Microbot Medical Inc. - Annual Report: 2013 (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, 2013

or

COMMISSION FILE NUMBER 0-19871

STEMCELLS, INC.

(Exact name of Registrant as specified in its charter)

Registrant’s telephone number, including area code:

(510) 456-4000

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 Section 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 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 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. (Check one):

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

Aggregate market value of common stock held by non-affiliates at June 30, 2013: $66,836,311. Inclusion of shares held beneficially by any person should not be construed to indicate that such person possesses the power, direct or indirect, to direct or cause the direction of management policies of the registrant, or that such person is controlled by or under common control with the Registrant.

Common stock outstanding at March 3, 2014: 55,419,116 shares.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s definitive Proxy Statement relating to the registrant’s 2014 Annual Meeting of Stockholders to be filed with the Commission pursuant to Regulation 14A are incorporated by reference in Part III of this report.

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FORWARD LOOKING STATEMENTS

THIS REPORT CONTAINS FORWARD-LOOKING STATEMENTS AS DEFINED UNDER THE FEDERAL SECURITIES LAWS. ACTUAL RESULTS COULD VARY MATERIALLY. FACTORS THAT COULD CAUSE ACTUAL RESULTS TO VARY MATERIALLY ARE DESCRIBED HEREIN AND IN OTHER DOCUMENTS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION. READERS SHOULD PAY PARTICULAR ATTENTION TO THE CONSIDERATIONS DESCRIBED IN THE SECTION OF THIS REPORT ENTITLED “MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS” AS WELL AS ITEM 1A UNDER THE HEADING “RISK FACTORS.” FORWARD-LOOKING STATEMENTS SPEAK ONLY AS OF THE DATE OF THIS REPORT. WE DO NOT UNDERTAKE ANY OBLIGATION TO PUBLICLY UPDATE ANY FORWARD-LOOKING STATEMENTS.

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NOTE REGARDING REFERENCES TO OUR COMMON STOCK

Throughout this Form 10-K, the words “we,” “us,” “our,” and “StemCells” refer to StemCells, Inc., including our directly and indirectly wholly-owned subsidiaries. “Common stock” refers to the common stock of StemCells, Inc., $0.01 par value.

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PART I

Overview

StemCells, Inc. is engaged in the research, development, and commercialization of stem cell therapeutics and related tools and technologies for academia and industry. We believe that understanding cells and cell biology, and in particular stem cells, will play an increasingly important role in the understanding of human diseases and in the discovery of new medical therapies. Consequently, we are focused on developing and commercializing (i) stem and progenitor cells as the basis for novel therapeutics and therapies, and (ii) cells and related tools and technologies to enable stem cell-based research and drug discovery and development.

Our primary research and development efforts are focused on identifying and developing stem and progenitor cells as potential therapeutic agents. Our lead product development program is our CNS Program, in which we are developing applications for HuCNS-SC^® cells, our proprietary human neural platform technology. We estimate that degenerative conditions of the central nervous system (CNS) currently affect more than 30 million people in the United States¹.

We are currently in clinical development with our HuCNS-SC cells for a range of diseases and disorders of the central nervous system. The CNS consists of the brain, spinal cord and eye, and we are currently the only stem cell company in clinical development for indications in all three organs comprising the CNS, specifically:

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In our tools and technologies programs, we are engaged in developing and commercializing applications of our technologies to enable stem cell-based research. We currently market a range of proprietary cell culture products, research grade human cells, and antibody reagents under the SC Proven^® brand. Our cell culture products include iSTEM^®, GS1-R^®, GS2-M^®, RHB-A^®, RHB-Basal^®, NDiff227™, NDiff^® N2, and NDiff N27™ supplements. Our cell lines available for research use include human neural stem cells and hFB101™, ultra primary human fibroblasts for genetic reprogramming. Our antibody reagents include STEM24™, STEM101^®, STEM121^®, and STEM123^®, which can be used for cell detection, isolation and characterization. Academic and industrial laboratories conducting stem cell research need specialized cell culture products and reagents for the derivation, growth, maintenance, and manipulation of stem cells, as well as their detection, isolation and characterization in both in vitro and in vivo models. As this type of research continues to grow, the market for such cell culture products and reagents should also continue to expand. We are seeking to leverage our proprietary technologies, including technologies relating to embryonic stem cells, induced pluripotent stem (iPS) cells, and tissue-derived (adult) stem cells, for use in stem cell-based research. Several of the cell technologies and intellectual property related to our enabling cell technologies programs were acquired in April 2009 through our acquisition of substantially all of the operating assets and liabilities of Stem Cell Sciences Plc (SCS).

The Potential of Our Tissue-Derived Cell-Based Therapeutics

Stem cells are “building block” cells as they produce all the mature functional cell types found in normal organs. Stem cells have two defining characteristics: (i) they produce all of the mature cell types of the particular organ, and (ii) they self renew — that is, some of the cells developed from stem cells are themselves new stem cells. Progenitor cells are cells that have already developed from stem cells, but can still produce one or more mature cell types within an organ. Stem cells are rare; to date only four human stem cells have been identified and characterized in vivo: (i) the hemotopoietic stem cell, (ii) the mesenchymal stem cell, (iii) the neural stem cell, and (iv) the embryonic stem cell. Because of this self-renewal property, we believe that stem cell-based therapies may have the potential to return an impaired organ to proper function for the life of the patient.

Many degenerative diseases are caused by the loss of normal cellular function in a particular organ. When cells are damaged or destroyed, they no longer produce, metabolize or accurately regulate the many substances essential to life. There is no technology existing today that can deliver these essential substances precisely to the sites of action, under the appropriate physiological regulation, in the appropriate quantity, or for the duration required to cure the degenerative condition. Cells, however, can do all of this naturally. Transplantation of stem or progenitor cells may therefore prevent the loss of, or even generate new, functional cells and thereby potentially maintain or restore organ function and the patient’s health.

We are focused on identifying and purifying tissue-derived stem and progenitor cells for use in homologous therapy. Homologous therapy means the use of cells derived from a particular organ to treat a disease of that same organ (for example, use of brain-derived neural stem cells for treatment of CNS disorders). Tissue-derived stem cells are developmentally pre-programmed to become the mature functional cells of the organ from which they were derived. We believe that homologous use of purified, unmodified tissue-derived cells is the most direct way to provide for engraftment and differentiation into functional cells, and should minimize the risk of transplantation or growth of unwanted cell types.

We use cells derived from donated tissues, which are supplied to us in compliance with all applicable state and federal regulations. We are not involved in any activity directed toward human cloning, nor do we have any

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plans to start such activities. We are currently developing embryonic stem cells and iPS cells as potential research tools. We are not currently developing embryonic or induced pluripotent stem cells for therapeutic use.

Business Strategy

Our aim is to create a sustainable business based on our belief that understanding cells and cell biology will play an increasingly important role in life science research and in the discovery, development and implementation of new medical therapies. Our strategy has been to identify multiple types of human stem and progenitor cells with therapeutic and commercial importance, to develop techniques and processes to purify these cells for direct transplant and to expand and bank these cells. We are currently focused on advancing these cells through clinical development and into commercialized cell-based therapeutic products.

The fundamental competencies required to execute this strategy are knowledge and expertise in cell biology, particularly stem cell biology, and a commitment to rigorous and robust research and development. We believe that these competencies are critical to identifying, characterizing and understanding cells with therapeutic potential and importance.

Consequently, we have made significant investments in our research and development, clinical and regulatory, and cell processing and process development capabilities. Our management and staff have many years of experience in the stem cell field and in developing potential cell therapies. Two of the four human stem cells identified and characterized to date (the hematopoietic and neural stem cells) were discovered by scientists who are currently on our staff, and we believe we were the first company to receive authorization from the FDA to conduct a clinical trial of a purified neural stem cell product candidate, as well as the first to complete such a clinical trial. We are committed to proving that “groundbreaking science,” especially in the field of stem cell biology, has the potential to create truly “breakthrough medicine.”

Many of our core competencies in cell biology have applicability beyond the development of therapeutic products. Therefore, another element of our business strategy is to leverage these core competencies to develop non-therapeutic applications for our cell technologies, which we believe represent nearer-term commercial opportunities. As scientific and medical research increasingly focuses on stem cells and cell biology, our technologies are expected to have utility as tools to help enable this research. We currently market specialized cell culture products and antibody reagents through our SC Proven product line and are seeking to develop and commercialize applications of our technologies for use in stem cell-based research.

Further, a key element of our business strategy is to obtain patent protection for the compositions, processes and uses of multiple types of cells, as well as for those technologies that appear applicable and useful to enable cell-based research. We believe that patent protection will be available to the first to identify and isolate any of the finite number of different types of human stem and progenitor cells, and the first to define methods to culture such cells, making the commercial development of cell-based therapeutics and enabling applications financially feasible. In addition to discovering and developing technologies in-house, we have obtained from various academic and commercial institutions rights to certain inventions relating to stem and progenitor cells, cell culture media, and technologies to reprogram, isolate and manipulate cells. We expect to continue to expand our search for, and to seek to acquire rights from third parties relating to, new stem and progenitor cells and cell technologies. We have created an extensive patent estate, see “Patents, Proprietary Rights and Licenses,” below.

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Therapeutic Product Development Programs

Overview

The following table summarizes the current status of, and the anticipated initial indications for, our therapeutic product development program. A more detailed discussion of each of these follows the table.

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Many neurodegenerative diseases involve the failure of central nervous system tissue (i.e., the brain, spinal cord and eye) due to the loss of functional cells. Our CNS Program is initially focusing on developing clinical applications in which transplanting HuCNS-SC cells would protect or restore organ function of the patient before such function is irreversibly damaged or lost due to disease progression. Our initial target indications are (i) Pelizeaus-Merzbacher Disease, and more generally, diseases in which deficient myelination plays a central role, such as cerebral palsy or multiple sclerosis; (ii) spinal cord injury; (iii) Alzheimer’s disease, and (iv) disorders in which retinal degeneration plays a central role, such as age-related macular degeneration or retinitis pigmentosa. These disorders affect a significant number of people in the United States and there currently are no effective long-term therapies for them.

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Our platform technology, HuCNS-SC cells, is a purified and expanded composition of normal human neural stem cells. Alternative therapies based on cells derived from cancer cells, embryonic stem cells, iPS cells, animal-derived cells, or unpurified mixes of cell types have a significantly higher safety hurdle to overcome and while they may provide an effective therapy, technologies to remove potentially harmful cells are still being developed and tested. Furthermore, our HuCNS-SC cells can be directly transplanted, unlike embryonic stem cells or iPS cells, which require one or more prerequisite differentiation steps prior to administration in order to preclude teratoma formation (tumors of multiple differentiated cell types). It is still unclear whether cellular transplants derived from embryonic stem cells or iPS cells can avoid forming teratomas or other abnormal cellular structures due to contaminating cell types in the transplant product.

Our preclinical research has shown in vivo that HuCNS-SC cells engraft, migrate, differentiate into neurons and glial cells, and survive for as long as one year with no sign of tumor formation or adverse effects. Moreover, the HuCNS-SC cells were still producing progeny cells at the end of the test period. These findings show that our neural stem cells, when transplanted, act like normal neural stem cells, suggesting the possibility of a continual replenishment of normal human neural cells in transplant recipients. In the longer term, then, we believe stem cells have the potential to restore or replace lost cells and cellular function.

We hold a substantial portfolio of issued and allowed patents in the neural stem cell field, which cover the isolation, expansion and use of neural stem and progenitor cells, as well as the compositions of the cells themselves. See “Patents, Proprietary Rights and Licenses,” below.

Diseases and Disorders of the Brain

Pelizaeus-Merzbacher Disease (PMD).

Pelizaeus-Merzbacher disease, a rare, degenerative, central nervous system disorder, is one of a group of genetic disorders known as leukodystrophies. Leukodystrophies involve abnormal growth of the myelin sheath, which is the fatty substance that surrounds nerve fibers in the brain and spinal cord. PMD is most commonly caused by a genetic mutation that affects an important protein found in myelin, proteolipid protein. PMD is most frequently diagnosed in early childhood and is associated with abnormal eye movements, abnormal muscle function, and in some cases, seizures. The course of the disease is marked by progressive neurological deterioration resulting in premature death.

In February 2012, we completed a Phase I clinical trial in PMD. A total of four patients were transplanted with HuCNS-SC cells and were evaluated periodically over a 12-month period. The study was designed to help detect evidence of new myelin, including by magnetic resonance imaging (MRI) of the brain, changes in neuropsychological tests of development and cognitive function, and clinical changes in neurological function. The trial was conducted at the University of California, San Francisco. In October 2012, we published the results of the trial in Science Translational Medicine, a peer-reviewed journal. The clinical data from this study showed evidence of new myelin in all four patients who were transplanted with HuCNS-SC cells. In addition, three of the four patients showed modest gains in neurological function; the fourth patient remained stable. The data also showed that the cells, the transplantation procedure and the immunosuppression regimen were all well tolerated.

In our preclinical research, we have shown that HuCNS-SC cells differentiate into oligodendrocytes, the myelin producing cells, and produce myelin. We have transplanted HuCNS-SC cells into the brain of the mutant shiverer mouse, which is deficient in myelin, and shown widespread engraftment of human cells that matured into oligodendrocytes, and that the human oligodendrocytes myelinated the mouse axons.

Other Myelin Disorders.

Loss of myelin characterizes conditions such as multiple sclerosis, cerebral palsy and certain genetic disorders (for example, Krabbe’s disease and metachromatic leukodystrophy). Loss of myelin can also play a role in certain spinal cord indications. Based on our preclinical data, we believe our HuCNS-SC product candidate may have applicability to a range of myelin disorders.

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Neuronal Ceroid Lipofuscinosis (NCL; also known as Batten disease).

Neuronal ceroid lipofuscinosis, which is often referred to as Batten disease, is a neurodegenerative disease that affects infants and young children. Infantile and late infantile NCL are brought on by inherited genetic mutations which result in either a defective or missing enzyme, leading to the accumulation of cellular waste product in various neuronal cell types. This accumulation eventually interferes with normal cellular and tissue function, and leads to seizures and progressive loss of motor skills, sight and mental capacity. Today, NCL is always fatal.

In January 2009, we completed a six-patient Phase I clinical trial of our HuCNS-SC cells in infantile and late infantile NCL. We believe that this clinical trial was the first FDA-authorized trial to evaluate purified human neural stem cells as a potential therapeutic agent. The trial data demonstrated that the HuCNS-SC cells, the transplantation procedure and the immunosuppression regimen were well tolerated by all six patients, and the patients’ medical, neurological and neuropsychological conditions, following transplantation, appeared consistent with the normal course of the disease. In addition to this favorable safety profile, there was evidence of engraftment and long-term survival of the HuCNS-SC cells. This Phase I trial was conducted at OHSU Doernbecher Children’s Hospital in Oregon.

Our preclinical data demonstrate that HuCNS-SC cells, when transplanted in a mouse model of infantile NCL, engraft, migrate throughout the brain, produce the relevant missing enzyme, measurably reduce the toxic storage material in the brain, protect host neurons so that more of them survive, and delay the loss of motor function compared to a control group of non-transplanted mice. A summary of this data was published in September 2009 in the peer-reviewed journal Cell Stem Cell. We have also demonstrated in vitro that HuCNS-SC cells produce the enzyme that is deficient in late infantile NCL.

Alzheimer’s Disease.

Alzheimer’s disease is a progressive, fatal neurodegenerative disorder that results in loss of memory and cognitive function. Today, there is no cure or effective treatment option. According to the Alzheimer’s Association, an estimated 5.2 million Americans have Alzheimer’s disease, including nearly 5 million people aged 65 and older. The prevalence of Alzheimer’s disease is expected to increase rapidly as a result of our aging population.

In July 2012, we reported data that showed that our HuCNS-SC cells restored memory and enhanced synaptic function in two animal models relevant to Alzheimer’s disease. This research was a result of a collaboration we entered into with a world renowned leader in Alzheimer’s disease research at the University of California, Irvine (UCI) to study the therapeutic potential of our HuCNS-SC cells in Alzheimer’s disease. Our collaborator’s published research had shown that mouse neural stem cells enhance memory in a mouse model of Alzheimer’s disease, and the goal of the collaboration was to replicate these results using our human neural stem cells.

Previously, we conducted studies of our HuCNS-SC cells in another model of Alzheimer’s disease as part of a collaboration with researchers at the McLaughlin Research Institute. This research, which was funded by a National Institutes of Health (NIH) grant, demonstrated that our HuCNS-SC cells are capable of engrafting and surviving in the hostile environment reflective of an Alzheimer’s brain, which characteristically features abnormal accumulations of brain lesions called plaques and tangles.

In September 2012, the governing board of the California Institute of Regenerative Medicine (CIRM) approved our application for a Disease Team Therapy Development Research Award for the study of HuCNS-SC cells as a potential treatment for Alzheimer’s disease. We committed to filing an IND by mid-2017, however, we are diligently exploring ways to accelerate this milestone and currently anticipate filing by mid-2016. In accordance with the award, in April 2013, we entered into an agreement with the California Institute for

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Regenerative Medicine (CIRM) under which CIRM will provide up to approximately $19.3 million as a forgivable loan, in accordance with mutually agreed upon terms and conditions and CIRM regulations. We received, under the CIRM Loan Agreement, an initial disbursement of $3.8 million in July 2013 and a subsequent disbursement of $3.8 million in January 2014.

Diseases and Disorders of the Spinal Cord

According to a study initiated by the Christopher and Dana Reeve Foundation, an estimated 1.3 million people in the United States are living with chronic spinal cord injury. There are no therapies today that can address the paralysis or loss of function caused by a spinal cord injury, but neural stem cells may have the potential to provide a novel therapeutic approach.

We are conducting a Phase I/II clinical trial to evaluate our HuCNS-SC cells as a treatment for chronic spinal cord injury. The trial was initiated at University Hospital Balgrist in Zurich and was authorized by Swissmedic, the regulatory agency for therapeutic products in Switzerland. A total of twelve patients are expected to enroll in the study, all of whom will be three to twelve months post-injury. The study will follow a progressive study design, beginning with patients with complete injuries and then enrolling patients with incomplete injuries, all as classified by the American Spinal Injury Association Impairment Scale (AIS). In addition to assessing safety, the trial will evaluate preliminary efficacy using defined clinical endpoints, such as changes in sensation, motor function, and bowel/bladder function. In February 2013, we reported that the first patient cohort, all of whom had complete injuries classified as AIS A, had completed the trial, and that data from this first cohort showed that two of the three patients showed multi-segment gains in sensory function compared to pre-transplant baseline. The gains in sensory function were first observed at the six month assessment and persisted to the 12 month assessment. The third patient remained stable. To accelerate patient enrollment, we have expanded the trial from a single-site, single-country study to a multi-site, multi-country program. The trial is currently being conducted in Switzerland, Canada and the United States. As of February 2014, a total of eleven patients have been dosed with our HuCNS-SC cells in this trial and we expect to complete enrollment of the final patient in the first quarter of 2014.

The results of numerous preclinical studies demonstrate the therapeutic potential of our human neural stem cells for the treatment of spinal cord injury. Using a mouse model of spinal cord injury, our collaborators at the Reeve-Irvine Research Center at the University of California, Irvine have shown that our HuCNS-SC cells have the potential to protect and regenerate damaged nerves and nerve fibers, and that injured mice transplanted with our HuCNS-SC cells showed improved motor function compared to control animals. Inspection of the spinal cords from the treated mice showed significant levels of human neural cells derived from the transplanted stem cells. Some of these cells were oligodendrocytes, the specialized neural cell that forms the myelin sheath around axons, while others had become neurons and showed evidence of synapse formation, a requirement for proper neuronal function. The researchers then selectively ablated the human cells, and found that the functional improvement was lost, thus demonstrating that the human cells had played a direct role in the functional recovery of the transplanted mice. Moreover, our preclinical studies show that our human neural stem cells enable a significant and persistent recovery of motor function when transplanted in spinal cord-injured mice at both sub-acute and chronic injury time points.

In July 2012, the governing board of CIRM approved our application for a Disease Team Therapy Development Research Award for the study of HuCNS-SC cells as a potential treatment for cervical spinal cord injury. Under this disease team program, CIRM would have provided up to $20 million in the form of a forgivable loan. However, in March 2013, we elected not to borrow these funds from CIRM.

Diseases and Disorders of the Eye

The retina is a thin layer of neural cells that lines the back of the eye and is responsible for converting external light into neural signals. A loss of function in retinal cells leads to impairment or loss of vision. The

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most common forms of retinal degeneration are age-related macular degeneration (AMD) and retinitis pigmentosa. AMD is the leading cause of vision loss and blindness in people over the age of 55 and afflicts some 30 million people worldwide.

In June 2012, we initiated a Phase I/II clinical trial in dry age-related macular degeneration, the more common form of AMD, and in October 2012, the first patient was enrolled and dosed with HuCNS-SC cells. The trial, which was authorized by the FDA in January 2012, is expected to enroll a total of 16 patients and will evaluate the safety and preliminary efficacy of our HuCNS-SC cells as a treatment for dry AMD. Patients’ vision will be evaluated using conventional methods of ophthalmological assessment at predetermined intervals over a one-year period. This trial is being conducted at three sites in the United States, and as of February 2014, we completed enrollment of the first of two planned patient cohorts. We expect to complete enrollment of the second cohort consisting of eight patients by the end of the second quarter of 2014.

Our preclinical data have shown that our HuCNS-SC cells, when transplanted in a well-established animal model of retinal degeneration, engraft long-term, can protect photoreceptors (the key cells involved in vision) from progressive degeneration, and can slow or prevent loss of visual function. In this model, called the Royal College of Surgeons (RCS) rat, a genetic mutation causes dysfunction of the retinal pigmented cells, which leads to progressive loss of the photoreceptors and ultimately, loss of visual function in the rat. Our preclinical data shows that our human neural stem cells protect both rod and cone photoreceptors in the eye from progressive degeneration and preserve visual function long term. The cone photoreceptors are light sensing cells that are highly concentrated within the macula of the human eye, and the ability to protect these cells suggests a promising approach to treating AMD. A summary of our preclinical data was featured as the cover article in February 2012 edition of the international peer-reviewed European Journal of Neuroscience.

Other CNS Collaborations.

We have collaborated on a number of research programs to assess both the in vitro potential of the HuCNS-SC cells and the effects of transplanting HuCNS-SC cells into various preclinical animal models. One such collaboration was with researchers at the Stanford University School of Medicine that evaluated our human neural stem cells in animal models of stroke. The results of these studies demonstrated the targeted migration of the cells toward the stroke lesion and differentiation toward the neuronal lineage. Another study with researchers at Stanford’s School of Medicine demonstrated that HuCNS-SC cells labeled with magnetic nanoparticles could non-invasively track the survival and migration of human cells within the brain. We continue to search for and evaluate, promising collaborations to supplement our efforts to develop and commercialize our proprietary human neural platform technology.

Tools and Technologies Programs

Overview

Cells, and stem cells in particular, are an important resource for researchers seeking to understand human diseases, advance medical research and develop more effective therapies. Stem cells provide potentially unlimited sources of different cell types owing to their ability to be expanded and subsequently differentiated into particular cell types. Embryonic stem cells, for example, have the ability to become any one of the more than 200 specialized cell types found in the human body (they are said to be pluripotent); induced pluripotent stem (iPS) cells also possess this ability. Because of this versatility, these cells are valuable tools for examining and researching the fundamental biology of cells and the pathways involved in early development and tissue formation. In recent years, the pharmaceutical industry has become increasingly interested in using stem cell-based assays in its drug discovery and development efforts. Academia and industry use specialty cell culture products and antibody reagents to enable stem cell-based research and drug discovery and development. We sell specialty cell culture products and antibody reagents under our SC Proven brand.

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Specialty Cell Culture Products and Antibody Reagents

Stem cell research is a growing and highly specialized field. Because of their nature, stem and progenitor cells are rare and they require specific conditions to survive and thrive. For this reason, researchers require specialized cell culture products that enable the derivation, growth, maintenance, and manipulation of such cells. One of the greatest challenges facing researchers is the limited quality and quantity of available stem and progenitor cells. The challenge is in maintaining the pluripotency or multipotency of stem or progenitor cells in culture, i.e., keeping these cells from differentiating into other cell types, which is their natural tendency. Our cell biology expertise has enabled us to develop and commercialize proprietary cell culture products to optimize the derivation, growth, maintenance, and differentiation of stem cells. In contrast to common industry practice, we have developed media formulations that are free of animal serum and feeder cells (helper cells added to promote cell growth), which are known sources of undesirable agents affecting stem cell performance and safety.

Our current range of cell culture products, which are sold under the SC Proven brand, includes iSTEM, GS1-R, GS2-M, RHB-A, RHB-Basal, NDiff N2, and NDiff 227. The following table describes each of these in more detail:

We also currently market a number of antibody reagents for use in cell detection, isolation and characterization. These reagents are also under the SC Proven brand. The following table describes each of these in more detail:

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We also market a number of human cell lines for use in research, including human neural stem cells derived from different areas of the CNS as well as hFB101, ultra primary human fibroblasts for use in genetic reprogramming and the creation of human IPS cells.

Other products marketed under SC Proven include total cell genomic DNA (gDNA), RNA and protein lysate reagents purified from homogenous stem cell populations for intra-comparative studies, such as Epigenetic fingerprinting, Southern, Western and Northern blots, PCR, RT-PCR, and microarrays. This range of purified stem cell line lysates includes:

Other Technologies

In addition to our cell therapeutics and research reagent programs, we hold a number of “non-core” technologies which we feel present licensing opportunities, such as technologies for the generation of transgenic rats.

Transgenic Rat Program.

As part of our acquisition of assets from SCS in April 2009, we acquired exclusive rights to an intellectual property portfolio that broadly covers rat pluripotent stem cells, methods for using these cells to generate transgenic rats, and media for the culturing of these cells. This intellectual property was based upon research done at the University of Edinburgh, which showed for the first time the successful derivation and culture of true germline competent rat ES cells required for precise genetic engineering.

In August 2010, researchers demonstrated for the first time the creation of genetically modified rats using rat pluripotent cells that have been gene targeted via homologous recombination, a method which involves adding DNA sequences to the cells to delete (‘knock-out’), add (‘knock-in’) or otherwise modify genes of interest. This work resulted in the successful generation of knock-out rats missing the tumor suppressor gene p53 and served as a proof-of-principle for creating genetically engineered rats using rat ES cells. Prior to this breakthrough, these types of genetic manipulations were only possible in mice, and genetically engineered mice are widely used as disease models. While both mice and rats are used as animal models of human disease, aspects of the rat’s physiology, behavior, and metabolism are closer to the human, making rats the preferred species for drug development and studying human disease. Moreover, the rat cells used to generate these genetically engineered rats were cultured using a proprietary ‘2i’ inhibitor-based media formulation marketed as part of our SC Proven line of specialty cell culture products under the product name “GS1-R.” GS1-R is the first and only commercially available medium shown to enable the derivation and long-term maintenance of the true rat pluripotent cells required for precise genetic manipulation.

We believe that over the past few years a number of researchers have used our rat pluripotent cell technology to derive different knock-out and knock-in rat models. And, over this time, the first of the patents in this portfolio issued (GB Patent No. 2451523), and the proprietary media patent application was allowed in Europe (EPO Patent No. 1999249). We are therefore exploring our rat pluripotent cell technology and our inhibitor-based media as licensing and commercial opportunities.

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Contract Services and Supply Agreements

Our team members have been at the forefront of the research, development, manufacture, and clinical translation of various different stem cells and cell-based therapies for over 20 years. We have demonstrated expertise in the development and implementation of state-of-the-art cell separation devices, bioreactors, closed systems, and robotic platforms for manufacture of cells at the required scales. Leveraging this expertise, we now offer contract services for process development, process scale-up/scale-out and production, including use of our automated TAP Biosystems CompacT^® SelecT Robotic platform.

In an extension of the process development and production services we have been contracted to scale-up and supply quantities of cell lines, reagents, cell line derivatives, and assay protocols for use in client’s drug development and other programs.

Our clients include the service division of a global biotechnology company developing new medicines, and a world-renowned scientific research institute.

Operations

Manufacturing

We have made considerable investments in our manufacturing operations. Our team includes world-recognized experts with proven track records in the development, manufacture and delivery of a range of different cell-based products. For clinical trials, our highly-qualified personnel manufacture cell products in clean room environments in compliance with current Good Manufacturing Practice (cGMP) and to quality standards that meet US as well as international regulatory requirements. By combining expertise and experience, we believe our expandable and bankable cell products can ultimately be manufactured and distributed at commercial scale as “stem cells in a bottle,” much like an off-the-shelf pharmaceutical product. We believe we also have sufficient ability to manufacture the cell culture media and reagent products that we are currently selling commercially, and that we have sufficient resources to add additional media and reagent manufacturing capacity should the business need arise.

Marketing

Because of the early stage of our stem and progenitor cell-based therapeutic product development programs, we have not yet addressed questions of channels of distribution or marketing of potential future products. We sell and ship our proprietary cell culture products directly from our facility in Cambridge, U.K. Customers can order these products through our dedicated website (www.scproven.com). In addition, we have a number of co-exclusive distribution agreements with Millipore Corporation for the marketing and sale of certain of our cell culture products, including HEScGRO and ESGRO Complete.

Employees

As of December 31, 2013, we had 58 full-time employees, 13 of whom have Ph.D., M.D. or D.V.M. degrees. 47 full-time employees work in research and development and laboratory support services. No employees are covered by collective bargaining agreements. We consider our employee relations in general to be good.

Patents, Proprietary Rights and Licenses

We believe that proprietary protection of our inventions will be critical to our future business. We vigorously seek out intellectual property that we believe might be useful in connection with our products, and have an active program of protecting our intellectual property. We may also from time to time seek to acquire licenses to important externally developed technologies.

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We have exclusive or non-exclusive rights to a portfolio of patents and patent applications related to various stem and progenitor cells and methods of deriving and using them. These patents and patent applications relate to compositions of matter, methods of obtaining such cells, and methods for preparing, transplanting and utilizing these cells. We also own or have exclusive rights to exploit a number of patents that claim tools and techniques important to cell-based research. A number of these patents were acquired from SCS in April 2009. Additional patents were acquired from NsGene A/S, a Danish company, in February 2013. These patents claim GFAP+ Nestin+ precursor cells capable of differentiating into neurons. Among our significant U.S. patents covering stem and progenitor cells are:

Among our significant U.S. patents covering cell-based research tools and technologies are:

In October 2013, we acquired a portfolio of issued patents claiming compositions of human neural stem cells and their proliferation and use from NeuroSpheres Holdings, a Canadian holding company affiliated with the University of Calgary. Accordingly, of the patents identified above as being amongst our “significant” patents, eight are owned by us and five are exclusively licensed to us. The table below sets out the anticipated expiration

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dates of these patents absent the grant of any patent term extension, whether under the Hatch Waxman Act (Pub. L. 98-417) or otherwise:

We also rely upon trade secret protection for our proprietary information and know-how, and we take active measures to control access to this information. We believe that our know-how will also provide a significant competitive advantage.

Our policy is to require our employees, consultants and significant scientific collaborators and sponsored researchers to execute confidentiality agreements upon the commencement of any employment or consulting relationship with us. These agreements generally provide that all confidential information disclosed by us or developed during the course of the individual’s relationship with us is to be kept confidential and not disclosed to third parties except in specific circumstances. In the case of employees and consultants, the agreements generally provide that all inventions conceived by the individual in the course of rendering services to us will be our exclusive property.

Licenses Agreements

Since inception, we have entered into a number of license agreements with academic organizations and commercial entities, including NeuroSpheres, Ltd. (Neurospheres), ReNeuron Ltd. (ReNeuron), Stem Cell Therapeutics Corp. (SCT), genOway SA (genOway), and the University of Edinburgh, to either acquire or license out intellectual property rights. Under these license agreements, there are typically obligations of due diligence and the requirement to pay royalties on products that use patented technology licensed under these agreements. The license agreements with some of these institutions relate largely to stem or progenitor cells or to processes and methods for the isolation, identification, expansion, or culturing of stem or progenitor cells. Generally speaking, these license agreements will terminate upon expiration, revocation or invalidation of the licensed patents, unless governmental regulations require a shorter term. Typically, the licensee under each of these license agreements can terminate the agreement at any time upon notice. At this time, we do not believe the future success of our research and development efforts depend significantly on any particular license agreement or research collaboration. Nevertheless, we describe the more important license agreements below.

NeuroSpheres

In March 1994, we entered into a contract research and license agreement with NeuroSpheres, which was clarified in a license agreement dated as of April 1, 1997. Under the agreement as clarified, we obtained an exclusive patent license from NeuroSpheres in the field of transplantation, subject to a limited right of NeuroSpheres to purchase a nonexclusive license from us, which right was not exercised and has expired. We then developed additional intellectual property relating to the subject matter of the license. We entered into an additional license agreement with NeuroSpheres as of October 30, 2000, under which we obtained an exclusive license in the field of non-transplant uses, such as drug discovery. Together, our rights under these licenses were exclusive for all uses of the technology. All of the product-based royalty rates in the license agreement between the Company and NeuroSpheres were in the single digits. We made up-front payments to NeuroSpheres of 6,500 shares of our common stock in October 2000 and $50,000 in January 2001, and were required to make additional cash payments when milestones are achieved under the terms of the October 2000 agreement. In addition, in October 2000 we reimbursed NeuroSpheres for patent costs amounting to $341,000. Milestone payments, payable at various stages in the development of potential products, would total $500,000 for each

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product that is approved for market. In addition, beginning in 2004, annual payments of $50,000 became due, payable by the last day of the year and fully creditable against royalties due to NeuroSpheres under the October 2000 Agreement. In July 2008, we amended our 1997 and 2000 license agreements with NeuroSpheres. Six of the patents covered by the license agreements are the basis of our patent infringement suits against Neuralstem. Under the terms of the amendment, we agreed to pay all reasonable litigation costs, expenses and attorney’s fees incurred by NeuroSpheres in the declaratory judgment suit between us and Neuralstem. In return, we were entitled to off-set all litigation costs incurred in that suit against amounts that would otherwise be owed under the license agreements, such as annual maintenance fees, milestones and royalty payments.

In October, 2013, we acquired from NeuroSpheres the patent portfolio we licensed. As consideration for the patents, we issued 139,548 shares of unregistered common stock to NeuroSpheres. The acquisition relieves us from further milestone and royalty payments to NeuroSpheres., and all preexisting agreements were terminated.

University of Edinburgh

In January 2006, we entered into an exclusive, world-wide license agreement with the University of Edinburgh covering approximately twelve separate patent families in the stem cell field. Since then, the parties added some additional patent families and dropped some patent families which were not considered core to our business activities. Today, the license agreement patent families, including several that cover culture media and research technologies, one that covers purified populations of neural stem cells, some that cover cell reprogramming technologies, and one that covers the manipulation and use of embryonic stem cells for the derivation of research animal models, such as knock-out rats, with one or more missing genes. Under the license agreement, we have the exclusive right to commercialize the technologies in all fields. We have been paying royalties to the University of Edinburgh on the commercial sale of certain SC Proven products, and will pay royalties on all net sales of products covered by any of the intellectual property licensed under this agreement. All of the product-based royalty rates in the license agreement between the Company and the University of Edinburgh are in the single digits and there are no provisions under the University of Edinburgh license agreement for the payment of potential milestones by the Company.

ReNeuron

In July 2005, we entered into an agreement with ReNeuron under which we granted ReNeuron a license that allows ReNeuron to exploit its “c-mycER” conditionally immortalized adult human neural stem cell technology for therapy and other purposes. We received shares of ReNeuron common stock, as well as a cross-license to the exclusive use of ReNeuron’s technology for certain diseases and conditions, including lysosomal storage diseases, spinal cord injury, cerebral palsy, and multiple sclerosis. The agreement also provides for full settlement of any potential claims that either we or ReNeuron might have had against the other in connection with any putative infringement of certain of each party’s patent rights prior to the effective date of the agreement. As part of the agreement, we received in aggregate, approximately 10,097,000 ordinary shares of ReNeuron common stock, net of approximately 122,000 shares that were transferred to NeuroSpheres. Between 2007 and 2011, we sold our entire holdings of shares of ReNeuron common stock for aggregate net proceeds of approximately $3,743,000. As of June 30, 2011, we no longer hold any shares of ReNeuron.

Stem Cell Therapeutics

In August 2006, we entered into an agreement with Stem Cell Therapeutics, a Canadian corporation listed on the Toronto Stock Exchange, granting it a non-exclusive, royalty-bearing license to use several of our patents for treating specified diseases of the central nervous system; the grant does not include any rights to cell transplantation. SCT granted us a royalty-free non-exclusive license to certain of its patents for research and development and a royalty-bearing non-exclusive license for certain commercial purposes. SCT paid an up-front license fee; the license also provides for other payments including annual maintenance, milestones and royalties.

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genOway

In October 2008, we entered into a license agreement with genOway, a leading transgenics company located in France, in which we granted a non-exclusive sublicense to genOway for the use of Internal Ribosome Entry Site (IRES) technology. The IRES technology enables the dual expression of a protein of interest and a selectable marker, thereby enabling researchers to genetically modify any mammalian cell and monitor the activity of a particular gene of interest in living cells or tissues without blocking the normal function of the gene. The IRES technology is particularly important for evaluating the success of gene knock-outs or knock-ins in stem cells and for the successful creation of transgenic rodent disease models. The IRES technology has been used to develop hundreds of genetically modified models in the past decade, and the technology is now considered to be the reference technology for transgene expression in some key rodent animal models, such as humanized models, reporter model, and cell trafficking models. The IRES technology is covered by one of the patent families exclusively licensed to us by the University of Edinburgh, specifically U.S. Patents No. 7,005,299 and 6,150,169 and their foreign counterparts.

In March 2012, we agreed to amend the genOway license agreement to give genOway exclusive worldwide rights, including a right to grant sublicenses, under the IRES patent family in order to commercialize transgenic mice, and provide related services such as the genetic engineering of such mice. Under this exclusive license agreement, as amended, we received a six figure lump sum payment in lieu of annual maintenance fees, and will receive single digit royalties on licensed products and services.

Other Commercial Licenses

We have approximately thirteen other license agreements with commercial entities, which we entered into in the ordinary course of business to monetize certain of our patents. A number of these include sublicenses to certain patents exclusively licensed to us from either NeuroSpheres or the University of Edinburgh. Some of these are license agreements to commercialize cells. A number of these are license agreements to our research tools patents, such as the IRES and selectable marker technologies described above. We have an on-going licensing program at the Company with the goal of identifying likely infringers of our intellectual property rights in order to generate license revenues.

Scientific Advisory Board

Members of our Scientific Advisory Board provide us with strategic guidance primarily in regard to our therapeutic products research and development programs, as well as assistance in recruiting employees and collaborators. Each Scientific Advisory Board member has entered into a consulting agreement with us. These consulting agreements specify the compensation to be paid and require that all information about our products and technology be kept confidential. All of the Scientific Advisory Board members are employed by employers other than us and may have commitments to, or consulting or advising agreements with, other entities that limit their availability to us. The Scientific Advisory Board members have generally agreed, however, for so long as they serve as consultants to us, not to provide any services to any other entities that would conflict with the services the member provides to us. We are entitled to terminate the arrangements if we determine that there is such a conflict.

The following persons are members of our Scientific Advisory Board:

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Government Regulation

Our research and development activities and the future manufacturing and marketing of our potential therapeutic products are, and will continue to be, subject to regulation for safety and efficacy by numerous governmental authorities in the United States and other countries.

U.S. Regulations

In the United States, pharmaceuticals, biologicals and medical devices are subject to rigorous regulation by the U.S. Food and Drug Administration (FDA). The Federal Food, Drug and Cosmetic Act, the Public Health Service Act, applicable FDA regulations, and other federal and state statutes and regulations govern, among other things, the testing, manufacture, labeling, storage, export, record keeping, approval, marketing, advertising, and promotion of our potential products. Product development and approval within this regulatory framework takes a number of years and involves significant uncertainty combined with the expenditure of substantial resources. In addition, many jurisdictions, both federal and state, have restrictions on the use of fetal tissue.

FDA Marketing Approval

The steps required before our potential therapeutic products may be marketed in the United States include:

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FDA Manufacturing Requirements

Among the conditions for product licensure is the requirement that the prospective manufacturer’s quality control and manufacturing procedures conform to the FDA’s current good manufacturing practice (GMP) requirements. Even after a product’s licensure approval, its manufacturer must comply with GMP on a continuing basis, and what constitutes GMP may change as the state of the art of manufacturing changes. Domestic manufacturing facilities are subject to regular FDA inspections for GMP compliance, which are normally held at least every two years. Foreign manufacturing facilities are subject to periodic FDA inspections or inspections by the foreign regulatory authorities. Domestic manufacturing facilities may also be subject to inspection by foreign authorities.

Orphan Drug Act

The Orphan Drug Act provides incentives to drug manufacturers to develop and manufacture drugs for the treatment of diseases or conditions that affect fewer than 200,000 individuals in the United States. Orphan drug status can also be sought for treatments for diseases or conditions that affect more than 200,000 individuals in the United States if the sponsor does not realistically anticipate its product becoming profitable from sales in the United States. We may apply for orphan drug status for certain of our therapies. Under the Orphan Drug Act, a manufacturer of a designated orphan product can seek tax benefits, and the holder of the first FDA approval of a designated orphan product will be granted a seven-year period of marketing exclusivity in the United States for that product for the orphan indication. While the marketing exclusivity of an orphan drug would prevent other sponsors from obtaining approval of the same compound for the same indication, it would not prevent other compounds or products from being approved for the same use including, in some cases, slight variations on the originally designated orphan product.

FDA programs to expedite drug development for serious conditions

We may avail of various FDA programs that are intended to facilitate and expedite development and review of new drugs to address unmet medical need in the treatment of serious or life-threatening conditions.

Breakthrough therapy designation

This program is intended to expedite the development and review of drugs for serious or life-threatening conditions. The criteria for breakthrough therapy designation require preliminary clinical evidence that demonstrates the drug may have substantial improvement on at least one clinically significant endpoint over available therapy. A breakthrough therapy designation conveys all of the fast track program features as well as more intensive FDA guidance on an efficient drug development program.

Fast Track Designation

This program is intended to facilitate the development and expedite the review of drugs to treat serious conditions and fill an unmet medical need. Designation may be granted on the basis of preclinical data. A sponsor of a drug that receives fast track designation will typically have more frequent interactions with FDA

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during drug development. In addition, products that have been designated as fast track can submit portions of a marketing application before submitting the complete application, known as rolling review.

Accelerated Approval

This program can be used for speeding the development and approval of promising therapies that treat a serious or life-threatening condition and provide meaningful therapeutic benefit over available therapies. Accelerated approval allows approval of a drug that demonstrates an effect on a “surrogate endpoint” that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality (IMM) that is reasonably likely to predict an effect on IMM or other clinical benefit. The accelerated approval pathway is most often useful in settings in which the disease course is long and an extended period of time is required to measure the intended clinical benefit of a drug, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. Nevertheless, even after the drug enters the market, the sponsor may be required to conduct post-marketing trials to verify and describe the drug’s clinical benefit. If further trials fail to verify the predicted clinical benefit, the FDA may withdraw approval. A drug that has received a breakthrough therapy designation or a fast track designation can be eligible for the accelerated approval pathway, if the relevant criteria are met.

FDA Human Cell and Tissue Regulations

Our research and development is based on the use of human stem and progenitor cells. The FDA has initiated a risk-based approach to regulating Human Cells, Tissues, and Human Cellular and Tissue-based products (HCT/P) and has published current Good Tissue Practice (GTP) regulations. As part of this approach, the FDA has published final rules for registration of establishments that recover, process, store, label, package, or distribute HCT/P or that screen or test the donor of HCT/P, and for the listing of such products. In addition, the FDA has published rules for determining the suitability of donors of cells and tissue, the eligibility of the cells and tissues for clinical use and for current good tissue practice for manufacturers using them. We have adopted policies and procedures to comply with these regulations.

Other Regulations

In addition to safety regulations enforced by the FDA, we are also subject to regulations under the Occupational Safety and Health Act, the Environmental Protection Act, the Toxic Substances Control Act, and other present and potential future foreign, federal, state, and local regulations.

International Law

Outside the United States, we will be subject to regulations that govern the import of drug products from the United States or other manufacturing sites and foreign regulatory requirements governing human clinical trials and marketing approval for our products. The requirements governing the conduct of clinical trials, product licensing, pricing, and reimbursements vary widely from country to country. In particular, the European Union (EU) is revising its regulatory approach to biotechnology products, and representatives from the United States, Japan and the EU are in the process of harmonizing and making more uniform the regulations for the registration of pharmaceutical products in these three markets. This process increases uncertainty over regulatory requirements in our industry. Furthermore, human stem and progenitor cells may be regulated in the EU and other countries as transplant material or as a somatic cell therapy medicinal product, depending on the processing, indication and country.

Environment

We have made, and will continue to make, expenditures for environmental compliance and protection. Expenditures for compliance with environmental laws have not had, and are not expected to have, a material effect on our capital expenditures, results of operations or competitive position.

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Reimbursement and Health Care Cost Control

Reimbursement for the costs of treatments and products such as ours from government health administration authorities, private health insurers and others, both in the United States and abroad, is a key element in the success of new health care products. Significant uncertainty often exists as to the reimbursement status of newly approved health care products.

The revenue and profitability of some health care-related companies have been affected by the continuing efforts of governmental and third party payors to contain or reduce the cost of health care through various means. Payors are increasingly attempting to limit both coverage and the levels of reimbursement for new therapeutic products approved for marketing by the FDA, and are refusing, in some cases, to provide any coverage for uses of approved products for disease indications for which the FDA has not granted marketing approval. In certain foreign markets, pricing or profitability of prescription pharmaceuticals is subject to government control. In the United States, there have been a number of federal and state proposals to implement government control over health care costs.

The U.S. Patient Protection and Affordance Care Act and the Health Care and Education Reconciliation Act were signed into law in March 2010. A number of provisions of those laws require further rulemaking action by governmental agencies to implement. The laws change access to health care products and services and create new fees for the pharmaceutical and medical device industries. Future rulemaking could increase rebates, reduce prices or the rate of price increases for health care products and services, or require additional reporting and disclosure. The laws also include new authorization to the FDA to approve companies to market biosimilar products within the United States, although to date FDA rulemaking under this legislation has been limited. We cannot predict the timing or impact of any such future rulemaking on our business.

Competition

In most instances, the targeted indications for our initial products in development have no effective long-term therapies at this time. However, we do expect that our initial products will have to compete with a variety of therapeutic products and procedures. Other pharmaceutical and biotechnology companies currently offer a number of pharmaceutical products to treat lysosomal storage diseases, neurodegenerative and liver diseases, and other diseases for which our technologies may be applicable. Many pharmaceutical and biotechnology companies are investigating new drugs and therapeutic approaches for the same purposes, which may achieve new efficacy profiles, extend the therapeutic window for such products, alter the prognosis of these diseases, or prevent their onset. We believe that our products, when and if successfully developed, will compete with these products principally on the basis of improved and extended efficacy and safety and their overall economic benefit to the health care system. The market for therapeutic products that address degenerative diseases is large and competition is intense. Many companies have significant products approved or in development that could be competitive with our potential products. We expect competition to increase.

Competition for any stem and progenitor cell products that we may develop may be in the form of existing and new drugs, other forms of cell transplantation, ablative and simulative procedures, medical devices, and gene therapy. We believe that some of our competitors are also trying to develop stem and progenitor cell-based technologies. We may also face competition from companies that have filed patent applications relating to the use of genetically modified cells to treat disease, disorder or injury. In the event our therapies should require the use of such genetically modified cells, we may be required to seek licenses from these competitors in order to commercialize certain of our proposed products, and such licenses may not be granted.

If we develop products that receive regulatory approval, they would then have to compete for market acceptance and market share. For certain of our potential products, an important success factor will be the timing of market introduction of competitive products. This is a function of the relative speed with which we and our competitors can develop products, complete the clinical testing and approval processes, and supply commercial quantities of a product to market. These competitive products may also impact the timing of clinical testing and

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approval processes by limiting the number of clinical investigators and patients available to test our potential products.

We expect that all of these products will compete with our potential stem and progenitor cell-based products based on efficacy, safety, cost, and intellectual property positions. While we believe that these will be the primary competitive factors, other factors include, in certain instances, obtaining marketing exclusivity under the Orphan Drug Act, availability of supply, manufacturing, marketing and sales expertise and capability, and reimbursement coverage.

The research markets served by our tools and technologies are highly competitive, complex and dynamic. Technological advances and scientific discoveries have accelerated the pace of change in biological research, and stem cell technologies have been evolving particularly fast. In these markets we face a wide array of competitors, ranging from specialized companies with strengths in niche segments of the life science markets to large manufacturers offering a broad portfolio of products, tools and services. Many of these competitors have significant financial, operational, sales, and marketing resources, and experience in research and development. In some cases, these and other competitors are also our customers, distributors and suppliers. In addition, many of our products can be “home brewed” by customers following publicly available procedures and methodologies.

Reliable independent information on sales and market share of products produced by our competitors is not generally available. We believe, however, based on our own estimates, that no one company is so dominant that it prevents other companies from competing effectively. We compete mainly by focusing on specialty products, which are custom designed for use in stem cell-based research, where we believe our expertise, intellectual property and reputation give us competitive advantage. We believe that, in this particular market niche, our products and technologies offer customers specific advantages over those offered by our competitors. We compete by offering innovative, quality-controlled products, consistently made and designed to produce reproducible results. We tend to avoid head to head competition against entrenched competitors with commoditized products.

Available Information

The following information can be obtained free of charge through our website at http://www.stemcellsinc.com or by sending an e-mail message to irpr@stemcellsinc.com:

The public may read and copy any material we file with the SEC at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, DC, 20549. The public may obtain information on the operations of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an Internet site, http://www.sec.gov, which contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC.

This annual report on Form 10-K contains forward-looking statements that involve risks and uncertainties. Our business, operating results, financial performance, and share price may be materially adversely affected by a number of factors, including but not limited to the following risk factors, any one of which could cause actual

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results to vary materially from anticipated results or from those expressed in any forward-looking statements made by us in this annual report on Form 10-K or in other reports, press releases or other statements issued from time to time. Additional factors that may cause such a difference are set forth elsewhere in this annual report on Form 10-K. Forward-looking statements speak only as of the date of this report. We do not undertake any obligation to publicly update any forward-looking statements.

Risks Related to our Business

Any adverse development relating to our HuCNS-SC product candidate, such as a significant clinical trial failure, could substantially depress our stock price and prevent us from raising additional capital.

At present, our ability to progress as a company is significantly dependent on a single platform technology, our HuCNS-SC cells (purified human neural stem cells), and on early stage clinical trials. Any clinical, regulatory or other development that significantly delays or prevents us from completing any of our trials, any material safety issue or adverse side effect to any study participant in any of these trials, or the failure of these trials to show the results expected would likely depress our stock price significantly and could prevent us from raising the substantial additional capital we will need to further develop our cell technologies. Moreover, any material adverse occurrence in our first clinical trials could substantially impair our ability to initiate additional clinical trials to test our HuCNS-SC cells, whether in other potential indications or otherwise. This, in turn, could adversely impact our ability to raise additional capital and pursue our planned research and development efforts.

We have limited capital resources and we may not obtain the significant additional capital needed to sustain our research and development efforts.

We have limited liquidity and capital resources and must obtain significant additional capital resources in order to sustain our product development efforts, acquire businesses, technologies and intellectual property rights which may be important to our business, continue preclinical and clinical testing of our therapeutic products, pursue regulatory approvals, acquire capital equipment, laboratory and office facilities, establish production capabilities, maintain and enforce our intellectual property portfolio, and support our general and administrative expenses and other working capital requirements. We rely on cash reserves and proceeds from equity and debt offerings, proceeds from the transfer, license, lease, or sale of our intellectual property rights, equipment, facilities, or investments, and government grants and funding from collaborative arrangements, if obtainable, to fund our operations.

We intend to pursue opportunities for additional fundraising in the future through equity or debt financings, corporate alliances or combinations, grants or collaborative research arrangements, sales or dispositions of assets, or any combination of these. However, the source, timing and availability of any future fundraising will depend principally upon market conditions, and, more specifically, on progress in our research, preclinical and clinical development programs. Funding may not be available when needed — at all or on terms acceptable to us. While we actively manage our programs and resources in order to conserve cash between fundraising opportunities, our existing capital resources may not be sufficient to fund our operations beyond the next twelve months. Lack of necessary funds may require us, among other things, to delay, scale back or eliminate some or all of our research and product development programs, planned clinical trials, and/or our capital expenditures or to license our potential products or technologies to third parties. If we exhaust our cash reserves and are unable to realize adequate additional fundraising, we may be unable to meet operating obligations and be required to initiate bankruptcy proceedings or delay, scale back or eliminate some or all of our research and product development programs.

Our product development programs are based on novel technologies and are inherently risky.

We are subject to the risks of failure inherent in the development of products based on new technologies. The novel nature of these therapies creates significant challenges in regard to product development and optimization, manufacturing, government regulation, third party reimbursement, and market acceptance. For

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example, the pathway to regulatory approval for cell-based therapies, including our therapeutic product candidates, may be more complex and lengthy than the pathway for conventional drugs. These challenges may prevent us from developing and commercializing products on a timely or profitable basis or at all.

Our technologies are at early stages of discovery and development, and we may fail to develop any commercially acceptable or profitable products.

We have incurred significant operating losses and negative cash flows since inception. We have not achieved profitability and may not be able to realize sufficient revenue to achieve or sustain profitability in the future. We have yet to develop any therapeutic products that have been approved for marketing, and we do not expect to become profitable within the next several years, but rather expect to incur additional and increasing operating losses. Before commercializing any therapeutic product, we will need to obtain regulatory approval from the FDA or from equivalent foreign agencies after conducting extensive preclinical studies and clinical trials that demonstrate that the product candidate is safe and effective. Except for the Phase I NCL and Phase I PMD trials we completed, and our currently ongoing Phase I/II clinical trial in spinal cord injury and Phase I/II clinical trial in dry age-related macular degeneration, we have had no experience conducting human clinical trials. We expect that none of our cell-based therapeutic product candidates will be commercially available for several years, if at all.

While regulatory agencies in the United States, Switzerland and Canada have approved the clinical study of our cells in a total of four indications, there can be no assurance that any of our clinical trials will be completed or result in a successful outcome.

We may elect to delay or discontinue studies or clinical trials based on unfavorable results. Any product developed from, or based on, cell technologies may fail to:

In addition, our therapeutic products may cause undesirable side effects. Results of preclinical research in animals may not be indicative of future clinical results in humans.

Ultimately, if regulatory authorities do not approve our products or if we fail to maintain regulatory compliance, we would be unable to commercialize our products, and our business and results of operations would be harmed. Even if we do succeed in developing products, we will face many potential obstacles such as the need to develop or obtain manufacturing, marketing and distribution capabilities. Furthermore, because transplantation of cells is a new form of therapy, the marketplace may not accept any products we may develop.

Moreover, because our cell-based therapeutic products will be derived from tissue of individuals other than the patient (that is, they will be “non-self” or “allogeneic” transplant products), patients may require the use of immunosuppressive drugs. While immunosuppression is now standard in connection with allogeneic transplants of various kinds, such as heart or liver transplants, long-term maintenance on immunosuppressive drugs can result in complications such as infection, cancer, cardiovascular disease, and renal dysfunction. An immunosuppression regimen was used with our therapeutic product candidate in all our clinical trials to date.

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Delays in the commencement or completion of clinical testing of our current and potential product candidates could result in increased costs to us and delay our ability to generate revenues.

The commencement of clinical trials can be delayed for a variety of reasons, including delays in:

Even after commencement, the completion of clinical trials can be delayed or prevented for a number of reasons, such as:

In addition, clinical trials may be delayed due to insufficient patient enrollment, which is a function of many factors, including the size and nature of the relevant patient populations, the nature of the protocols, the proximity of patients to clinical sites, the availability of effective treatments for the relevant diseases, clinical testing alternatives available to patients interested in enrolling in our studies, and the eligibility criteria for our clinical trials. Delays in clinical testing of our product candidate could prevent or delay us from obtaining the additional evidence of clinical efficacy we will need for the approval for our product candidate in any indication.

Acquisitions of companies, businesses or technologies may substantially dilute our stockholders and increase our operating losses.

We may make acquisitions of businesses, technologies or intellectual property rights or otherwise modify our business model in ways we believe to be necessary, useful or complementary to our current business. For example, in April 2009, we acquired substantially all of the operating assets and liabilities of Stem Cell Sciences

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Plc (SCS). Any such acquisition or change in business activities may require assimilation of the operations, products or product candidates and personnel of the acquired business and the training and integration of its employees, and could substantially increase our operating costs, without any offsetting increase in revenue. Acquisitions may not provide the intended technological, scientific or business benefits and could disrupt our operations and divert our limited resources and management’s attention from our current operations, which could harm our existing product development efforts. We would likely issue equity securities to pay for any other future acquisitions. The issuance of equity securities for an acquisition could be substantially dilutive to our stockholders. Any investment made in, or funds advanced to, a potential acquisition target could also significantly adversely affect our results of operation and could further reduce our limited capital resources. Any acquisition or action taken in anticipation of a potential acquisition or other change in business activities could substantially depress the price of our stock. In addition, our results of operations may suffer because of acquisition-related costs or the post-acquisition costs of funding the development of an acquired technology or product candidates or operation of the acquired business, or due to amortization or impairment costs for acquired goodwill and other intangible assets. In December 2011, for example, we determined that the intangible in-process research and development (IPR&D) asset related to the assays technology was impaired. In part because of management’s decision to focus on our therapeutic product development programs and not to allocate time and resources to the assays program, we determined that we could not predict the future cash flows from this asset and that the approximately $655,000 carrying value of the asset should be written-off in full.

We have payment obligations resulting from real property owned by us in Rhode Island, which diverts funding from our cell-based therapeutics research and development and enabling cell technologies programs.

We are obligated to make debt service payments and payments for operating costs for our former encapsulated cell therapy pilot manufacturing facility in Rhode Island, which we own. As of December 31, 2013, we have in aggregate, remaining principal and interest payments of approximately $137,000, which we are obligated to pay in full by July 2014. In addition, we currently have operating expenses of approximately $10,000 per month. We are not actively seeking subtenants, and we are actively seeking to dispose of our interests in this facility.

We may be unable to obtain partners to support our product development efforts when needed to commercialize our technologies.

Equity and debt financings alone may not be sufficient to fund the cost of developing our cell technologies, and we may need to rely on partnering or other arrangements to provide financial support for our product development efforts. In addition, in order to successfully develop and commercialize our technologies, we may need to enter into various arrangements with corporate sponsors, pharmaceutical companies, universities, research groups, and others. With the exception of our distribution agreements with Millipore Corporation, we have no such agreements. While we have engaged, and expect to continue to engage, in discussions regarding such arrangements, we may fail to obtain any such agreement on terms acceptable to us. Even if we enter into such arrangements, we may not be able to satisfy our obligations under them or renew or replace them after their original terms expire. Furthermore, these arrangements may require us to grant rights to third parties, such as exclusive marketing rights to one or more products, may require us to issue securities to our collaborators and may contain other terms that are burdensome to us or result in a decrease in our stock price.

If we are unable to protect our patents and proprietary rights, our business, financial condition and results of operations may be materially harmed.

We either own or exclusively license a number of patents and pending patent applications related to various stem and progenitor cells, including human neural stem cell cultures, as well as methods of deriving and using them. We also own or exclusively license a number of patents and patent applications related to certain mammalian pluripotent and multipotent stem cells, cellular reprogramming, genetic manipulation of stem cells,

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the creation of genetically engineered animals used for research, technologies that facilitate the identification and isolation of specific stem cell types, and media formulations for the culture of stem cells. The process of obtaining patent protection for products such as those we propose to develop is highly uncertain and involves complex and continually evolving factual, legal and occasionally ethical questions. The governmental authorities that consider patent applications can deny or significantly reduce the patent coverage requested in an application either before or after issuing the patent and procedures exist in all relevant geographies for third parties to challenge even issued patents. In addition, changes to the laws protecting intellectual property rights could adversely impact the perceived or actual value of our Company. Consequently, we do not know whether any of our pending applications will result in the issuance of patents, whether any of our issued patents will be invalidated or restricted, whether any existing or future patents will provide sufficient protection or significant commercial advantage, or whether others will circumvent or invalidate these patents, whether or not lawfully. In addition, our patents may not afford us adequate protection from competing products. Moreover, because patents issue for a limited term, our patents may expire before we can commercialize a product covered by the issued patent claims or before we can utilize the patents profitably. Some of our most important patents begin to expire in 2015.

If we learn of third parties who infringe our patent rights, we may decide to initiate legal proceedings to enforce these rights. In 2006, for example, we filed suit against Neuralstem, Inc. for patent infringement. Patent litigation, including the pending litigation to which we are a party, is inherently unpredictable and highly risky and may result in unanticipated challenges to the validity or enforceability of our intellectual property, antitrust claims or other claims against us, which could result in the loss of these intellectual property rights. Litigation proceedings can be very time-consuming for management and are also very costly and the parties we bring actions against may have significantly greater financial resources than our own. We may not prevail in these proceedings and if we do not prevail we could be liable for damages as well as the costs and attorney fees of our opponents.

Proprietary trade secrets and unpatented know-how are also important to our research and development activities. We cannot be certain that others will not independently develop the same or similar technologies on their own or gain access to our trade secrets or disclose such technology or that we will be able to meaningfully protect our trade secrets and unpatented know-how. We require our employees, consultants and significant scientific collaborators and sponsored researchers to execute confidentiality agreements upon the commencement of an employment or consulting relationship with us. These agreements may, however, fail to provide meaningful protection or adequate remedies for us in the event of unauthorized use, transfer or disclosure of such information or technology.

If we are unable to obtain necessary licenses to third-party patents and other rights, we may not be able to commercially develop our expected products.

A number of pharmaceutical, biotechnology and other companies, universities and research institutions have filed patent applications or have received patents relating to cell therapy, stem and progenitor cells and other technologies potentially relevant to, or necessary for, our expected products. We cannot predict which, if any, of these applications will issue as patents or how many of these issued patents will be found valid and enforceable. There may also be existing issued patents which we are currently unaware of which would be infringed by the commercialization of one or more of our product candidates. If so, we may be prevented from commercializing these products unless the third party is willing to grant a license to us. We may be unable to obtain licenses to the relevant patents at a reasonable cost, if at all, and may also be unable to develop or obtain alternative non-infringing technology. If we are unable to obtain such licenses or develop non-infringing technology at a reasonable cost, our business could be significantly harmed. Also, any infringement lawsuits commenced against us may result in significant costs, divert our management’s attention and result in an award against us for substantial damages, or potentially prevent us from continuing certain operations.

We are aware of intellectual property rights held by third parties that relate to products or technologies we are developing. For example, some aspects of our cell-based therapeutic product candidates involve the use of

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growth factors, antibodies and other reagents that may, in certain cases, be the subject of third party rights. Before we commercialize any product using these growth factors, antibodies or reagents, we may need to obtain license rights from third parties or use alternative growth factors, antibodies and reagents that are not then the subject of third party patent rights. We currently believe that the commercialization of our products as currently planned will not infringe these third party rights, or, alternatively, that we will be able to obtain necessary licenses or otherwise use alternative non-infringing technology. However, third parties may nonetheless bring suit against us claiming infringement. If we are unable to prove that our technology does not infringe their patents, or if we are unable to obtain necessary licenses or otherwise use alternative non-infringing technology, we may not be able to commercialize any products.

We have obtained rights from companies, universities and research institutions to technologies, processes and compounds that we believe may be important to the development of our products. These licensors, however, may cancel our licenses or convert them to non-exclusive licenses if we fail to use the relevant technology or otherwise breach these agreements. Loss of these licenses could expose us to the risk that our technology infringes the rights of third parties. We can give no assurance that any of these licenses will provide effective protection against our competitors.

We compete with companies that have significant advantages over us.

The market for therapeutic products to treat diseases of, or injuries to, the central nervous system (CNS) is large and competition is intense. The majority of the products currently on the market or in development are small molecule pharmaceutical compounds, and many pharmaceutical companies have made significant commitments to the CNS field. We believe cellular therapies, if proven safe and effective, will have unique properties that will make them desirable over small molecule drugs, none of which currently replace damaged tissue. However, any cell-based therapeutic to treat diseases of, or injuries to, the CNS is likely to face intense competition from small molecules, biologics, as well as medical devices. We expect to compete with a host of companies, some of which are privately owned and some of which have resources far greater than ours.

The life science and research markets are each highly competitive. Most of our competitors have greater financial resources than we do, making them better equipped to license technologies and intellectual property from third parties or to fund research and development, manufacturing and marketing efforts. Our competitors can be expected to continue to improve the design and performance of their products and to introduce new products with competitive price and performance characteristics.

The research market is heavily dependent on government funding, and changes in government funding can adversely affect revenues for our tools and technologies products.

Our customers include researchers at academic institutions, pharmaceutical and biotechnology companies and government laboratories, all of whom fund much of their stem cell research using government monies, such as grants. A number of these customers, for example, are dependent for their funding upon grants from U.S. government agencies, such as the U.S. National Institutes of Health (NIH) and agencies in other countries. The level of government funding of research and development is unpredictable. Research and development spending of our customers can fluctuate based on spending priorities and general economic conditions. There have been instances when NIH grants have been frozen or otherwise unavailable for extended periods. The availability of governmental research funding may also continue to be adversely affected by current economic instability. Any reduction or delay in governmental funding could cause our customers to delay or forego purchases or reallocate their budgets in a manner adverse to us, in which case our anticipated revenues could be materially lower.

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Development of our technologies is subject to, and restricted by, extensive government regulation, which could impede our business.

Our research and development efforts, as well as any ongoing or future clinical trials, and the manufacturing and marketing of any products we may develop, will be subject to, and restricted by, extensive regulation by governmental authorities in the United States and other countries. The process of obtaining FDA and other necessary regulatory approvals for human therapeutics is lengthy, expensive and uncertain. FDA and other legal and regulatory requirements applicable to the development and manufacture of the cells required for our preclinical and clinical products could substantially delay or prevent us from producing the cells needed to initiate additional clinical trials. We or our collaborators may fail to obtain the necessary approvals to commence or continue clinical testing or to manufacture or market our potential products in reasonable time frames, if at all. In addition, the U.S. Congress and other legislative bodies may enact regulatory reforms or restrictions on the development of new therapies that could adversely affect the regulatory environment in which we operate or the development of any products we may develop.

We base our research and development on the use of human stem and progenitor cells obtained from human tissue, including fetal tissue. The U.S. federal and state governments and other jurisdictions impose restrictions on the acquisition and use of fetal tissue, including those incorporated in federal Good Tissue Practice, or GTP, regulations. These regulatory and other constraints could prevent us from obtaining cells and other components of our products in the quantity or quality needed for their development or commercialization of both therapeutic products and certain of our enabling cell technologies. These restrictions change from time to time and may become more onerous. Additionally, we may not be able to identify or develop reliable sources for the cells necessary for our potential products — that is, sources that follow all state and federal laws and guidelines for cell procurement. Certain components used to manufacture our stem and progenitor cell product candidates will need to be manufactured in compliance with the FDA’s Good Manufacturing Practices, or GMP. Accordingly, we will need to enter into supply agreements with companies that manufacture these components to GMP standards.

Noncompliance with applicable requirements both before and after product marketing approval, if any, can subject us, our third party suppliers and manufacturers, and our other collaborators to administrative and judicial sanctions, such as, among other things, warning letters, fines and other monetary payments, recall or seizure of products, criminal proceedings, suspension or withdrawal of regulatory approvals, interruption or cessation of clinical trials, total or partial suspension of production or distribution, injunctions, limitations on or the elimination of claims we can make for our products, and refusal of the government to enter into supply contracts or fund research, or delay in approving or refusal to approve new drug applications.

We are dependent on the services of key personnel.

We are highly dependent on the principal members of our management, operations, and scientific staff, and on some of our outside consultants. Although we have entered into employment agreements with some of these individuals, they may terminate their agreements at any time. In addition, our operations are dependent upon our ability to attract and retain additional qualified scientific and management personnel. We may not be able to attract and retain the personnel we need on acceptable terms given the competition for experienced personnel among pharmaceutical, biotechnology and health care companies, universities and research institutions.

Our activities involve hazardous materials and experimental animal testing; improper handling of these animals and materials by our employees or agents could expose us to significant legal and financial penalties.

Our research and development activities involve the controlled use of test animals as well as hazardous chemicals and potentially hazardous biological materials such as human tissue. Their use subjects us to environmental and safety laws and regulations such as those governing laboratory procedures, exposure to

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blood-borne pathogens, use of laboratory animals, and the handling of biohazardous materials. Compliance with current or future laws and regulations may be expensive and the cost of compliance could adversely affect us.

Although we believe that our safety procedures for using, handling, storing, and disposing of hazardous and potentially hazardous materials comply with the standards prescribed by applicable state, federal and international law, the risk of accidental contamination or injury from these materials cannot be eliminated. In the event of such an accident or of any violation of these or future laws and regulations, state or federal authorities could curtail our use of these materials; we could be liable for any civil damages that result, the cost of which could be substantial; and we could be subjected to substantial fines or penalties. In addition, any failure by us to control the use, disposal, removal, or storage, or to adequately restrict the discharge, or to assist in the cleanup, of hazardous chemicals or hazardous, infectious or toxic substances could subject us to significant liability. Any such liability could exceed our resources and could have a material adverse effect on our business, financial condition and results of operations. Moreover, an accident could damage our research and manufacturing facilities and operations and result in serious adverse effects on our business.

Natural disasters and violent acts of public protest may cause damage or disruption to us and our employees, facilities, information systems, vendors, suppliers, and customers.

Our operations are concentrated in Northern California. The western United States has experienced a number of earthquakes, wildfires, flooding, landslides, and other natural disasters in recent years. These occurrences could damage or destroy our facilities which may result in interruptions to our business and losses that exceed our insurance coverage. In addition, we know that certain individuals are strenuously opposed to certain types of medical research, including animal testing and embryonic stem cell research engaged in by both us and many of our customers. Acts of both legal and illegal public protest, including picketing and bioterrorism, could affect the markets in which we operate and our business operations. Any of these events could cause a decrease in our actual and anticipated revenue, earnings, and cash flows.

The development, manufacturing and commercialization of cell-based therapeutic products expose us to product liability claims, which could lead to substantial liability.

By developing and, ultimately, commercializing therapeutic products, we are exposed to the risk of product liability claims. Product liability claims against us could result in substantial litigation costs and damage awards against us. We have obtained liability insurance that covers our clinical trials, and we will need to increase our insurance coverage if and when we begin commercializing products. We may not be able to obtain insurance on acceptable terms, if at all, and the policy limits on our insurance policies may be insufficient to cover our liability.

The manufacture of cell-based therapeutic products is novel, highly regulated, critical to our business, and dependent upon specialized key materials.

The manufacture of cell-based and related products is complicated and difficult, dependent upon substantial know-how and subject to the need for continual process improvements to be competitive. Our manufacturing experience is limited and the technologies are comparatively new. In addition, our ability to scale-up manufacturing to satisfy the various requirements of our planned clinical trials, such as GTP, GMP and release testing requirements, is uncertain. Manufacturing disruptions may occur and despite efforts to regulate and control all aspects of manufacturing, the potential for human or system failure remains. Manufacturing irregularities or lapses in quality control could have a serious adverse effect on our reputation and business, which could cause a significant loss of stockholder value. Many of the materials that we use to prepare our cell-based and related products are highly specialized, complex and available from only a limited number of suppliers or derived from a biological origin. At present, some of our material requirements are single sourced, and the loss of one or more of these sources may adversely affect our business if we are unable to obtain alternatives or alternative sources at all or upon terms that are acceptable to us.

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Because health care insurers and other organizations may not pay for our products or may impose limits on reimbursements, our ability to become profitable could be adversely affected.

In both domestic and foreign markets, sales of potential therapeutic products are likely to depend in part upon the availability and amounts of reimbursement from third-party health care payor organizations, including government agencies, private health care insurers and other health care payors, such as health maintenance organizations and self-insured employee plans. There is considerable pressure to reduce the cost of therapeutic products. Government and other third party payors are increasingly attempting to contain health care costs by limiting both coverage and the level of reimbursement for new therapeutic products and by refusing, in some cases, to provide any coverage for uses of approved products for disease indications for which the FDA or other relevant authority has not granted marketing approval. Moreover, in some cases, government and other third party payors have refused to provide reimbursement for uses of approved products for disease indications for which the FDA or other relevant authority has granted marketing approval. Significant uncertainty exists as to the reimbursement status of newly approved health care products or novel therapies such as ours. Even if we obtain regulatory approval to market our products, we can give no assurance that reimbursement will be provided by such payors at all or without substantial delay or, if such reimbursement is provided, that the approved reimbursement amounts will be sufficient to enable us to sell products we develop on a profitable basis. Changes in reimbursement policies could also adversely affect the willingness of pharmaceutical companies to collaborate with us on the development of our cellular technologies. In certain foreign markets, pricing or profitability of prescription pharmaceuticals is subject to government control. We also expect that there will continue to be a number of federal and state proposals to implement government control over health care costs. Efforts to change regulatory and reimbursement standards are likely to continue in future legislative sessions. We do not know what legislative proposals federal or state governments will adopt or what actions federal, state or private payors for health care goods and services may take in response to such proposals or legislation. We cannot predict the effect of government control and health care reimbursement practices on our business.

Ethical and other concerns surrounding the use of stem or progenitor-based cell therapy may negatively affect regulatory approval or public perception of our product candidates, which could reduce demand for our products or depress our stock price.

The use of stem cells for research and therapy has been the subject of considerable public debate, with many people voicing ethical, legal and social concerns. Although these concerns have mainly been directed to the use of embryonic stem cells, which we are not presently pursuing for therapeutic use, the distinction between embryonic and non-embryonic stem cells is frequently overlooked; moreover, our use of human stem or progenitor cells from fetal sources might raise these or similar concerns. In addition, we are continuing the development of embryonic stem cells and iPS cells as potential research tools. Negative public attitudes toward stem cell therapy could result in greater governmental regulation of stem cell therapies, which could harm our business. The use of these cells could give rise to ethical and social commentary adverse to us, which could harm the market price of our common stock. Additional government-imposed restrictions on the use of embryos or human embryonic stem cells in research and development could also cause an adverse effect on us by harming our ability to establish important partnerships or collaborations, delaying or preventing the development of certain non-therapeutic products, and causing a decrease in the price of our stock or by otherwise making it more difficult for us to raise additional capital. For example, concerns regarding such possible regulation could impact our ability to attract collaborators and investors. Also, existing regulatory constraints on the use of embryonic stem cells may in the future be extended to use of fetal stem cells, and these constraints might prohibit or restrict us from conducting research or from commercializing products. Similarly, concerns and moral objections to embryonic and fetal-tissue derived technologies could delay or prevent us from patenting or enforcing our patents in certain geographies. Also, existing and potential government regulation of embryonic tissue may lead researchers to leave the field of stem cell research or the country altogether, in order to assure that their careers will not be impeded by restrictions on their work. Similarly, these factors may induce graduate students to choose other fields less vulnerable to changes in regulatory oversight, thus exacerbating the risk that we may not be able to attract and retain the scientific personnel we need in face of the competition among pharmaceutical,

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biotechnology and health care companies, universities and research institutions for what may become a shrinking class of qualified individuals.

Our corporate documents and Delaware law contain provisions that could make it difficult for us to be acquired in a transaction that might be beneficial to our stockholders.

Our board of directors has the authority to issue shares of preferred stock and to fix the rights, preferences, privileges, and restrictions of these shares without stockholder approval. These provisions in our corporate documents, along with certain provisions under Delaware law, may make it more difficult for a third party to acquire us or discourage a third party from attempting to acquire us, even if the acquisition might be beneficial to our stockholders.

Risks Related to Our Stock

Our stock price has been, and will likely continue to be, highly volatile, which may negatively affect our ability to obtain additional financing in the future.

The market price per share of our common stock has been and is likely to continue to be highly volatile due to the risks and uncertainties described in this section of this Annual Report on Form 10-K, as well as other factors, including:

Over the two-year period ended December 31, 2013, the trading price of our common stock as reported on NASDAQ ranged from a high of $2.66 to a low of $0.54 per share. As a result of this volatility, an investment in our stock is subject to substantial risk. Furthermore, the volatility of our stock price could negatively impact our ability to raise capital or acquire businesses or technologies.

Our stock could be delisted from the NASDAQ Capital Market, which could affect our stock’s market price and liquidity.

Our listing on the NASDAQ Capital Market is contingent upon meeting all the continued listing requirements of the NASDAQ Capital Market which include maintaining a minimum bid price of not less than $1.00 per share and a minimum of $2.5 million in stockholders’ equity. Our price per share and stockholders’ equity at December 31, 2013 was $1.23 and $15.0 million, respectively. If our common stock is delisted from the NASDAQ Capital Market, our ability to raise capital in the future may be limited. Delisting could also result in less liquidity for our stockholders and a lower stock price.

We are contractually obligated to issue shares in the future, diluting the interest of current stockholders.

As of December 31, 2013, there were outstanding warrants to purchase 16,267,659 shares of our common stock, at a weighted average exercise price of $3.27 per share, outstanding options to purchase 428,258 shares of

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our common stock, at a weighted average exercise price of $19.97 per share, and outstanding restricted stock units for 3,326,282 shares of our common stock. We expect to issue additional options and restricted stock units to purchase shares of our common stock to compensate employees, consultants and directors, and may issue additional shares to raise capital, to acquire other companies or technologies, to pay for services, or for other corporate purposes. Any such issuances will have the effect of diluting the interest of current stockholders.

None

In December 2010, we entered into a commercial lease agreement with BMR-Gateway Boulevard LLC (BMR), as landlord, for approximately 43,000 square feet of office and research space at BMR’s Pacific Research Center in Newark, California. The initial term of the lease is approximately eleven and one-half years. We will pay approximately $17,869,000 in aggregate as rent over the term of the lease to BMR. As part of the lease, BMR agreed to provide various financial allowances so that we can build initial and future laboratories, offices and other improvements, subject to customary terms and conditions relating to landlord-funded tenant improvements.

In September 2010, we entered into a two-year sublease agreement with Caliper Life Sciences, Inc., for office and research space in a facility located in Mountain View, California. In June 2012, the sublease term was extended to September 30, 2013. We paid approximately $1,081,000 in aggregate as rent over the term of the lease. The lease terminated in accordance with its terms on September 30, 2013.

In March 2013, we entered into a commercial lease agreement with Prologis, L.P. (Prologis), as landlord, for office and research space in Sunnyvale, California. The facility is for operations that support our clinical development activities. The initial term of the lease is ten years and includes escalating rent payments which we recognize as lease operating expense on a straight-line basis. We will pay approximately $3,497,000 in aggregate rent over the term of the lease. As part of the lease, Prologis has agreed to provide us financial allowances to build initial tenant improvements, subject to customary terms and conditions relating to landlord-funded tenant improvements.

We entered into a fifteen-year lease agreement for a scientific and administrative facility (SAF) in Rhode Island in connection with a sale and leaseback arrangement in 1997. The lease term expired on June 30, 2013. For the year 2013, we paid approximately $1,165,000 in operating lease payments and operating expenses net of sub-tenant income.

We own a 21,000 square-foot pilot manufacturing facility and a 3,000 square-foot cell processing facility in Rhode Island financed by bonds issued by the Rhode Island Industrial Facilities Corporation. As of December 31, 2013, we have in aggregate, remaining principal and interest payments of approximately $137,000, which we are obligated to pay in full by July 2014. We are actively seeking to dispose our remaining interests in these properties.

In January 2011, we amended the existing lease agreements of our wholly-owned subsidiary, Stem Cell Sciences (U.K.) Ltd, effectively reducing our leased office and lab space. The lease by its terms was extended to September 30, 2013. In October 2013, we signed a new three-year lease agreement for the leased space and expect to pay rent of approximately GBP 53,000 per annum. StemCells, Inc. is the guarantor of Stem Cell Sciences (U.K.) Ltd’s obligations under the existing lease. The lease gives SCS an option for early termination of the lease agreement.

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In July 2006, we filed suit against Neuralstem, Inc. in the Federal District Court for the District of Maryland, alleging that Neuralstem’s activities violate claims in four of the patents we exclusively licensed at the time from NeuroSpheres, specifically U.S. Patent No. 6,294,346 (claiming the use of human neural stem cells for drug screening), U.S. Patent No. 7,101,709 (claiming the use of human neural stem cells for screening biological agents), U.S. Patent No. 5,851,832 (claiming methods for proliferating human neural stem cells), and U.S. Patent No. 6,497,872 (claiming methods for transplanting human neural stem cells). In May 2008, we filed a second patent infringement suit against Neuralstem and its two founders, Karl Johe and Richard Garr. In this suit, which we filed in the Federal District Court for the Northern District of California, we allege that Neuralstem’s activities infringe claims in two patents we exclusively licensed at the time from NeuroSpheres, specifically U.S. Patent No. 7,361,505 (claiming composition of matter of human neural stem cells derived from any source material) and U.S. Patent No. 7,115,418 (claiming methods for proliferating human neural stem cells). In addition, we allege various state law causes of action against Neuralstem arising out of its repeated derogatory statements to the public about our patent portfolio. Also in May 2008, Neuralstem filed suit against us and NeuroSpheres in the Federal District Court for the District of Maryland seeking a declaratory judgment that the ‘505 and ‘418 patents are either invalid or are not infringed by Neuralstem and that Neuralstem has not violated California state law. In August 2008, the California court transferred our lawsuit against Neuralstem to Maryland for resolution on the merits. In July 2009, the Maryland District Court granted our motion to consolidate these two cases with the litigation we initiated against Neuralstem in 2006. Discovery is ongoing in these cases.

In addition to the actions described above, in April 2008, we filed an opposition to Neuralstem’s European Patent No. 0 915 968 (methods of isolating, propagating and differentiating CNS stem cells), because the claimed invention is believed by us to be unpatentable over prior art, including the patents we acquired from NeuroSpheres. In December 2010, the European Patent Office ruled that all composition claims in Neuralstem’s ‘968 European patent were invalid and unpatentable over prior art. Neuralstem has appealed this decision.

In October 2013, we acquired from NeuroSpheres a patent portfolio consisting of the patents we licensed from NeuroSpheres on an exclusive worldwide basis, including the six patents that are the subject of our patent infringement litigation against Neuralstem. As consideration for the patents, we issued 139,548 shares of unregistered common stock to NeuroSpheres. In connection with the patent acquisition, all preexisting agreements were terminated. The acquisition relieves us from further milestone and royalty payments to NeuroSpheres.

Not applicable.

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PART II

Market price and dividend information

Our stock is traded on the NASDAQ Capital Market under the symbol STEM. The quarterly ranges of high and low bid prices per share for the last two fiscal years as reported by NASDAQ are shown below:

No cash dividends have been declared on our common stock since our inception.

PERFORMANCE GRAPH

We show below the cumulative total return to our stockholders during the period from December 31, 2008 through December 31, 2013⁽¹⁾ in comparison to the cumulative return on the Standard & Poor’s 500 Index and the Amex Biotechnology Index during that same period.

The stock price performance shown on the graph below is not necessarily indicative of future stock price performance.

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The information under “Performance Graph” is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference in any Company filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this 10-K and irrespective of any general incorporation language in those filings.

As of March 3, 2014, there were approximately 251 holders of record of our common stock and the closing price of our common stock on the NASDAQ Capital Market was $1.47 per share.

The number of record holders is based upon the actual number of holders registered on the books of our transfer agent at such date and does not include holders of shares in “street names” or persons, partnerships, associations, corporations, or other entities identified in security position listings maintained by depository trust companies.

In October, 2013, we acquired from NeuroSpheres a patent portfolio we licensed on an exclusive worldwide basis, including the six patents that are the subject of our patent infringement litigation against Neuralstem. As consideration for the patents, we issued 139,548 shares of unregistered common stock to NeuroSpheres. In connection with the patent acquisition, all preexisting agreements were terminated. The acquisition relieves us from further milestone and royalty payments to NeuroSpheres.

In September 2012, pursuant to Regulation S of the Securities Act of 1933, we issued 24,753 shares of restricted common stock under the terms of an agreement with a developer of biological materials in return for certain product rights including an exclusive right of first offer to commercialize the developer’s products as may be developed on or before April 18, 2017.

We did not issue unregistered securities in 2011.

Equity Compensation Plan Information

The following table provides certain information with respect to all of our equity compensation plans in effect as of December 31, 2013.

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The following selected financial and operating data are derived from our audited consolidated financial statements. The selected financial and operating data should be read in conjunction with “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operation” and the consolidated financial statements and notes thereto contained elsewhere in this Form 10-K.

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This report contains forward looking statements that involve substantial risks and uncertainties. Such statements include, without limitation, all statements as to expectation or belief and statements as to our future results of operations; the progress of our research, product development and clinical programs; the need for, and timing of, additional capital and capital expenditures; partnering prospects; costs of manufacture of products; the protection of, and the need for, additional intellectual property rights; effects of regulations; the need for additional facilities; and potential market opportunities. Our actual results may vary materially from those contained in such forward-looking statements because of risks to which we are subject, including the fact that additional trials will be required to confirm the safety and demonstrate the efficacy of our HuCNS-SC cells for the treatment of any disease or disorder; uncertainty as to whether the U.S. Food and Drug Administration (FDA), Swissmedic, Health Canada or other regulatory authorities will permit us to proceed with clinical testing of proposed products despite the novel and unproven nature of our technologies; the risk that our clinical trials or studies could be substantially delayed beyond their expected dates or cause us to incur substantial unanticipated costs; uncertainties in our ability to obtain the capital resources needed to continue our current research and development operations and to conduct the research, preclinical development and clinical trials necessary for regulatory approvals; the uncertainty regarding our ability to obtain a corporate partner or partners, if needed, to support the development and commercialization of our potential cell-based therapeutics products; the uncertainty regarding the outcome of our clinical trials or studies we may conduct in the future; the uncertainty regarding the validity and enforceability of our issued patents; the risk that we may not be able to manufacture additional master and working cell banks when needed; the uncertainty whether any products that may be generated in our cell-based therapeutics programs will prove clinically safe and effective; the uncertainty whether we will achieve significant revenue from product sales or become profitable; obsolescence of our technologies; competition from third parties; intellectual property rights of third parties; litigation risks; and other risks to which we are subject. Forward-looking statements speak only as of the date of this report. We do not undertake any obligation to publicly update any forward-looking statements. All forward-looking statements attributable to us or to persons acting on our behalf are expressly qualified in their entirety by the cautionary statements and risk factors set forth in “Risk Factors” in Part I, Item 1A of this Form 10-K.

Overview

The Company

We are engaged in researching, developing, and commercializing cell-based therapeutics and enabling tools and technologies for stem cell-based research and drug discovery and development. Our research and development (R&D) programs are primarily focused on identifying and developing potential cell-based therapeutics which can either restore or support organ function. In particular, since we relocated our operations to California in 1999, our R&D efforts have been directed at refining our methods for identifying, isolating, culturing, and purifying the human neural stem cell and developing this cell as potential cell-based therapeutics for the central nervous system (CNS). Our HuCNS-SC^® cells (purified human neural stem cells) are currently in clinical development for several indications — chronic spinal cord injury, dry age-related macular degeneration (AMD) and Pelizeaus-Merzbacher disease (PMD), which is a myelination disorder in the brain. We are also conducting preclinical research to evaluate HuCNS-SC cells in Alzheimer’s disease.

In October 2012, we published in Science Translational Medicine, a peer-reviewed journal, the data from our four-patient Phase I clinical trial in PMD, which showed preliminary evidence of durable and progressive donor-derived myelination in all four patients. In addition, there were measurable gains in neurological function in three of the four patients, with the fourth patient clinically stable. We are conducting a Phase I/II clinical trial for the treatment of chronic spinal cord injury, which represents the first time that neural stem cells have been transplanted as a potential therapeutic agent for spinal cord injury. To accelerate patient enrollment, we have expanded this trial from a single-site, single-country study to a multi-site, multi-country program. This trial is being conducted in Switzerland, Canada, and the United States. Data from the first three patients demonstrated a

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favorable safety profile and multi-segment gains in sensory function in two of the three patients 12 months after transplantation of HuCNS-SC cells compared to pre-transplant baselines; the third patient remained stable. As of February 2014, a total of eleven patients have been dosed with our HuCNS-SC cells in this trial and we expect to complete enrollment of the final patient in the first quarter of 2014. We plan to initiate by the middle of 2014, a controlled Phase II efficacy study to further investigate our HuCNS-SC cells as a treatment for spinal cord injury. We are also conducting a Phase I/II clinical trial in dry AMD at three trial sites in the United States, and as of February 2014, have completed enrollment of the first of two planned patient cohorts with our HuCNS-SC cells. This cohort consisted of eight subjects. We expect to complete enrollment of the second cohort consisting of eight patients by the end of the second quarter of 2014.

We previously completed a Phase I clinical trial in infantile and late infantile neuronal ceroid lipofuscinosis (NCL), which showed that our HuCNS-SC cells were well tolerated and non-tumorigenic, and that there was evidence of engraftment and long-term survival of the transplanted HuCNS-SC cells. In October 2013, the results of a four-year, long-term follow up study of the patients from the initial Phase I study showed there were no long-term safety or tolerability issues associated with the cells up to five years post-transplantation. For a brief description of our significant therapeutic research and development programs see Overview “Therapeutic Product Development Programs” in the Business Section of Part I, Item 1 of this Form 10-K.

In April 2013, we entered into an agreement with the California Institute for Regenerative Medicine (CIRM) under which CIRM will provide up to approximately $19.3 million as a forgivable loan, in accordance with mutually agreed upon terms and conditions and CIRM regulations. The CIRM loan will help fund preclinical development of our HuCNS-SC cells for Alzheimer’s disease. We received an initial disbursement of $3.8 million under the CIRM Loan Agreement in July 2013, and a subsequent disbursement of $3.8 million in January 2014. For a brief description of our significant therapeutic research and development programs see Overview “Research and Development Programs” in the Business Section of Part I, Item 1 of this Form 10-K.

We are also engaged in developing and commercializing applications of our technologies to enable research, which we believe represent current and nearer-term commercial opportunities. Our portfolio of technologies includes cell technologies relating to embryonic stem cells, induced pluripotent stem (iPS) cells, and tissue-derived (adult) stem cells; expertise and infrastructure for providing cell-based assays for drug discovery; a cell culture products and antibody reagents business; and an intellectual property portfolio with claims relevant to cell processing, reprogramming and manipulation, as well as to gene targeting and insertion. Many of these enabling technologies were acquired in April 2009 as part of our acquisition of the operations of Stem Cell Sciences Plc (SCS).

We have not derived any revenue or cash flows from the sale or commercialization of any products except for license revenue for certain of our patented technologies and sales of products for use in stem cell research. As a result, we have incurred annual operating losses since inception and expect to incur substantial operating losses in the future. Therefore, we are dependent upon external financing, such as from equity and debt offerings, to finance our operations. Before we can derive revenue or cash inflows from the commercialization of any of our therapeutic product candidates, we will need to: (i) conduct substantial in vitro testing and characterization of our proprietary cell types, (ii) undertake preclinical and clinical testing for specific disease indications; (iii) develop, validate and scale-up manufacturing processes to produce these cell-based therapeutics, and (iv) obtain required regulatory approvals. These steps are risky, expensive and time consuming.

Overall, we expect our R&D expenses to be substantial and to increase for the foreseeable future as we continue the development and clinical investigation of our current and future product candidates. However, expenditures on R&D programs are subject to many uncertainties, including whether we develop our product candidates with a partner or independently. We cannot forecast with any degree of certainty which of our current product candidates will be subject to future collaboration, when such collaboration agreements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements. In addition, there are numerous factors associated with the successful commercialization of any of our cell-based

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therapeutics, including future trial design and regulatory requirements, many of which cannot be determined with accuracy at this time given the stage of our development and the novel nature of stem cell technologies. The regulatory pathways, both in the United States and internationally, are complex and fluid given the novel and, in general, clinically unproven nature of stem cell technologies. At this time, due to such uncertainties and inherent risks, we cannot estimate in a meaningful way the duration of, or the costs to complete, our R&D programs or whether, when or to what extent we will generate revenues or cash inflows from the commercialization and sale of any of our therapeutic product candidates. While we are currently focused on advancing each of our product development programs, our future R&D expenses will depend on the determinations we make as to the scientific and clinical prospects of each product candidate, as well as our ongoing assessment of the regulatory requirements and each product candidate’s commercial potential.

Given the early stage of development of our therapeutic product candidates, any estimates of when we may be able to commercialize one or more of these products would not be meaningful. Moreover, any estimate of the time and investment required to develop potential products based upon our proprietary HuCNS-SC technologies will change depending on the ultimate approach or approaches we take to pursue them, the results of preclinical and clinical studies, and the content and timing of decisions made by the FDA, Swissmedic, Health Canada, and other regulatory authorities. There can be no assurance that we will be able to develop any product successfully, or that we will be able to recover our development costs, whether upon commercialization of a developed product or otherwise. We cannot provide assurance that any of these programs will result in products that can be marketed or marketed profitably. If certain of our development-stage programs do not result in commercially viable products, our results of operations could be materially adversely affected.

The research markets served by our tools and technologies products are highly competitive, complex and dynamic. Technological advances and scientific discoveries have accelerated the pace of change in biological research, and stem cell technologies have been evolving particularly fast. We compete mainly by focusing on specialty media and antibody reagent products and human cell lines where we believe our expertise, intellectual property and reputation give us competitive advantage. We believe that, in this particular market niche, our products and technologies offer customers specific advantages over those offered by our competitors. We compete by offering innovative, quality-controlled products, consistently made and designed to produce reproducible results. For the year ended December 31, 2013, we generated revenues from the sale of specialty cell culture products of approximately $998,000. We can give no assurances that we will be able to continue to generate such revenues in the future.

Significant Events

Therapeutic Product Development

In February 2013, the first patient cohort in our Phase I/II clinical trial of our proprietary HuCNS-SC cells for chronic spinal cord injury completed the trial. The data from this first cohort continued to demonstrate a favorable safety profile, and showed that the considerable gains in sensory function observed at the six month assessment in two of the three patients had persisted to the 12 month assessment. The third patient remained stable.

In April 2013, we added the Byers Eye Institute at Stanford, located in Palo Alto, California, as a second site for our Phase I/II clinical trial of our proprietary HuCNS-SC cells in dry AMD.

In April 2013, we entered into an agreement with CIRM under which CIRM will provide up to approximately $19.3 million to help fund preclinical development and IND-enabling activities of our HuCNS-SC cells for Alzheimer’s disease. The funding, which will be in the form of a forgivable loan, was awarded under CIRM’s Disease Team Therapy Development Award program (RFA 10-05) in September 2012. The goal of the research will be to file an Investigational New Drug application with the U.S. Food and Drug Administration within four years.

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In June 2013, Health Canada authorized us to expand our Phase I/II clinical trial for chronic spinal cord injury into Canada. The Phase I/II trial is designed to evaluate the safety and preliminary efficacy of our proprietary HuCNS-SC cells as a treatment for chronic spinal cord injury.

In July 2013, we formally launched our Alzheimer’s disease program, which is being supported by CIRM. The goal of the project is to file, within four years, an Investigational New Drug (IND) application with the U.S. Food and Drug Administration to evaluate our HuCNS-SC cells as a potential therapeutic for Alzheimer’s disease. CIRM has agreed to provide approximately $19.3 million in the form of a forgivable loan to help fund our preclinical development and IND-enabling activities, and in July we received an initial disbursement of $3.8 million from CIRM. The funding was awarded under CIRM’s Disease Team Therapy Development Award program (RFA 10-05) in September 2012. In January 2014, we received a second disbursement of $3.8 million.

In August 2013, we presented data which show that, two years after transplantation of our HuCNS-SC cells into patients with PMD, the evidence of myelination, by magnetic resonance imaging (MRI), is more pronounced compared to one year post-transplantation, the gains in neurological function reported after one year were maintained, and there were no safety concerns. The neurological and MRI changes suggest a departure from the natural history of the disease and may represent signals of a clinical effect.

In September 2013, we published a comprehensive overview of the therapeutic potential and results from early clinical trials of our HuCNS-SC cells. The paper was published in Stem Cell Research & Therapy, an international peer-reviewed journal considered to be the major forum for translational research into stem cell therapies.

In September 2013, we dosed the first high-dose patient in our Phase I/II clinical trial in dry AMD. The patient, the fifth overall in the 16-patient trial, was transplanted with one million of our HuCNS-SC cells. The first four patients each received a dose of 200,000 cells. An independent Data Safety Monitoring Committee conducted a review of the trial data related to the first four patients, and found no safety issues to preclude the trial from proceeding to the high dose.

In September 2013, we published preclinical data confirming that our HuCNS-SC cells preserve photoreceptor cells and visual function in a widely used model of retinal degeneration. The data show not only that HuCNS-SC cells preserve the number of photoreceptors that would otherwise be lost, but also that the surviving photoreceptors appear healthy and normal, and maintain their synaptic connection to other important cells necessary for visual function. The study was published in Investigative Ophthalmology and Visual Science (IVOS), the peer-reviewed journal of the Association for Research in Vision and Ophthalmology.

In October 2013, the FDA authorized our IND application for clinical testing of our HuCNS-SC cells as a treatment for spinal cord injury. In October 2013, we presented the results of a four-year observation study in patients with NCL, who had been transplanted with our HuCNS-SC cells in our initial Phase I study. Key results include long-term evidence of safety, up to five years post transplantation, for the surgical transplantation of the HuCNS-SC cells into multiple sites in the brain and at doses of up to one billion cells. The study results represent the first, and thus far only, multi-year data set following transplantation of neural stem cells into human subjects, and support the feasibility of our approach in multiple neurological disorders. The data was presented by our co-principal investigator in the studies, at the Congress of Neurological Surgeons Annual Meeting in San Francisco, California.

In January 2014, a team at the University of Calgary successfully transplanted its first subject in our Phase I/II clinical trial in chronic spinal cord injury, with our HuCNS-SC cells. The ninth subject to enroll in the trial, which was initiated in Switzerland, is the first spinal cord injury patient to have undergone transplantation in North America. This expansion from a single-site, single-country study to a multi-site, multi-country program accelerates the current trial, which should complete enrollment of the remaining patients in the first quarter of 2014.

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In February 2014, we completed enrollment of the first of two planned patient cohorts in our clinical trial of our proprietary HuCNS-SC cells for AMD. This cohort consisted of eight subjects, four of whom each received 200,000 cells and four of whom each received 1,000,000 cells. We expect to complete enrollment of the second cohort consisting of eight patients by the end of the second quarter of 2014, and we expect to initiate a controlled phase II efficacy proof-of-concept study by year end.

Financing and Other Business-related Activities

In March 2013, we acquired certain patents and patent applications from NsGene A/S, a Danish company. These patents and patent applications claim a purified population of GFAP+ Nestin+ precursor cells in which one or more of the cells are capable of differentiating into neurons.

In April 2013, we closed a $10 million loan from Silicon Valley Bank (SVB). The loan has a three-year term and the loan funds will be used for general corporate purposes.

In June 2013, we entered into an agreement with an institutional investor, under which we have the right to sell up to $30.0 million of common stock to the institutional investor. Proceeds from any sales of stock under this agreement will be used for general corporate purposes. Under the terms of the agreement, we immediately sold 1,645,639 in shares of our common stock to the institutional investor at a purchase price of $1.823 per share and received gross proceeds of $3.0 million. We terminated this agreement in October 2013.

In October 2013, we sold a total of 12,845,500 units in an underwritten public offering at a price of $1.45 per unit and received total proceeds, net of offering expenses, underwriting discounts and commissions, of approximately $17.3 million. Each unit sold consisted of one share of common stock, par value $.01 per share, and a warrant to purchase one half share of common stock. The warrants have an exercise price of $1.80 per share, are exercisable immediately, and will expire five years from the date of issuance.

In October 2013, we acquired from NeuroSpheres the patents we had licensed on an exclusive worldwide basis, including the six patents that are the subject of our patent infringement litigation against Neuralstem. As consideration for the patents, we will issue 139,548 shares of unregistered common stock to NeuroSpheres. In connection with the acquisition, all preexisting agreements were terminated, including the license agreements, which thereby relieved us of further milestone and royalty payments to NeuroSpheres.

In November 2013, we announced that Greg Schiffman will join our executive team as Chief Financial Officer and Executive Vice President of Finance, effective January 1, 2014. In his new role, Mr. Schiffman will be responsible for all aspects of the Company’s financing activities, financial reporting and controls, corporate communications, and investor relations.

Critical Accounting Policies and the Use of Estimates

The accompanying discussion and analysis of our financial condition and results of operations is based on our Consolidated Financial Statements and the related disclosures, which have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP). The preparation of these Consolidated Financial Statements requires management to make estimates, assumptions, and judgments that affect the reported amounts in our Consolidated Financial Statements and accompanying notes. These estimates form the basis for making judgments about the carrying values of assets and liabilities. We base our estimates and judgments on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, and we have established internal controls related to the preparation of these estimates. Actual results and the timing of the results could differ materially from these estimates.

Warrant Liability

We account for our warrants in accordance with U.S. GAAP which defines how freestanding contracts that are indexed to and potentially settled in a company’s own stock should be measured and classified. Authoritative

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accounting guidance prescribes that only warrants issued by us under contracts that cannot be net-cash settled, and are both indexed to and settled in our common stock, can be classified as equity. As part of both our November 2008 and November 2009 financings, we issued warrants with five year terms to purchase 1,034,483 and 400,000 shares of our common stock at $23.00 and $15.00 per share, respectively. As part of our December 2011 financing, we issued Series A Warrants with a five year term to purchase 8,000,000 shares at $1.40 per share and Series B Warrants with a ninety trading day term to purchase 8,000,000 units at $1.25 per unit. Each unit underlying the Series B Warrants consisted of one share of our common stock and one Series A Warrant. In the first and second quarter of 2012, an aggregate of 2,700,000 Series B Warrants were exercised. For the exercise of these warrants, we issued 2,700,000 shares of our common stock and 2,700,000 Series A Warrants. The remaining 5,300,000 Series B Warrants expired unexercised by their terms on May 2, 2012. As terms of the warrants issued in 2008 and 2009, as well as the Series A and Series B Warrants, do not meet the specific conditions for equity classification, we are required to classify the fair value of these warrants as a liability, with subsequent changes in fair value to be recorded as income (loss) due to change in fair value of warrant liability. The fair value of the warrants issued in the 2008 and 2009 financings is determined using the Black-Scholes-Merton (Black-Scholes) option pricing model and the fair value of the Series A and Series B Warrants is determined using a Monte Carlo simulation model (see Note 13, “Warrant Liability”). The fair value is affected by changes in inputs to these models including our stock price, expected stock price volatility, the contractual term, and the risk-free interest rate. The use of a Monte Carlo simulation model requires input of additional assumptions including the progress of our R&D programs and its affect on potential future financings. We will continue to classify the fair value of the warrants as a liability until the warrants are exercised, expire or are amended in a way that would no longer require these warrants to be classified as a liability. The estimated fair value of our warrant liability at December 31, 2013, was approximately $5,542,000.

Stock-Based Compensation

U.S. GAAP requires us to recognize expense related to the fair value of our stock-based compensation awards, including employee stock options and restricted stock units. Employee stock-based compensation is estimated at the date of grant based on the award’s fair value using the Black-Scholes option pricing model and is recognized as expense ratably over the requisite service period. The Black-Scholes option pricing model requires the use of certain assumptions, the most significant of which are our estimates of the expected volatility of the market price of our stock, the expected term of the award, and the risk-free interest rate. Our estimate of the expected volatility is based on historical volatility. The expected term represents the period during which our stock-based awards are expected to be outstanding. In 2013, we estimated this amount based on historical experience of similar awards, giving consideration to the contractual terms of the awards, vesting requirements, and expectation of future employee behavior, including post-vesting terminations. Our estimate of the risk-free interest rate is based on U.S. Treasury debt securities with maturities close to the expected term of the option as of the date of grant. We review our valuation assumptions at each grant date and, as a result, our assumptions in future periods may change. At the end of each reporting period we estimate forfeiture rates based on our historical experience within separate groups of employees and adjust stock-based compensation expense accordingly. For the year ended December 31, 2013, employee and external services stock-based compensation expense (stock options, restricted stock units and 401(k) Plan employer match in form of shares) was approximately $2,609,000. As of December 31, 2013, total compensation cost related to unvested stock options and restricted stock units not yet recognized was approximately $4,275,000, which is expected to be recognized as expense over a weighted-average period of 3.0 years.

Wind-down expenses

In connection with exiting our research and manufacturing operations in Lincoln, Rhode Island, and the relocation of our corporate headquarters and remaining research laboratories to California in October 1999, we provided a reserve for our estimate of the exit cost obligation. The reserve was for the estimated costs of our former research and administrative facility in Lincoln, which we held on a lease that terminated on June 30, 2013. We periodically re-evaluated and adjusted the reserve after considering various factors such as our lease payments through to the end of the lease, operating expenses, the real estate market in Rhode Island, and

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estimated subtenant income based on actual and projected occupancy. We have closed this reserve as our lease and related obligations terminated on June 30, 2013. See Note 11 “Wind-down and exit costs” in the Notes to the Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information.

Goodwill and Other Intangible Assets (Patent and License Costs)

Goodwill of approximately $2,139,000 at December 31, 2013, relates to the acquisition of SCS operations. Goodwill and intangible assets deemed to have indefinite lives are not amortized but are subject to annual impairment tests. If the assumptions and estimates used to allocate the purchase price are not correct, or if business conditions change, purchase price adjustments or future asset impairment charges could be required. We test goodwill for impairment on an annual basis or more frequently if we believe indicators of impairment exist. Impairment evaluations involve management estimates of asset useful lives and future cash flows. Significant management judgment is required in the forecasts of future operating results that are used in the evaluations, and it is possible, even likely, that the plans and estimates used may be incorrect. If our actual results, or the plans and estimates used in future impairment analysis are lower than the original estimates used to assess the recoverability of these assets, we could incur additional impairment charges in a future period. We completed our annual impairment testing during the fourth quarter of 2013, and determined that there was no impairment of goodwill.

Other intangible assets, net were approximately $1,836,000 at December 31, 2013. Intangible assets with finite useful lives are amortized generally on a straight-line basis over the periods benefited. Intangible assets are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Prior to fiscal year 2001, we capitalized certain patent costs, which are being amortized over the estimated life of the patent and would be expensed at the time such patents are deemed to have no continuing value. Since 2001, all patent costs are expensed as incurred. License costs are capitalized and amortized over the estimated life of the license agreement. In December 2011, in part because of management’s decision to focus on our therapeutic product development programs and not to allocate time and resources to the assays technology, we determined that we could not predict the future cash flows from the intangible IPR&D asset related to the assays technology. Therefore, we determined that the intangible asset was impaired and wrote off the approximately $655,000 carrying value of the asset.

Impairment of Long-Lived Tangible Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If property, plant, and equipment are considered to be impaired, the impairment to be recognized equals the amount by which the carrying value of the assets exceeds its estimated fair market value. No such impairment was recognized during the year 2013.

Loan Payable

In April 2013, we entered into a Loan Agreement with Silicon Valley Bank (SVB) and received loan proceeds of $9,900,000, net of a $100,000 cash discount. The loan has a three-year term and bears interest at an annual rate of 6%. The loan obligations are secured by a first priority security interest on substantially all of our assets excluding intellectual property. There is also a final $1,000,000 fee payable at the end of the term which is being expensed over the term of the loan using the effective interest method. In conjunction with the Loan Agreement, we issued to SVB a ten year warrant to acquire 293,531 shares of common stock at an exercise price of $1.7034 per share. The warrant is immediately exercisable and expires in April 2023. We estimated the fair value of the warrant to be approximately $388,000 using the Black-Scholes option pricing model. We applied the relative fair value method to allocate the $9,900,000 net proceeds between the loan and warrant. The approximately $388,000 fair value allocated to the warrant was recorded as an increase to additional paid-in capital and as a discount to loan payable. Approximately $9,512,000 was assigned to the loan and was recorded as the initial carrying amount of the loan payable, net of discount. The approximately $388,000 fair value of the

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warrant and the $100,000 cash discount are both being amortized as additional interest expense over the term of the loan using the effective interest rate method. We also incurred loan issuance costs of approximately $117,000, which are recorded as deferred financing costs on the accompanying consolidated balance sheet and are being amortized to interest expense over the term of the Loan Agreement using the effective interest rate method. The effective interest rate used to amortize the deferred financing costs and the discount (including the fair value of the warrant and the cash discount), and for the accretion of the final payment, is 9.0%.

In April 2013, we entered into an agreement with the California Institute for Regenerative Medicine (CIRM) (the CIRM Loan Agreement) under which CIRM will provide up to approximately $19.3 million to help fund preclinical development and IND-enabling activities of our HuCNS-SC cells for Alzheimer’s disease. The funding is in the form of a forgivable loan, in accordance with mutually agreed upon terms and conditions and CIRM regulations, and is expected to be disbursed periodically by CIRM over the four-year project period subject to a number of preconditions, including the achievement of certain progress milestones and compliance with certain financial covenants. The loan is unsecured and the term of the loan is ten years and may be extended under certain circumstances. Initially, the loan will bear interest at the one year LIBOR rate plus two percent and will increase by 1% each year after year five. Interest will accrue with the first disbursement of loan funds, but we will not begin paying interest until year six. Repayment of the principal and any accrued and unpaid interest will be due and payable at the end of the term. We can prepay the CIRM loan at our election, either in whole or in part at any time and without a prepayment fee. In addition, the loan is forgivable so that our obligation to repay will be contingent upon the success of our HuCNS-SC cells as a treatment for Alzheimer’s disease. In July 2013, we received approximately $3.8 million as initial disbursement of the loan provided under the CIRM Loan Agreement, and a second disbursement of approximately $3.8 million in January 2014.

We classified our loan obligations with SVB and CIRM as loan payable, net of discount, current and non-current on our Consolidated Balance Sheet. See Note 14 “Loan payable” in the Notes to the Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information.

Income Taxes

When accounting for income taxes, we recognize deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of assets and liabilities. Income tax receivables and liabilities and deferred tax assets and liabilities are recognized based on the amounts that more likely than not will be sustained upon ultimate settlement with taxing authorities.

Developing our provision for income taxes and analyzing our tax positions requires significant judgment and knowledge of federal and state income tax laws, regulations and strategies, including the determination of deferred tax assets and liabilities and, any valuation allowances that may be required for deferred tax assets.

We assess the likelihood of realizing our deferred tax assets to determine whether an income tax valuation allowance is required. Based on such evidence that can be objectively verified, we determine whether it is more likely than not that all or a portion of the deferred tax assets will be realized. The main factors that we consider include:

Tax benefits associated with uncertain tax positions are recognized in the period in which one of the following conditions is satisfied: (1) the more likely than not recognition threshold is satisfied; (2) the position is ultimately settled through negotiation or litigation; or (3) the statute of limitations for the taxing authority to examine and challenge the position has expired. Tax benefits associated with an uncertain tax position are reversed in the period in which the more likely than not recognition threshold is no longer satisfied.

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We concluded that the realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. Accordingly, the net deferred tax assets have been fully offset by a valuation allowance.

Results of Operations

Our results of operations have varied significantly from year to year and quarter to quarter and may vary significantly in the future due to the occurrence of material recurring and nonrecurring events, including without limitation the receipt and payment of recurring and nonrecurring licensing payments, the initiation or termination of clinical studies, research collaborations and development programs for both cell-based therapeutic products and research tools, unpredictable or unanticipated manufacturing and supply costs, unanticipated capital expenditures necessary to support our business, developments in on-going patent prosecution and litigation, the on-going expenses to maintain our Rhode Island facilities, and the costs associated with operating our California and Cambridge, U.K. facilities.

Revenue

Revenue totaled approximately $1,203,000 in 2013, $1,368,000 in 2012, and $1,221,000 in 2011.

Total revenue in 2013 was approximately $1,203,000, which was 12% lower than total revenue in 2012. In 2013, revenue from product sales increased 17%, or approximately $142,000, compared to 2012. This increase was primarily attributable to increased unit volumes in our SC Proven line of media and reagents. In 2013, approximately 42% of our product sales were in Europe, 39% were in Asia, 15% were in North America, and 4% were in other geographies. Aggregate licensing, grant and other revenue in 2013 were approximately $205,000 which was 60% or approximately $306,000 lower than aggregate licensing, grant and other revenue in 2012. The decrease was primarily attributable to lower licensing revenue in 2013. The 2012 licensing revenue includes a one-time fee from a license agreement with genOway, under which we granted genOway a worldwide, exclusive license to our IRES technology for use in the development and commercialization of genetically engineered mice. Grant revenue in 2013 and 2012 were not significant.

Total revenue in 2012 was approximately $1,368,000, which was 12% higher than total revenue in 2011. In 2012, revenue from product sales increased 29%, or approximately $194,000, compared to 2011. This increase was primarily attributable to increased unit volumes in our SC Proven line of media and reagents. In 2012, approximately 70% of our product sales were in Europe, 13% were in North America, and 17% were in Asia. Aggregate licensing, grant and other revenue in 2012 were relatively flat in 2012 as compared to 2011. Grant revenue in 2012 was not significant and licensing fees in 2012 was primarily from a license agreement with genOway, under which we granted genOway a worldwide exclusive license to our IRES technology for use in the development and commercialization of genetically engineered mice.

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Operating Expenses

Operating expense totaled approximately $29,492,000 in 2013, $23,650,000 in 2012, and $29,082,000 in 2011.

Research and Development Expenses

Our R&D expenses consist primarily of salaries and related personnel expenses, costs associated with clinical trials and regulatory submissions, costs associated with preclinical activities such as toxicology studies, costs associated with cell processing and process development, certain patent-related costs such as licensing, facilities related costs such as depreciation, lab equipment, and supplies. Clinical trial expenses include payments to vendors such as clinical research organizations, contract manufacturers, clinical trial sites, laboratories for testing clinical samples and consultants. Cumulative R&D costs incurred since we refocused our activities on developing cell-based therapeutics (fiscal years 2000 through 2013) were approximately $188 million. Over this period, the majority of these cumulative costs were related to: (i) characterization of our proprietary HuCNS-SC cells, (ii) expenditures for toxicology and other preclinical studies, preparation and submission of applications to regulatory agencies to conduct clinical trials and obtaining regulatory clearance to initiate such trials, all with respect to our HuCNS-SC cells, (iii) preclinical studies and development of our human liver engrafting cells, (iv) costs associated with cell processing and process development, and (v) costs associated with our clinical studies.

We use and manage our R&D resources, including our employees and facilities, across various projects rather than on a project-by-project basis for the following reasons. The allocations of time and resources change as the needs and priorities of individual projects and programs change, and many of our researchers are assigned to more than one project at any given time. Furthermore, we are exploring multiple possible uses for each of our proprietary cell types, so much of our R&D effort is complementary to and supportive of each of these projects. Lastly, much of our R&D effort is focused on manufacturing processes, which can result in process improvements useful across cell types. We also use external service providers to assist in the conduct of our clinical trials, to manufacture certain of our product candidates and to provide various other R&D related products and services. Many of these costs and expenses are complementary to and supportive of each of our programs. Because we do not have a development collaborator for any of our product programs, we are currently responsible for all costs incurred with respect to our product candidates.

R&D expense totaled approximately $20,534,000 in 2013, as compared to $15,847,000 in 2012 and $19,938,000 in 2011. At December 31, 2013, we had 47 full-time employees working in research and development and laboratory support services as compared to 39 at December 31, 2012 and 40 at December 31, 2011.

2013 versus 2012. R&D expenses increased by approximately $4,687,000, or 30%, in 2013 compared to 2012. The increase was primarily attributable to (i) an increase of approximately $817,000 in expenses related to

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our clinical studies; primarily our Phase I/II clinical trial for the treatment of chronic spinal cord injury and our Phase I/II clinical trial in dry AMD, (ii) an increase in personnel costs of approximately $1,315,000 due to the addition of key personnel to strengthen our product development and clinical operations capabilities, (iii) an increase of approximately $1,361,000 in external services primarily related to preclinical studies of our HuCNS-SC cells, (iv) an increase of approximately $1,035,000 in supplies and validation expenses primarily related to manufacturing, quality control and process development activities to support our preclinical and clinical studies, and (v) an increase in other expenses of approximately $159,000. The increased R&D spending in 2013, reflects our on-going preparation to initiate a Phase II efficacy study in two indications (cervical spinal cord injury and AMD) in the second half of 2014.

2012 versus 2011. R&D expenses decreased by approximately $4,091,000, or 21%, in 2012 compared to 2011. This decrease was primarily attributable to (i) a decrease of approximately $1,143,000 in personnel expenses primarily due to the reduction in force effected in May 2011, (ii) a decrease of approximately $310,000 in operating expenses at our U.K. operations as we consolidated our activities at the site, (iii) a decrease in facilities expense of approximately $1,050,000 attributable to the relocation of our corporate headquarters and core research activities in July 2011; the 2011 period includes facilities expense from the previous lease which expired on August 31, 2011, (iv) a decrease of approximately $784,000 in external services and clinical studies; the 2011 period includes higher external services expenses primarily related to the preclinical studies of our HuCNS-SC cells for retinal disorders, other potential indications and quality tests of our cell banks, (v) a decrease of approximately $295,000 in expenses related to the clinical development within our CNS program, and (vi) a decrease in supplies and other operating expenses of approximately $509,000.

Selling, General and Administrative Expenses

Selling, general and administrative (SG&A) expenses are primarily comprised of salaries, benefits and other staff-related costs associated with sales and marketing, finance, legal, human resources, information technology, and other administrative personnel, facilities and overhead costs, and external legal, audit and other general and administrative services.

SG&A expenses totaled approximately $8,897,000 in 2013, compared with $7,447,000 in 2012 and $8,202,000 in 2011.

2013 versus 2012. SG&A expenses increased by approximately $1,449,000, or 19%, in 2013 compared to 2012. This increase was primarily attributable to (i) an increase of approximately $1,020,000 in external services, primarily legal fees, and (ii) an increase in personnel costs of approximately $462,000. The increase was partially offset by a decrease of approximately $33,000 in net other expenses.

2012 versus 2011. SG&A expenses decreased by approximately $755,000, or 9%, in 2012 compared to 2011. This decrease was primarily attributable to (i) a decrease of approximately $500,000 in external services, primarily legal fees, (ii) a decrease in facilities expense of approximately $194,000 attributable to the relocation of our corporate headquarters in July 2011; the lease on our previous corporate headquarters expired on August 31, 2011, and (iii) a net decrease of approximately $61,000 in other operating expenses.

Wind-down Expenses

In connection with our wind-down of our research and manufacturing operations in Lincoln, Rhode Island, and the relocation of our corporate headquarters and remaining research laboratories to California in October 1999, we provided a reserve for our exit cost obligation. The reserve was for the estimated costs of our former research and administrative facility in Lincoln, which we held on a lease that terminated on June 30, 2013. We periodically re-evaluated and adjusted the reserve after considering various factors such as our lease payments through to the end of the lease, operating expenses, the real estate market in Rhode Island, and estimated subtenant income based on actual and projected occupancy. The reserve was approximately $854,000 at December 31, 2012. In the first and second quarter of 2013, aggregate payments net of subtenant income of approximately $916,000 were recorded against this reserve and approximately $62,000 in aggregate was

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expensed as additional wind-down expenses. We have closed this reserve as the lease and our related obligations terminated on June 30, 2013. See Note 11 “Wind-down and exit costs,” in the Notes to Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information.

Other Income (Expense)

Other income totaled approximately $2,166,000 in 2013, compared with other expense of approximately $5,945,000 in 2012 and other income of $6,748,000 in 2011.

Change in Fair Value of Warrant Liability

We record changes in fair value of warrant liability as income or loss in our Consolidated Statements of Operations. We have warrants outstanding which were issued as part of several transactions since 2008 and have classified all these warrants as a liability. The fair value of the outstanding warrants is determined using various option pricing models, such as the Black-Scholes-Merton (Black-Scholes) option pricing model and a Monte Carlo simulation model, and is affected by changes in inputs to the various models, including our stock price, expected stock price volatility, the contractual term and the risk-free interest rate. The use of a Monte Carlo simulation model requires input of additional subjective assumptions including the progress of our R&D programs and its affect on potential future financings. The fair value of the warrant liability is revalued at the end of each reporting period. See Note 13 “Warrant Liability,” in the Notes to Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information on this transaction.

Interest Income

Interest income totaled approximately $11,000 in 2013, $16,000 in 2012, and $14,000 in 2011. Interest income in 2013 was not significant and is from the investment of our cash balances in money market accounts and short-term money market instruments that are highly liquid and that preserves capital.

Interest Expense

Interest expense was approximately $1,167,000 in 2013, $50,000 in 2012, and $71,000 in 2011. Interest expense for 2013 was primarily from the accretion of discount, amortization of deferred financing costs and accrual of interest related to our loan agreement with SVB, and accrued interest related to our loan agreement

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with CIRM. See Note 14 “Loan Payable,” in the Notes to Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information. The decrease in interest expense from 2011 to 2012 was primarily attributable to lower outstanding debt and capital lease balances.

Other Income (Expense), net

Other income, net totaled approximately $68,000 in 2013, $34,000 in 2012, and $109,000 in 2011.

Other income in 2013 includes approximately $61,000 of R&D tax credits due to our wholly-owned subsidiary Stem Cell Sciences (U.K.) Ltd. (SCS) and approximately $38,000 from a net gain on sale and disposal of equipment. The above income was offset by state franchise taxes of approximately $31,000. Other income, net in 2012 includes approximately $118,000 of R&D tax credits due to our wholly-owned subsidiary SCS. The above income was offset by state franchise taxes of approximately $35,000 and a loss on disposal of fixed assets of approximately $49,000. Other income, net in 2011 includes the receipt of approximately $150,000 as a break-up fee paid to us upon the expiration of an exclusivity period granted to a potential licensee. Other income, net was partially offset in 2011 by other expenses, primarily state franchise taxes.

Liquidity and Capital Resources

Since our inception, we have financed our operations through the sale of common and preferred stock, the issuance of long-term debt and capitalized lease obligations, revenue from research grants, license fees, product sales and interest income.

Total cash and highly liquid investments were approximately $30,585,000 at December 31, 2013, compared with approximately $22,372,000 at December 31, 2012, and $16,592,000 at December 31, 2011.

Net Cash Used in Operating Activities

Cash used in operating activities was approximately $23,286,000 in 2013, $19,869,000 in 2012, and $22,058,000 in 2011. Cash used in operating activities is primarily driven by our net loss as adjusted for non-cash charges and differences in the timing of operating cash flows.

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Net Cash Used in Investing Activities

Net cash from investing activities increased by approximately $19,692,000 in 2013 compared to 2012. The increase was primarily attributable to maturities of marketable debt securities in 2013. In 2013 we had net maturities of marketable debt securities of approximately $13,742,000 compared to net purchases of marketable securities of approximately $10,619,000 in 2012. This cash-inflow in 2013 was partially offset by an increase in net investment in leasehold improvements, equipment and other assets of approximately $4,669,000 in 2013 as compared to 2012. Net cash used in investing activities increased by approximately $7,270,000, or 212%, in 2012 compared to 2011. The increase was primarily attributable to an increase in net purchases of marketable debt securities in 2012 as compared to 2011. Our investment portfolio is comprised primarily of U.S. Treasury debt securities, which are classified as cash equivalents.

Net Cash Provided by Financing Activities

The increases in cash provided by financing activities from 2011 to 2013 were primarily attributable to higher net proceeds from sales of our common stock.

Listed below are key financing transactions entered into by us in 2013, 2012 and 2011:

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We have incurred significant operating losses and negative cash flows since inception. We have not achieved profitability and may not be able to realize sufficient revenue to achieve or sustain profitability in the future. We do not expect to be profitable in the next several years, but rather expect to incur additional operating losses. We have limited liquidity and capital resources and must obtain significant additional capital resources in order to sustain our product development efforts, for acquisition of technologies and intellectual property rights, for preclinical and clinical testing of our anticipated products, pursuit of regulatory approvals, acquisition of capital equipment, laboratory and office facilities, establishment of production capabilities, for selling, general and administrative expenses and other working capital requirements. We rely on cash balances and proceeds from equity and debt offerings, proceeds from the transfer or sale of our intellectual property rights, equipment, facilities or investments, and government grants and funding from collaborative arrangements, if obtainable, to fund our operations.

We intend to pursue opportunities to obtain additional financing in the future through equity and debt financings, grants and collaborative research arrangements. In December 2013, we filed with the SEC, and the SEC declared effective, a universal shelf registration statement which permits us to issue up to $100 million worth of registered debt and equity securities. Under this effective shelf registration, we have the flexibility to issue registered securities, from time to time, in one or more separate offerings or other transactions with the size, price and terms to be determined at the time of issuance. Registered securities issued using this shelf may be used to raise additional capital to fund our working capital and other corporate needs, for future acquisitions of assets, programs or businesses, and for other corporate purposes.

The source, timing and availability of any future financing will depend principally upon market conditions, interest rates and, more specifically, on our progress in our exploratory, preclinical and future clinical

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development programs. Funding may not be available when needed — at all, or on terms acceptable to us. Lack of necessary funds may require us, among other things, to delay, scale back or eliminate some or all of our research and product development programs, planned clinical trials, and/or our capital expenditures or to license our potential products or technologies to third parties. In addition, the decline in economic activity, together with the deterioration of the credit and capital markets, could have an adverse impact on potential sources of future financing.

Commitments

See Note 12, “Commitments and Contingencies” in the Notes to Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information.

Off-Balance Sheet Arrangements

We have certain contractual arrangements that create potential risk for us and are not recognized in our Consolidated Balance Sheets. Discussed below are those off-balance sheet arrangements that have, or are reasonably likely to have, a material current or future effect on our financial condition, changes in financial condition, revenue or expenses, results of operations, liquidity, capital expenditures, or capital resources.

Operating Leases

We lease various real properties under operating leases that generally require us to pay taxes, insurance, maintenance, and minimum lease payments. Some of our leases have options to renew.

Operating Leases — California

In September 2010, we entered into a two-year sublease agreement with Caliper Life Sciences, Inc., for office and research space in a facility located in Mountain View, California. In June 2012, the sublease term was extended to and expired on September 30, 2013. We paid approximately $1,081,000 in aggregate as rent over the term of the lease.

In December 2010, we entered into a commercial lease agreement with BMR-Gateway Boulevard LLC (BMR), as landlord, for office and research space at BMR’s Pacific Research Center in Newark, California. The initial term of the lease is approximately eleven and one-half years and includes escalating rent payments which we recognize as lease operating expense on a straight-line basis. We will pay approximately $17,869,000 in aggregate as rent over the term of the lease to BMR. Deferred rent for this facility was approximately $1,434,000 as of December 31, 2013, and approximately $1,389,000 as of December 31, 2012.

In March 2013, we entered into a commercial lease agreement with Prologis, L.P. (Prologis), as landlord, for office and research space in Sunnyvale, California. The facility is for operations that support our clinical development activities. The initial term of the lease is ten years and includes escalating rent payments which we recognize as lease operating expense on a straight-line basis. We will pay approximately $3,497,000 in aggregate rent over the term of the lease. As part of the lease, Prologis has agreed to provide us financial allowances to build initial tenant improvements, subject to customary terms and conditions relating to landlord-funded tenant improvements. The tenant improvements are recorded as leasehold improvement assets and amortized over the term of the lease. The financial allowances are treated as a lease incentive and recorded as deferred rent which is amortized as reductions to lease expense over the lease term. Deferred rent for this facility was approximately $391,000 as of December 31, 2013.

Operating Leases — Rhode Island

We entered into a fifteen-year lease agreement for a scientific and administrative facility (SAF) in Rhode Island in connection with a sale and leaseback arrangement in 1997. The lease term expired on June 30, 2013.

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For the year 2013, we paid approximately $1,165,000 in operating lease payments and operating expenses net of sub-tenant income.

Operating Leases — United Kingdom

In January 2011, we amended the existing lease agreements of our wholly-owned subsidiary, Stem Cell Sciences (U.K.) Ltd, effectively reducing our leased office and lab space. The lease by its terms was extended to September 30, 2013. In October 2013, we signed a new three-year lease agreement for the leased space and expect to pay rent of approximately GBP 53,000 per annum. StemCells, Inc. is the guarantor of Stem Cell Sciences (U.K.) Ltd’s obligations under the existing lease. The lease gives SCS an option for early termination of the lease agreement.

With the exception of the operating leases discussed above, we have not entered into any significant off balance sheet financial arrangements and have not established any special purpose entities. We have not guaranteed any debts or commitments of other entities or entered into any options on non-financial assets. See Note 11, “Commitments and Contingencies,” in the Notes to Consolidated Financial Statements of Part II, Item 8 of this Form 10-K for further information.

Contractual Obligations

In the table below, we set forth our legally binding and enforceable contractual cash obligations at December 31, 2013: