filings made with the SEC. Requests should be directed to: Dorman Products, Inc. - Office of General Counsel, 3400 East Walnut Street, Colmar, Pennsylvania 18915.

Item 1A. Risk Factors

In addition to the other information set forth in this report, you should carefully consider the following factors, which could materially affect our business, financial condition or future results. The risks described below are not the only risks we face. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial also may materially affect our business, financial conditions or results of operations.

We May Lose Business to Competitors.

Competition within the automotive aftermarket parts business is intense. We compete in North America with both original equipment parts manufacturers and with companies that, like us, supply parts only to the automotive aftermarket. We expect such competition to continue. If we are unable to compete successfully in our industry we could lose customers.

Unfavorable Economic Conditions May Adversely Affect Our Business.

Adverse changes in economic conditions, including inflation, recession, or instability in the financial markets or credit markets may either lower demand for our products or increase our operational costs, or both. Such conditions may also materially impact our customers, suppliers and other parties with whom we do business. Our revenue will be adversely affected if demand for our products declines. The impact of unfavorable economic conditions may also impair the ability of our customers to pay for products they have purchased. As a result, reserves for doubtful accounts and write-offs of accounts receivables may increase and failure to collect a significant portion of amounts due on those receivables could have a material adverse effect on our results of operations and financial condition.

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The Loss or Decrease in Sales Among One of Our Top Customers Could Have a Substantial Negative Impact on Our Sales and Operating Results.

A significant percentage of our sales has been, and will continue to be, concentrated among a relatively small number of customers. During fiscal 2012, fiscal 2011 and fiscal 2010, four customers (AutoZone, Advance Auto Parts, O’Reilly Auto Parts and Genuine Parts Co.) each accounted for more than 10% and in the aggregate accounted for 57% of net sales in each period. We anticipate that this concentration of sales among customers will continue in the future. The loss of a significant customer or a substantial decrease in sales to such a customer could have a material adverse effect on our sales and operating results.

Customer Consolidation in the Automotive Aftermarket May Lead to Customer Contract Terms Less Favorable to Us Which May Negatively Impact Our Financial Results.

The automotive aftermarket has been consolidating over the past several years. As a result, many of our customers have grown larger and therefore have more leverage in the arms-length negotiations of agreements with us for the sale of our products. Customers may require us to provide extended payment terms and returns of slow moving product in order to obtain new or retain existing business. While we attempt to avoid or minimize such concessions, in some cases payment terms to customers have been extended and returns of product have exceeded historical levels. The product returns primarily affect our profit levels while payment terms extensions generally reduce operating cash flow and require additional capital to finance the business. We expect both of these trends to continue for the foreseeable future.

The Cancellation or Rescheduling of Orders May Cause Our Operating Results to Fluctuate.

The cancellation or rescheduling of orders may cause our operating results to fluctuate. Although we make every reasonable effort to maintain ongoing relationships with our customers, there is an ongoing risk that orders may be cancelled or rescheduled due to fluctuations in our customers’ business needs or overall market demand for our products. Additionally, although we serve more than 2,800 individual accounts, the cancellation or rescheduling of orders by larger customers may still have a material adverse effect on our operating results from time to time.

Our Business May be Negatively Impacted By Foreign Currency Fluctuations and Our Dependence on Foreign Suppliers.

In fiscal 2012, approximately 80% of our products were purchased from vendors in a variety of foreign countries. The products generally are purchased through purchase orders with the purchase price specified in U.S. dollars. Accordingly, we do not have exposure to fluctuations in the relationship between the dollar and various foreign currencies between the time of execution of the purchase order and payment for the product. To the extent that the dollar decreases in value relative to foreign currencies in the future, the price of the product in dollars for new purchase orders may increase.

The largest portion of our overseas purchases is from China. Since June 2010, the Chinese Yuan has increased approximately 7.2% relative to the U.S. Dollar. A continued increase in the value of the Yuan relative to the U.S. Dollar will likely result in an increase in the cost of products that we purchase from China.

As a result of the magnitude of our foreign sourcing, our business may be subject to risks, including the following:

If these risks limit or prevent us from acquiring products from foreign suppliers or significantly increase the cost of our products, our operations could be seriously disrupted until alternative suppliers are found, which could negatively impact our business.

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We Extend Credit to Our Customers Who May Be Unable to Pay In the Future.

We regularly extend credit to our customers. A significant percentage of our accounts receivable have been, and will continue to be concentrated among a relatively small number of automotive retailers and automotive parts distributors in the United States. Our five largest customers accounted for 86% and 83% of total accounts receivable as of December 29, 2012 and December 31, 2011, respectively. Management continually monitors the credit terms and credit limits of these and other customers. If any of these customers were unable to pay, our business and financial condition would be adversely affected.

The Loss of a Key Vendor Could Lead to Increased Costs and Lower Profit Margins.

The majority of the products we sell are purchased from a number of foreign vendors. If any of our existing vendors fail to meet our needs, we believe that sufficient capacity exists in the open market to supply any shortfall that may result. Nevertheless, it is not always possible to replace a key vendor without a disruption in our operations and replacement of a significant vendor is often at higher prices.

Limited Shelf Space May Adversely Affect Our Ability to Expand Our Product Offerings.

Since the amount of space available to a retailer and other purchasers of our products is limited, our products compete with other automotive aftermarket products, some of which are entirely dissimilar and otherwise non-competitive (such as car waxes and engine oil), for shelf and floor space. No assurance can be given that additional space will be available in our customers’ stores to support the expansion of the number of products that we offer.

If We Do Not Continue to Develop New Products and Bring Them to Market, Our Business, Financial Condition and Results of Operations Could Be Materially Impacted.

The development and production of new products is often accompanied by design and production delays and related costs typically associated with the development and production of new products. While we expect and plan for such delays and related costs, we cannot predict with precision the time and expense required to overcome these initial problems so that the products comply with specifications. There is a risk that we may not be able to introduce or bring to full-scale production new products as quickly as we expected in our product introduction plans, which could have a material adverse effect on our business, financial condition, and results of operations.

An Increase in Patent Filings by Original Equipment Manufacturers Could Negatively Impact Our Ability to Develop New Products.

We have seen an increase in patent requests for new designs made by original equipment manufacturers. If original equipment manufacturers are able to obtain patents on new designs at a rate higher than historical levels, we could be restricted or prohibited from selling aftermarket products covered by such items until such patents expire, which could have an adverse impact on our business.

Quality Problems with Our Products Could Damage Our Reputation and Adversely Affect Our Business.

We have experienced, and in the future may experience, reliability, quality, or compatibility problems in products after their production and sale to customers. Product quality problems could result in damage to our reputation, loss of customers, a decrease in revenue, litigation, unexpected expenses, and a loss of market share. We have invested and will continue to invest in our engineering, design, and quality infrastructure in an effort to reduce and eventually eliminate these problems; however, there can be no assurance that we can successfully remedy all of these issues. To the extent we experience significant quality problems in the future our business and results of operations may be negatively impacted.

Loss of Third-Party Transportation Providers Upon Whom We Depend or Increases in Fuel Prices Could Increase Our Costs or Cause a Disruption in Our Operations.

We depend upon third-party transportation providers for delivery of our products to us and to our customers. Strikes, slowdowns, transportation disruptions or other conditions in the transportation industry, including, but not limited to, shortages of truck drivers, disruptions in rail service, decreases in ship building or increases in fuel prices, could increase our costs and disrupt our operations and our ability to service our customers on a timely basis.

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We May Not Properly Execute, or Realize Anticipated Cost Savings or Benefits from, Our Ongoing Information Technology Initiatives.

Our success is partly dependent on properly executing, and realizing cost savings or other benefits from, our ongoing information technology initiatives. These initiatives are primarily designed to make us more efficient in the development, acquisition and distributions of our products, which is necessary in our highly competitive industry. These initiatives are often complex, and a failure to implement them properly may, in addition to not meeting projected cost savings or benefits, result in an interruption to our business functions.

Unfavorable Results of Legal Proceedings Could Materially Adversely Affect Us.

We are subject to various legal proceedings and claims that have arisen out of the ordinary course of our business which are not yet resolved and additional claims may arise in the future. Although we currently believe that resolving all of these matters, individually or in the aggregate, will not have a material adverse impact on our financial position, legal claims and proceedings are subject to inherent uncertainty and our view on these matters may change in the future. Regardless of merit, litigation may be both time-consuming and disruptive to our operations and cause significant expense and diversion of management attention. Should we fail to prevail in certain matters, we may be faced with significant monetary damages or injunctive relief that would materially adversely affect our business and financial condition and operating results.

We Have No History of Paying Regular Dividends And Do Not Intend to Pay Regular Dividends.

On December 5, 2012, we announced a special cash dividend of $1.50 per share payable on December 28, 2012 to shareholders of record at the close of business on December 17, 2012. This special cash dividend notwithstanding, we do not intend to pay regular cash dividends. Rather, for the foreseeable future, we intend to retain our earnings, if any, for the operation and continued expansion of our business.

Dorman’s Chairman of the Board and Chief Executive Officer and His Family Members Control the Company.

As of February 22, 2013, Steven L. Berman, our Chairman and Chief Executive Officer and director of Dorman Products, Inc., and his family members beneficially own approximately 31% of the outstanding Common Stock, have a controlling influence over the election of the Board of Directors and the outcome of most corporate actions requiring shareholder approval (including certain fundamental transactions) and the affairs of the Company. Such concentration of ownership may have the effect of delaying, preventing or deterring a change in control of the Company, could deprive shareholders of an opportunity to receive a premium for their common stock as part of a sale of the Company and might ultimately affect the market price of our common stock.

Our Success Depends on the Efforts of Our Management Team.

The success of our business will continue to be dependent upon Steven L. Berman, Chairman of the Board and Chief Executive Officer, Secretary and Treasurer, other executive officers and key employees and our ability to attract and retain other skilled managers. The loss of the services of any of these individuals for an extended period of time could have a material adverse effect on our business.

Our operations, revenues and operating results, and the operations of our third party manufacturers, suppliers and customers, may be subject to quarter to quarter fluctuations and disruptions from events beyond our or their control.

Our operations, revenues and operating results, as well as the operations of our third party manufacturers, suppliers and customers, may be subject to quarter to quarter fluctuations and disruptions from a variety of causes outside of our or their control, including work stoppages, market volatility, acts of war, terrorism, cyber incidents, pandemics, fire, earthquake, flooding, changes in weather patterns, weather or seasonal fluctuations or other climate-based changes, including hurricanes or tornadoes, or other natural disasters. If a major disruption were to occur at our operations or the operations of our third party manufacturers, suppliers or customers, it could result in harm to people or the natural environment, delays in shipments of products to customers or suspension of operations, any of which could have a material adverse effect on our business, revenues and operating results.

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Item 1B. Unresolved Staff Comments.

None

Item 2. Properties.

Facilities

We currently have 15 warehouse and office facilities located throughout the United States, Canada, China and India. Two of these facilities are owned and the remainder are leased. Our headquarters and principal warehouse facilities are as follows:

Item 3. Legal Proceedings.

We are a party to or otherwise involved in legal proceedings that arise in the ordinary course of business, such as various claims and legal actions involving contracts, competitive practices, trademark and patent rights, product liability claims and other matters arising out of the conduct of our business. In the opinion of management, none of the actions, individually or in the aggregate, would likely have a material financial impact on the Company and we believe the range of reasonably possible losses from current matters continues to be immaterial.

Item 4. Mine Safety Disclosures.

Not applicable

Item 4.1. Executive Officers of the Registrant.

Executive Officers of the Registrant.

The following table sets forth certain information with respect to our executive officers:

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Louis R. Arace joined the Company in January, 2012 as Senior Vice President, Supply Chain. From 2010 to 2012 Mr. Arace was a partner at Logistics Resources International, a distribution and transportation consultant, where he was responsible for improving the supply chain performance of the firm’s clients. Prior to joining Logistics Resources International, Mr. Arace served as Chief Supply Chain Officer for Nutrisystem, Inc. and Senior Vice President, Global Operations at Cardone Industries, Inc., a manufacturer and supplier of automotive replacement parts. He is a graduate of Messiah College and has earned his MBA from Pennsylvania State University.

Mathias J. Barton joined the Company in November 1999 as Senior Vice President, Chief Financial Officer. He became co-President of the Company in February 2011. Prior to joining the Company, Mr. Barton was Senior Vice President and Chief Financial Officer of Central Sprinkler Corporation, a manufacturer and distributor of automatic fire sprinklers, valves and component parts. From May 1989 to September 1998, Mr. Barton was employed by Rapidforms, Inc., a manufacturer of business forms and other products, most recently as Executive Vice President and Chief Financial Officer. He is a graduate of Temple University.

Joseph M. Beretta joined the Company in January 2004 as Senior Vice President, Product. He became co-President of the Company in February, 2011. Prior to joining the Company, Mr. Beretta was employed by Cardone Industries, Inc., most recently as its Chief Operating Officer. Cardone is a re-manufacturer and supplier of automotive replacement parts. He is a graduate of Oral Roberts University.

Steven L. Berman is Chairman of the Board, Chief Executive Officer, and Secretary-Treasurer of the Company. Mr. Berman became Chairman and Chief Executive Officer in January 2011 and Secretary-Treasurer in 1978. He previously held the positions of President and a director of the Company from October 24, 2007 to January 30, 2011. Prior to October 24, 2007, he served as Executive Vice President, Secretary-Treasurer and a director of the Company since its inception in 1978. Since the inception of the Company in October 1978 until October 25, 2007, Mr. Berman served as Executive Vice President. He attended Temple University.

Jeffrey L. Darby joined the Company in November 1998 as a National Account Manager. He became Senior Vice President of Sales and Marketing in February 2011. Prior to joining the Company, Mr. Darby worked for Federal Mogul Corporation/Moog Automotive, a automotive parts supplier, beginning in 1990. He holds an MBA Degree from Fairleigh Dickenson University and a B.A. Degree from William Paterson University.

Michael B. Kealey joined Dorman Products in November of 2002, as a Product Manager. He became Senior Vice President - Product in February 2011. He previously held the positions of Vice President - Product from January 2007 through January 2011, and Director - Product Management from April 2003 through December 2006. Prior to joining the company, Mr. Kealey was employed by Eastern Warehouse Distributors, Inc., a distributor of automotive replacement parts, most recently as Vice President - Purchasing. He attended Temple University.

Thomas J. Knoblauch joined the Company in April 2005 as Vice President and General Counsel. In May 2005, Mr. Knoblauch was appointed Assistant Secretary. Prior to joining the Company he was Corporate Counsel at SunGard Data Systems, Inc. a software and technology services company, from 1996 to 2000 and General Counsel at Rosenbluth International, Inc., a corporate travel company, from 2000 to May, 2005. He is a graduate of Widener University, St. Joseph’s University, the Widener University School of Law, and the Temple University Beasley School of Law Graduate Tax Program. Mr. Knoblauch is a member of both the Pennsylvania and New York Bar.

Matthew S. Kohnke joined Dorman Products in May 2002 as Vice President - Corporate Controller. He became Vice President and Chief Financial Officer of the Company in February 2011. Prior to joining the Company, Mr. Kohnke worked for Arthur Andersen LLP, beginning as an intern in January 1992 and advancing to manager in the Audit and Business Advisory practice. He is a graduate of Villanova University.

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PART II

Item 5. Market for Registrant’s Common Equity, Related Shareholder Matters and Issuer Purchases of Equity Securities.

Our shares of common stock are traded publicly on the NASDAQ Global Select Stock Market under the ticker symbol “DORM”. At February 25, 2013 there were 202 holders of record of common stock, representing more than 2,700 beneficial owners. The last price for our common stock on February 25, 2013, as reported by the NASDAQ Global Select Stock Market, was $34.30 per share. On December 28, 2012, we paid a special cash dividend to all common stockholders of record on December 17, 2012 of $1.50 for each share of common stock outstanding. We do not presently contemplate paying regular or special dividends in the foreseeable future. The range of high and low sales prices for our common stock for each quarterly period of fiscal 2012 and fiscal 2011 are as follows:

For the information regarding our equity compensation plans, see Item 12, Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

Stock Performance Graph. Below is a line graph comparing the cumulative total shareholder return for our common stock with the cumulative total shareholder return for the Automotive Parts & Accessories Peer Group of the Morningstar Group Index (formerly Hemscott Group Index) and the NASDAQ Composite Market Index for the period from December 29, 2007 to December 29, 2012. The Automotive Parts & Accessories Peer Group is comprised of 37 public companies and the information was furnished by Morningstar, Inc. through Zacks Investment Research, Inc. The graph assumes $100 invested on December 29, 2007 in our common stock and each of the indices, and that the dividends were reinvested when and as paid. In calculating the cumulative total shareholder returns, the companies included are weighted according to the stock market capitalization of such companies.

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Stock Repurchases

We periodically repurchase shares from the Dorman Products, Inc, 401(k) Retirement Plan and Trust (the “401(k) Plan”). Shares are generally purchased from the 401(k) Plan when participants elect to sell units as permitted by the 401(k) Plan or to leave the 401(k) Plan upon retirement, termination or other reasons. We purchased 70,208 shares from the 401(k) Plan during the fiscal year ended December 29, 2012.

During the last three months of the fiscal year ended December 29, 2012, we purchased shares of our Common Stock as follows:

Item 6. Selected Financial Data.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Cautionary Statement Regarding Forward Looking Statements

Certain statements in this document constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. While forward-looking statements sometimes are presented with numerical specificity, they are based on various assumptions made by management regarding future circumstances over many of which the Company has little or no control. Forward-looking statements may be identified by words including “anticipate,” “believe,” “estimate,” “expect,” and similar expressions. The Company cautions readers that forward-looking statements, including, without limitation, those relating to future business prospects, revenues, working capital, liquidity, and income, are subject to certain risks and uncertainties that would cause actual results to differ materially from those indicated in the forward-looking statements. Factors that could cause actual results to differ from forward-looking statements include but are not limited to competition in the automotive aftermarket industry, unfavorable economic conditions, loss of key suppliers, loss of third-party transportation providers, an increase in patent filings by original equipment manufacturers, quality problems, delay in the development and design of new products, space limitations on our customers’ shelves, concentration of the Company’s sales and accounts receivable among a small number of customers, the impact of consolidation in the automotive aftermarket industry, foreign currency fluctuations, timing and amount of customers’ orders of Company’s products, dependence on senior management and other risks and factors identified from time to time in the reports the Company files with the SEC. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those anticipated, estimated or projected. For additional information concerning factors that could cause actual results to differ materially from the information contained in this report, reference is made to the information in “Part I, Item 1A Risk Factors.”

Overview

We are a supplier of automotive and heavy duty truck replacement parts and fasteners, and service line products primarily for the automotive aftermarket. We market approximately 133,000 SKU’s many of which we design and engineer. These SKU’s are sold under our various brand names, under our customers’ private label brands or in bulk. We believe we are the dominant aftermarket supplier of original equipment dealer “exclusive” items. Original equipment dealer “exclusive” parts are those parts which were traditionally available to consumers only from original equipment manufacturers or salvage yards. These parts include, among other parts, intake manifolds, exhaust manifolds, oil cooler lines, window regulators, radiator fan assemblies, power steering pulleys, harmonic balancers, tire pressure monitor sensors, and keyless entry devices.

We generate over 90% of our revenues from customers in the North American automotive aftermarket, primarily in the United States and Canada. Our products are sold through automotive aftermarket retailers; national, regional and local warehouse distributors and specialty markets; and salvage yards. We distribute automotive replacement parts outside the United States, with sales into Europe, Mexico, the Middle East and Asia.

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Executive Overview

We achieved record net sales and net income in 2012. Net sales from continuing operations increased 11% over 2011 levels to $570.4 million, while net income from continuing operations increased 18% to $66.4 million. We believe our strong financial results have been driven by favorable industry dynamics, sales growth resulting from new product sales, continued investments in new product development and a commitment to process improvements.

The automotive aftermarket has benefited from some of the factors affecting the general economy, including the impact of the recent recession, continued high unemployment, and high gas prices. We believe vehicle owners have become more likely to keep their current vehicles longer and perform necessary repairs and maintenance in order to keep those vehicles well maintained as a result of these factors. According to data published by the Automotive Aftermarket Industry Association in 2012, the average age of vehicles on the road was 10.8 years as of December 2011. Another important statistic that impacts our business is the number of miles driven, which has remained essentially flat since 2009. However, the combination of vehicle age and miles driven accounts for a portion of our sales growth.

The overall automotive aftermarket in which we compete has benefited from the conditions mentioned above. However, our customer base has consolidated in recent years. As a result, our customers regularly seek more favorable pricing, product returns and extended payment terms when negotiating with us. We attempt to avoid or minimize these concessions as much as possible, but we have granted pricing concessions, increased customer payment terms and allowed higher level of product returns in certain cases. These concessions impact our profit levels and may require additional capital to finance the business. We expect our customers to continue to exert pressure on our margins as the customer base continues to consolidate.

We rely on new product development as a way to offset some of these customer demands and as our primary vehicle for growth. As such, new product development is a critical success factor for us. We have made incremental investments to increase our new product development efforts each year since 2003 in an effort to grow our business and strengthen our relationships with our customers. The investments are primarily in the form of increased product development resources, increased customer and end-user awareness programs and customer service improvements. These investments have enabled us to provide an expanding array of new product offerings and grow revenues at levels that exceed market growth rates.

In 2012, we introduced a new line of products to be marketed for the medium and heavy duty truck aftermarket. We believe that this market provides many of the same opportunities for growth that the automotive aftermarket has provided us over the past several years. Our focus here will be on Formerly Dealer Only parts as it is on the automotive side of the business. We launched the initial program with a limited offering, but have made additional investments in new product development efforts to expand our product offering. We currently have over 235 SKU’s in our medium and heavy duty product line. Revenues from this product line were less than 1% of our net sales in 2012.

We may experience significant fluctuations from quarter to quarter in our results of operations due to the timing of orders placed by our customers. Generally, the second and third quarters have the highest level of customer orders. The introduction of new products and product lines to customers may cause significant fluctuations from quarter to quarter.

We operate on a fifty-two, fifty-three week period ended on the last Saturday of the calendar year. The fiscal years ended December 29, 2012 and December 25, 2010 were fifty-two week periods. The fiscal year ended December 31, 2011 was a fifty-three week period.

Discontinued Operations

On September 21, 2011, we announced our plan to exit the international portion of our ScanTech business due to continued operating losses and to focus on growing our North American business. ScanTech was headquartered outside Stockholm, Sweden and distributed a line of Volvo and Saab replacement parts throughout the world. ScanTech’s results of operations have been presented as a discontinued operation in the Consolidated Statement of Operations.

Asset Write Downs

During the fourth quarter of fiscal 2010, we determined that certain acquired intangible assets were impaired. As such, we recorded an impairment charge of $1.0 million in fiscal 2010 to fully write-off these assets.

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Results of Operations

The following table sets forth, for the periods indicated, the percentage of net sales represented by certain items in our Consolidated Statements of Operations:

Fiscal Year Ended December 29, 2012 Compared to Fiscal Year Ended December 31, 2011

Net sales increased 11% over the prior year to $570.4 million from $513.4 million last year. Excluding the impact of an additional $4.8 million in sales due to a fifty-third week in fiscal 2011, revenues increased 12% over fiscal 2011 levels. Our revenue growth continues to be driven by overall strong demand for our products and higher new product sales.

Cost of goods sold, as a percentage of net sales decreased to 62.3% in fiscal 2012 from 63.1% in the same period last year. Lower transportation costs contributed approximately one-half of the difference. The remaining variance was primarily the result of a favorable sales mix towards higher margin products, and provisions for excess and obsolete inventory which were $1.0 million lower in fiscal 2012 than in fiscal 2011.

Selling, general and administrative expenses in fiscal 2012 increased 9% to $111.0 million from $101.6 million in fiscal 2011. The spending increase in fiscal 2012 was primarily the result of approximately $3.2 million of increased payroll expenses as we continue to invest in additional product management and other resources to support our product development and growth efforts, $1.7 million of higher incentive compensation expenses and $0.9 million of increased financing costs associated with our accounts receivable sales programs. However, selling, general and administrative expenses decreased to 19.4% of net sales from 19.8% of net sales as we continue to leverage our expenses over growing net sales.

Interest expense, net, was $0.1 million in fiscal 2012 and fiscal 2011.

Our effective tax rate increased to 36.2% in fiscal 2012 from 35.8% in the prior year. The effective tax rate in fiscal 2011 was favorably impacted by the 2011 receipt of tax exempt life insurance proceeds to fund an officer’s death benefit.

Fiscal Year Ended December 31, 2011 Compared to Fiscal Year Ended December 25, 2010

Net sales increased 17% to $513.4 million in fiscal 2011 from $438.2 million in fiscal 2010. Our revenue growth was driven by overall strong demand for our products, higher new product sales and the impact of one additional week’s sales in fiscal 2011. Excluding the additional one week of sales, net sales growth was 16% in fiscal 2011 compared to fiscal 2010.

Cost of goods sold, as a percentage of net sales increased to 63.1% in fiscal 2011 from 61.4% in fiscal 2010. Provisions for excess and obsolete inventory were $3.3 million higher in fiscal 2011 than in fiscal 2010. Also, higher product returns costs and an unfavorable change in sales mix each resulted in approximately one-half of the remaining variance.

Selling, general and administrative expenses in fiscal 2011 increased 10% to $101.6 million from $92.1 million in fiscal 2010. The spending increase in fiscal 2011 was primarily the result of approximately $9.2 million of increased payroll expenses related to investments in product management and other resources and $1.5 million of increased financing costs associated with our accounts receivable sales programs which was partially offset by $2.4 million of lower incentive compensation expenses in fiscal 2011 compared to fiscal 2010. Additionally, in fiscal 2010, we recorded a charge of $1.0 million to write-off certain intangible assets.

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Interest expense, net, was $0.1 million in fiscal 2011 and fiscal 2010.

Our effective tax rate decreased to 35.8% in fiscal 2011 from 37.3% in the prior year. The decrease is primarily due to the effect of lower provisions for state income taxes and the fiscal 2011 receipt of tax exempt life insurance proceeds used to fund an officer’s death benefit.

Liquidity and Capital Resources

Historically, we have financed our growth through a combination of cash flow from operations, accounts receivable sales programs provided by certain customers and through the issuance of senior indebtedness through our bank credit facility and senior note agreements. Cash and cash equivalents as of December 29, 2012 decreased to $27.7 million from $50.2 million as of December 31, 2011 due to our special cash dividend paid in December 2012. Working capital was $272.4 million at December 29, 2012 compared to $265.6 million at December 31, 2011. We had no long-term debt or borrowings under our Revolving Credit Facility at December 29, 2012 or December 31, 2011. Shareholders’ equity was $332.9 million at December 29, 2012 compared to $317.1 million at December 31, 2011.

Over the past several years we have continued to extend payment terms to certain customers as a result of customer requests and market demands. These extended terms have resulted in increased accounts receivable levels and significant uses of cash flow. We participate in accounts receivable sales programs with several customers which allow us to sell our accounts receivable to financial institutions to offset the negative cash flow impact of these payment terms extensions. During fiscal 2012 and fiscal 2011, we sold approximately $312.7 million and $208.8 million, respectively, under these programs. We expect continued pressure to extend our payment terms for the foreseeable future. Further extensions of customer payment terms will result in additional uses of cash flow or increased costs associated with the sale of accounts receivable.

We have a $30.0 million Revolving Credit Facility which expires in June 2015. Borrowings under the facility are on an unsecured basis with interest at rates ranging from LIBOR plus 75 basis points to LIBOR plus 250 basis points based upon the achievement of certain benchmarks related to the ratio of funded debt to earnings before interest, taxes, depreciation and amortization (“EBITDA”). The interest rate at December 29, 2012 was LIBOR plus 75 basis points (0.96%). There were no borrowings under the Revolving Credit Facility as of December 29, 2012. As of December 29, 2012, we had three letters of credit for approximately $0.9 million in the aggregate which were issued to secure ordinary course of business transactions. We had approximately $29.1 million available under the facility at December 29, 2012, net of these letters of credit. The loan agreement also contains covenants, the most restrictive of which pertain to net worth and the ratio of debt to EBITDA. As of December 29, 2012, we were in compliance with all financial covenants contained in the Revolving Credit Facility.

Off-Balance Sheet Arrangements

Our business activities do not include the use of unconsolidated special purpose entities, and there are no significant business transactions that have not been reflected in the accompanying financial statements.

Contractual Obligations and Commercial Commitments

We have future obligations for future minimum rental and similar commitments under noncancellable operating leases as well as contingent obligations related to outstanding letters of credit. These obligations as of December 29, 2012 are summarized in the tables below (in thousands):

We have excluded from the table above unrecognized tax benefits due to the uncertainty of the amount and period of payment. As of December 29, 2012, the Company has gross unrecognized tax benefits of $1.8 million (see Note 10, Income Taxes, to the Consolidated Financial Statements).

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Cash Flows

Below is a table setting forth the key lines of our Consolidated Statements of Cash Flows:

Cash provided by operating activities in fiscal 2012 increased by $10.8 million compared to fiscal 2011 primarily due to a $17.7 million increase in net income which was partially offset by a $3.0 million non-cash foreign exchange gain resulting from the substantial liquidation of our ScanTech subsidiary in fiscal 2012 and $1.7 million increase in working capital needs in fiscal 2012. Due to our growth during the periods of fiscal 2012 and fiscal 2011, accounts receivable, inventory and accounts payable increased.

Cash provided by operating activities in fiscal 2011 increased by $7.3 million compared to fiscal 2010 primarily due to a $7.1 million increase in net income in fiscal 2011 compared to fiscal 2010. Also, due to our growth over the periods of fiscal 2011 and fiscal 2010, accounts receivable, inventory and accounts payable increased.

Investing activities used $18.1 million of cash in both fiscal 2012 and fiscal 2011, and $11.5 million in fiscal 2010 as a result of additions to property, plant and equipment. Capital spending in each period was related to the following significant projects:

Cash used by financing activities increased $53.4 million in fiscal 2012 compared to fiscal 2011. On December 5, 2012 we announced a special cash dividend of $1.50 per share payable on December 28, 2012 to shareholders of record at the close of business on December 17, 2012. Total cash payments resulting from this dividend were $54.7 million in fiscal 2012. The remaining sources and uses of cash from financing activities in each period result from stock option activity and the repurchase of common stock from our 401(k) Plan.

Based on our current operating plan, we believe that our sources of available capital are adequate to meet our ongoing cash needs for at least the next twelve months.

Foreign Currency Fluctuations

In fiscal 2012, approximately 80% of our products were purchased from vendors in a variety of foreign countries. The products generally are purchased through purchase orders with the purchase price specified in U.S. dollars. Accordingly, we do not have exposure to fluctuations in the relationship between the dollar and various foreign currencies between the time of execution of the purchase order and payment for the product. To the extent that the dollar decreases in value relative to foreign currencies in the future, the price of the product in dollars for new purchase orders may increase.

The largest portion of our overseas purchases comes from China. Since June 2010, the value of the Chinese Yuan has increased approximately 7.2% relative to the U.S. Dollar. A continued increase in the value of the Yuan relative to the U.S. Dollar will likely result in an increase in the cost of products that we purchase from China.

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Impact of Inflation

The overall impact of inflation has not resulted in a significant change in labor costs or the cost of general services utilized. The cost of many commodities that are used in our products has fluctuated over time resulting in increases and decreases in the prices of our products. In addition, we have periodically experienced increased transportation costs as a result of higher fuel prices. We will attempt to offset cost increases by passing along selling price increases to customers, using alternative suppliers and by resourcing purchases to other countries. However there can be no assurance that we will be successful in these efforts.

Related-Party Transactions

We have a noncancelable operating lease for our primary operating facility from a partnership in which Steven L. Berman, our Chairman and Chief Executive Officer, and his family members are partners. Total annual rental payments each year to the partnership under the lease arrangement was $1.5 million in fiscal 2012 and was $1.4 million in fiscal 2011 and fiscal 2010. Our Audit Committee is responsible for reviewing and approving all related party transactions. In the opinion of our Audit Committee, the terms and rates of this lease are no less favorable than those which could have been obtained from an unaffiliated party.

Critical Accounting Policies

Our discussion and analysis of our financial condition and results of operations are based upon the Consolidated Financial Statements, which have been prepared in accordance with U.S. generally accepted accounting principles. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets and liabilities, the disclosure of contingent liabilities and the reported amounts of revenues and expenses. We regularly evaluate our estimates and judgments, including those related to revenue recognition, bad debts, customer credits, inventories, goodwill and income taxes. Estimates and judgments are based upon historical experience and on various other assumptions believed to be accurate and reasonable under the circumstances. Actual results may differ materially from these estimates due to different assumptions or conditions. We believe the following critical accounting policies affect our more significant estimates and judgments used in the preparation of our Consolidated Financial Statements.

Allowance for Doubtful Accounts. The preparation of our financial statements requires us to make estimates of the collectability of our accounts receivable. We specifically analyze accounts receivable and historical bad debts, customer creditworthiness, current economic trends and changes in customer payment patterns when evaluating the adequacy of the allowance for doubtful accounts. A significant percentage of our accounts receivable have been, and will continue to be, concentrated among a relatively small number of automotive retailers and warehouse distributors in the United States. Our five largest customers accounted for 86% and 83% of net accounts receivable as of December 29, 2012 and December 31, 2011, respectively. A bankruptcy or financial loss associated with a major customer could have a material adverse effect on our sales and operating results.

Revenue Recognition and Allowance for Customer Credits. Revenue is recognized from product sales when goods are shipped, title and risk of loss have been transferred to the customer and collection is reasonably assured. We record estimates for cash discounts, product returns and warranties, discounts and promotional rebates in the period of the sale (“Customer Credits”). The provision for Customer Credits is recorded as a reduction from gross sales and reserves for Customer Credits are shown as a reduction of accounts receivable. Actual Customer Credits have not differed materially from estimated amounts for each period presented. Amounts billed to customers for shipping and handling are included in net sales. Costs associated with shipping and handling are included in cost of goods sold.

Excess and Obsolete Inventory Reserves. We must make estimates of potential future excess and obsolete inventory costs. We provide reserves for discontinued and excess inventory based upon historical demand, forecasted usage, estimated customer requirements and product line updates. We maintain contact with our customer base in order to understand buying patterns, customer preferences and the life cycle of our products. Changes in customer requirements are factored into the reserves as needed.

Goodwill. We assess the qualitative factors which could affect the fair values of our reporting units. During fiscal 2012 and 2011 we determined that it was not more likely than not that the fair values of each reporting unit was less than its carrying amount.

Income Taxes. We follow the asset and liability method of accounting for deferred income taxes. Under this method, income tax expense is recognized for the amount of taxes payable or refundable for the current year and for the change in the deferred tax liabilities and assets for the future tax consequences of events that have been recognized in an entity’s financial statements or tax returns. We must make assumptions, judgments and estimates to determine our current provision for income taxes and also our deferred tax assets and liabilities and any valuation allowance to be recorded against a deferred tax asset. Our judgments,

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assumptions and estimates relative to the current provision for income taxes takes into account current tax laws, our interpretation of current tax laws and possible outcomes of current and future audits conducted by tax authorities. Changes in tax laws or our interpretation of tax laws and the resolution of current and future tax audits could significantly impact the amounts provided for income taxes in our Consolidated Financial Statements. Our assumptions, judgments and estimates relative to the value of a deferred tax asset takes into account predictions of the amount and category of future taxable income. Actual operating results and the underlying amount and category of income in future years could render our current assumptions, judgments and estimates of recoverable net deferred taxes inaccurate. Any of the assumptions, judgments and estimates mentioned above could cause our actual income tax obligations to differ from our estimates.

New and Recently Adopted Accounting Pronouncements

Refer to Note 2, New and Recently Adopted Accounting Pronouncements, to the Notes of Consolidated Financial Statements included in this annual report on Form 10-K, which is incorporated herein.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk.

Our market risk is the potential loss arising from adverse changes in interest rates. Substantially all of our available credit and accounts receivable sale programs bear interest rates tied to LIBOR. Under the terms of our Revolving Credit Facility and customer-sponsored programs to sell accounts receivable, a change in either the lender’s base rate, LIBOR or discount rates under the accounts receivable sale programs would affect the rate at which we could borrow funds thereunder. A one percentage point increase in LIBOR or the discount rates on the accounts receivable sale programs would increase our interest expense on our variable rate debt, if any, and accounts receivable financing costs by approximately $1.8 million in fiscal 2012 and $1.4 million in fiscal 2011. This estimate assumes that our variable rate debt balance and the level of sales of accounts receivable remains constant for an annual period and the interest rate change occurs at the beginning of the period. The hypothetical changes and assumptions may be different from what actually occurs in the future.

We have historically and do not intend to use derivative financial instruments for trading or to speculate on changes in interest rates or commodity prices. We are not exposed to any significant market risks, foreign currency exchange risks, or interest rate risks from the use of derivative instruments. We did not hold any foreign exchange forward contracts at December 29, 2012. At December 31, 2011, we had two foreign exchange forward contracts outstanding to sell forward 10 million Swedish Krona to receive approximately $1.4 million. The fair value of these forward contracts was a liability of approximately $13,000 at December 31, 2011.

Item 8. Financial Statements and Supplementary Data.

Our financial statement schedule that is filed with this annual report on Form 10-K is listed in “Part II - Item 15 Exhibits, Financial Statements, Schedules.”

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Report of Independent Registered Public Accounting Firm

The Board of Directors and Stockholders

Dorman Products, Inc.:

We have audited the accompanying consolidated balance sheets of Dorman Products, Inc. and subsidiaries as of December 29, 2012 and December 31, 2011, and the related consolidated statements of operations, comprehensive income, shareholders’ equity, and cash flows for each of the years in the three-year period ended December 29, 2012. In connection with our audits of the consolidated financial statements, we also have audited the financial statement schedule listed under Item 15(a)(2). These consolidated financial statements and financial statement schedule are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated 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, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of Dorman Products, Inc. and subsidiaries as of December 29, 2012 and December 31, 2011, and the results of their operations and their cash flows for each of the years in the three-year period ended December 29, 2012, in conformity with U.S. generally accepted accounting principles. Also in our opinion, the related 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 also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), Dorman Products, Inc.’s internal control over financial reporting as of December 29, 2012, based on criteria established in Internal Control - Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO), and our report dated March 1, 2013 expressed an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting.

KPMG LLP

Philadelphia, PA

March 1, 2013

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DORMAN PRODUCTS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS

See accompanying Notes to Consolidated Financial Statements

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DORMAN PRODUCTS, INC.AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

See accompanying Notes to Consolidated Financial Statements

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DORMAN PRODUCTS, INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

See accompanying Notes to Consolidated Financial Statements.

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DORMAN PRODUCTS, INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY