RAMBUS INC - Annual Report: 2011 (Form 10-K)

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PART IV

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Form 10-K

Commission file number: 000-22339

RAMBUS INC.
(Exact name of registrant as specified in its charter)

Registrant's telephone number, including area code:
(408) 462-8000

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 ý    No o

          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 o    No ý

          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 ý    No o

          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 ý    No o

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

          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 Act). Yes o    No ý

          The aggregate market value of the Registrant's Common Stock held by non-affiliates of the Registrant as of June 30, 2011 was approximately $1.3 billion based upon the closing price reported for such date on The NASDAQ Global Select Market. For purposes of this disclosure, shares of Common Stock held by officers and directors of the Registrant and persons that may be deemed to be affiliates under the Act have been excluded. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

          The number of outstanding shares of the Registrant's Common Stock, $.001 par value, was 110,272,001 as of January 31, 2012.

DOCUMENTS INCORPORATED BY REFERENCE

          Certain information is incorporated into Part III of this report by reference to the Proxy Statement for the Registrant's annual meeting of stockholders to be held on or about April 26, 2012 to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Form 10-K.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This Annual Report on Form 10-K ("Annual Report") contains forward-looking statements. These forward-looking statements include, without limitation, predictions regarding the following aspects of our future:

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Success in the markets of our or our licensees' products;



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Sources of competition;



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Research and development costs and improvements in technology;



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Sources, amounts and concentration of revenue, including royalties;



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Success in renewing license agreements;



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Technology product development;



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Outcome and effect of current and potential future intellectual property litigation and other significant litigation;



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Acquisitions, mergers or strategic transactions and our related integration efforts;



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Pricing policies of our licensees;



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Engineering, marketing and general and administration expenses;



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Contract revenue;



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Operating results;



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International licenses and operations;



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Effects of changes in the economy and credit market on our industry and business;



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Deterioration of financial health of commercial counterparties and their ability to meet their obligations to us;



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Ability to identify, attract, motivate and retain qualified personnel;



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Growth in our business;



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Methods, estimates and judgments in accounting policies;



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Adoption of new accounting pronouncements;



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Effective tax rates;



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Realization of deferred tax assets/release of deferred tax valuation allowance;



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Trading price of our Common Stock;



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Internal control environment;



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Corporate governance;



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The level and terms of our outstanding debt;



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Resolution of the governmental agency matters involving us;



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Litigation expenses;



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Protection of intellectual property;



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Terms of our licenses;

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Amounts owed under licensing agreements;



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Indemnification and technical support obligations;



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Issuances of our securities, which could involve restrictive covenants or be dilutive to our existing stockholders;



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Interest and other income, net; and



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Likelihood of paying dividends or repurchasing securities.

        You can identify these and other forward-looking statements by the use of words such as "may," "future," "shall," "should," "expects," "plans," "anticipates," "believes," "estimates," "predicts," "intends," "potential," "continue," or the negative of such terms, or other comparable terminology. Forward-looking statements also include the assumptions underlying or relating to any of the foregoing statements.

        Actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under Item 1A, "Risk Factors." All forward-looking statements included in this document are based on our assessment of information available to us at this time. We assume no obligation to update any forward-looking statements.

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PART I

        Rambus, RDRAM™, XDR™, FlexIO™ and FlexPhase™ are trademarks or registered trademarks of Rambus Inc. Other trademarks that may be mentioned in this annual report on Form 10-K are the property of their respective owners.

        Industry terminology, used widely throughout this annual report, has been abbreviated and, as such, these abbreviations are defined below for your convenience:

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        From time to time we will refer to the abbreviated names of certain entities and, as such, have provided a chart to indicate the full names of those entities for your convenience.

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Item 1.    Business

        Rambus Inc., referred to as we, us or Rambus, was founded in 1990 and reincorporated in Delaware in March 1997. Our principal executive offices are located at 1050 Enterprise Way, Suite 700, Sunnyvale, California. Our Internet address is www.rambus.com. You can obtain copies of our Forms 10-K, 10-Q, 8-K, and other filings with the SEC, and all amendments to these filings, free of charge from our website as soon as reasonably practicable following our filing of any of these reports with the SEC. In addition, you may read and copy any material we file with the SEC at the SEC's Public Reference Room at 100 F Street NE, Room 1580, Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy, and information statements, and other information regarding registrants that file electronically with the SEC at www.sec.gov.

        We are a premier intellectual property and technology licensing company focusing on the creation, design, development and licensing of patented innovations, technologies and architectures that are foundational to nearly all digital electronics products and systems. Our mission is to continuously enrich the end-user experience of electronic systems through groundbreaking innovations and technologies designed to improve the performance, power efficiency, time-to-market and cost-effectiveness of the products, components and systems offered by market-leading companies in semiconductors, computing, tablets, handheld devices, mobile applications, gaming and graphics, high definition televisions, or HDTVs, and displays, general lighting, cryptography and data security. Our inventors and engineering teams focus on creating innovations designed to address the most challenging demands of each target market and industry.

        We generate revenue by licensing our patented innovations and technologies to market-leading companies that provide their products to the end-user customers or consumers. We believe we have established an unparalleled licensing platform and business model that will continue to foster the development of new foundational and leading innovations and technologies. By continuing to build upon this platform, our goal is to create additional licensing opportunities, and thereby perpetuate strong company operating performance and long-term stockholder value.

        While we have historically focused our efforts in the development of technologies for electronics memory and chip interfaces, we have been expanding our portfolio of inventions and solutions to address additional markets in lighting, displays, chip and system security, digital media, as well as new areas within the semiconductor industry, such as imaging and non-volatile memory. We intend to continue our growth into new technology fields, consistent with our mission to create great value through our innovations and to make those technologies available through our licensing business model. Key to our efforts, both in our current businesses and in any new area of diversification, will be hiring and retaining world-class inventors, scientists and engineers to lead the development of inventions and technology solutions for these fields of focus, and the management and business support personnel necessary to execute our plans and strategies.

        Rambus has two business groups: the Semiconductor Business Group, or SBG, which focuses on the design, development and licensing of technology that is semiconductor based, and the New Business Group, or NBG, which focuses on the design, development and licensing of technologies for lighting, displays, chip and system security, anti-counterfeiting, digital media and other markets.

        As of December 31, 2011, our semiconductor, lighting, display, security and other technologies are covered by 1,386 U.S. and foreign patents. Additionally, we have 1,059 patent applications pending. Some of the patents and pending patent applications are derived from a common parent patent application or are foreign counterpart patent applications. We have a program to file applications for and obtain patents in the United States and in selected foreign countries where we believe filing for such protection is appropriate and would further our overall business strategy and objectives. In some instances, obtaining appropriate levels of protection may involve prosecuting continuation and

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counterpart patent applications based on a common parent application. We believe that our patented innovations provide our customers means to achieve improved performance, lower risk, greater cost-effectiveness and other benefits in their products and services.

        Our patented inventions and technology solutions are offered to our customers through either a patent license or a solutions license. Our revenues are primarily derived from patent licenses, through which we provide our customers a license to use some specified portion of our broad portfolio of patented inventions. The patent license essentially provides our customers with a defined right to use our patented innovations in the customer's own digital electronics products, systems or services, as applicable. The patent licenses may also define the specific field of use where our customers may employ our inventions in their products. Patent license agreements are structured with fixed, variable or a hybrid of fixed and variable royalty payments over certain defined periods.

        We also offer our customers solutions licenses to support the implementation and adoption of our technology in their products or services. Our solutions license offerings include a range of solutions developed by Rambus, which include "leadership" solutions (which are Rambus-proprietary solutions widely licensed to our customers) and industry-standard solutions that we provide to our customers under license for incorporation into our customers' digital electronics products and systems. We offer a range of services as part of our solutions licenses which can include know-how and technology transfer, product design and development, system integration, supply chain consulting and other services. These solutions license agreements may have both a fixed price (non-recurring) component and ongoing royalties. Further, under solutions licenses, our customers typically receive licenses to our patents necessary to implement these solutions in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts with us.

Background

Semiconductor Technology

        The demand for increased performance in computers, tablets, smartphones, consumer electronics and other electronic systems rises dramatically with each passing year. Semiconductor and system designers face key challenges in sustaining this pace of innovation. Since battery technology improves modestly over time, mobile device designers face adding increased functionality and higher performance with only small increases in power budget. For plug-in systems, there is a strong desire to reduce power consumption for both economic and environmental reasons while still providing increased computing capability and more visually compelling displays. At the chip level, it becomes increasingly difficult to maintain signal integrity and power efficiency as data transfer speeds rise to support more powerful, multi-core processors.

        To address these challenges and enable the continued improvement of electronics systems requires ongoing innovation. The many contributions and patented innovations developed by Rambus' scientists and engineers have been, and continue to be, critical in addressing some of the most difficult chip and system challenges. We have developed what we believe are the world's fastest memory solutions delivering breakthrough performance at unmatched power efficiency. Our patented innovations can deliver the memory bandwidth and throughput needed to unleash the potential of multi-core processors.

Lighting and Display Technology

        The continued evolution of the LED as a bright, reliable and energy-efficient light source creates significant market opportunities in consumer electronics and in general lighting. Harnessing the benefits of LEDs, however, presents a new set of challenges for companies that offer and provide electronics and lighting products and solutions. Since LED backlighting solutions are increasingly pervasive in liquid crystal displays, or LCDs, for computers, smartphones, tablets, game systems, HDTVs and any

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user interface incorporating an active display, the continued move to higher resolution displays across these products requires more LEDs per system. The increased usage of LEDs is thereby creating a need for increased power efficiency since the LED backlight is the primary source of power consumption in many consumer electronics products, including smartphones. While LEDs may offer the promise of long operating life, energy efficiency and improved aesthetics, there are significant technical challenges with the adoption of LEDs that relate to their comparatively high cost, illumination effectiveness and design and form factor constraints. These challenges present a significant market opportunity for Rambus.

        We believe that our patented innovations in lighting and display technologies represent significant value to applications, products and systems that use or will adopt LED-based lighting. For example, our patented innovations in backlighting can enable what we believe to be some of the thinnest, most power-efficient and cost-effective LCD displays for smartphones, tablets, computers and HDTVs. In addition, our goal is that our patented innovations and technologies in general lighting will offer revolutionary and breakthrough solutions that will provide exceptional quality and control of illumination in form factors unconstrained by legacy lighting products and systems. We believe that these breakthrough patented innovations and technologies advance our mission of enriching the consumer experience of electronic products and systems and represent additional significant licensing opportunities in growing markets. We continue to focus significant resources and effort to help bring these new products to market under solutions license agreements with leading companies in the industry.

Chip and System Security Technology

        As electronics systems grow increasingly sophisticated, the information and data stored and transferred through these devices increases in value. For example, smartphones and game systems store personal data, conduct financial transactions and e-commerce, and deliver copyrighted content including movies, music and games. Unless these systems can be made reliably secure, their usefulness to consumers and content owners decreases dramatically. Examples of high profile security breaches of electronics products and systems clearly illustrate the critical importance of data and information security. Security is also a significant risk and concern for companies that offer branded accessories and consumables, such as printing peripherals and consumable inks. Counterfeit products have the effect of decreasing earning potential, damaging a company's brand image and exposing consumers to low quality or defective goods. Proper security measures may be used to effectively eliminate certain types of counterfeiting through the use of encryption related technologies.

        Through our acquisition of CRI, we own a portfolio of patented inventions and technology solutions that we believe provide an unrivaled level of security in electronic devices and systems. CRI's patented DPA countermeasures are critical in designing secure semiconductors and products, and are used to protect devices against side channel attacks such as monitoring the variations in power consumption or electromagnetic emissions of a device. In addition, CRI's CryptoFirewall cores provide a robust hardware-based solution to protect electronics systems from the full range of attacks. We believe our hardware level security is vastly superior to many software-based security solutions, and provides a robust platform for building effective security applications.

Additional Technologies

        Consistent with our mission of continuously enriching the end-user experience of electronic systems, Rambus' scientists and engineers are focusing on inventing, developing and expanding our patented innovations and solutions into new technology areas. As electronic systems continue their rapid evolution, new opportunities for innovation abound, which offer new avenues for licensing and long-term growth.

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Our Offerings

Patented Innovations

        Royalties represent a substantial majority of our total revenue. We derive the majority of our royalty revenue by licensing our broad portfolio of patents to our customers. These licenses may cover part or all of our patent portfolio across our breadth of technologies. Leading semiconductor and system companies such as AMD, Broadcom, Elpida, Freescale, Fujitsu, Intel, Panasonic, Renesas, Samsung and Toshiba have licensed our patents for use in their own products. Examples of the many patented innovations in our portfolio include, and have included:

        Dual Edge Clocking which is designed to allow data to be sent on both the leading and trailing edge of the clock pulse, effectively doubling the transfer rate out of a memory core without the need for higher system clock speeds.

        FlexPhase™ technology which synchronizes data output and compensates for circuit timing errors in high-speed memory systems.

        Module Threading which improves the throughput and power efficiency of a memory module by applying parallelism to module data accesses.

        MicroLens® optics technology which is used in LED edge-lit lighting applications delivers superior brightness, directional control and uniformity of illumination.

        TruEdge™ technology which provides for the highly-efficient transfer of light from LEDs into a light guide used to distribute the light

        Differential Power Analysis ("DPA") Countermeasures which secure electronic devices and systems from side-channel attacks seeking to access the encrypted key.

Technology Solutions and Enabling Services

        We license a range of technology solutions including our leadership and industry-standard solutions to customers for use in their digital electronics products and systems. Our customers include leading companies such as Elpida, GE, IBM, Panasonic, Samsung, Sony and Toshiba. Due to the often complex nature of implementing our technologies, we provide engineering services under certain of these licenses to help our customers successfully integrate our technology solutions into their semiconductor and system products. Licensees may also receive, in addition to their solutions license agreements, patent licenses as necessary to implement the technology in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts.

        Our leadership technology solutions include the XDR™ and XDR™2 memory architectures, the FlexIO™ processor bus, Pentelic™ lighting solutions, and the CryptoFirewall™ security core.

        The XDR™ Memory Architecture enables what we believe to be the world's fastest production DRAM with operation up to 7.2Gb/s. XDR™ DRAM is the main memory solution for Sony Computer Entertainment's PlayStation®3 as well as for Texas Instrument's latest generation of Digital Light Processing, or DLP, projectors.

        The XDR™2 Memory Architecture incorporates new innovations, including DRAM micro-threading, to deliver the world's highest performance for graphics intensive applications such as gaming and digital video.

        The FlexIO™ Processor Bus is a high speed chip-to-chip interface. It is one of our two key chip interface products that enable the Cell BE processor co-developed by Sony, Toshiba and IBM. In the PlayStation®3, the FlexIO™ bus provides the interface between the Cell BE, the RSX graphics processor and the SouthBridge chip.

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        The Pentelic™ Lighting Solutions offer superior efficiency, control of light directionality and freedom of design to create beautiful and functional LED-based lighting products.

        The CryptoFirewall™ Security Core delivers an unmatched level of protection for digital media, such as in pay TV systems, and for protection against counterfeiting of accessories and consumables.

        In our semiconductor business, we also offer industry-standard chip interface solutions, including DDRx (where the "x" is a number that represents a version), as well as digital logic controllers for PCI Express and other industry standard interfaces.

Design and Manufacturing

        Our technology solutions are developed with high-volume commercial manufacturing processes in mind. Our solutions can be delivered in a number of ways, from reference designs to full turnkey custom developments. A reference design engagement might include an architectural specification, data sheet, theory of operation and implementation guides. A custom development would entail a specific design implementation optimized for the licensee's manufacturing process. In some cases, we may provide supply chain enablement services where we assist our customers in designing and establishment of certain manufacturing processes to implement our technologies in their product offerings.

Target Markets, Applications and Customers

        We work with leading and emerging semiconductor and digital electronics products and system customers to enable their products and services. We engage with our customers across the entire product life cycle, from system architecture development, to component design, to system integration, to production ramp-up through product maturation. Our patented innovations and technologies are incorporated into a broad range of high-volume applications in computing, gaming and graphics, lighting, consumer electronics, and mobile markets. System level products that utilize our patented inventions and/or solutions include smartphones, tablets, personal computers, servers, printers, video projectors, game systems, HDTVs, TV set-top boxes and LED-based lighting offered by such companies as DIRECTV, Fujitsu, GE, IBM, Panasonic, Samsung, Sony and Toshiba.

Our Strategy

        The key elements of our strategy are as follows:

        Innovate:    Develop and patent our innovative technology to provide fundamental competitive advantage when incorporated into semiconductors, and digital electronics products and systems.

        Drive Adoption:    Communicate the advantages of our patented innovations and technologies to the industry and encourage its adoption through demonstrations and incorporation in the products of select customers.

        Monetize:    License our patented inventions and technology solutions to customers for use in their semiconductor and system products.

        We believe that the successful execution of this strategy requires an exceptional and unparalleled licensing platform and business model that relies on the skills and talent of our employees. Accordingly, we seek to hire and retain world class scientific and engineering expertise in all of our fields of technological focus, as well as the executive management and operating personnel required to successfully execute our business strategy. In order to attract the quality of employees required for this business model, we have created an environment and culture that encourages, fosters and supports research, development and innovation in breakthrough technologies with significant opportunities for broad industry adoption through licensing. We believe that we have created a compelling company for

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inventors and innovators who are able to work within a business model and platform that focuses on intellectual property development and licensing to drive strong future growth.

Research and Development

        Our ability to compete in the future will be substantially dependent on our ability to develop and patent key innovations that meet the future needs of a dynamic market. To this end, we have assembled a team of highly skilled engineers and scientists whose activities are focused on continually developing new innovations within our chosen technology fields. Using this foundation of patented innovations, our technical teams develop new solutions that enable increased performance, greater power efficiency, increased levels of security, as well as other improvements and benefits. Our solution design and development process is a multi-disciplinary effort requiring expertise in system architecture, digital and analog circuit design and layout, semiconductor process characteristics, packaging, printed circuit board routing, signal integrity, high-speed testing techniques, optical design, thermal management, material science, cryptography, software design and development, and system integration.

        As of December 31, 2011, we had approximately 280 employees in our engineering departments, representing approximately 62% of our total employees. A significant number of our scientists and engineers spend all or a portion of their time on research and development. For the years ended December 31, 2011, 2010 and 2009, research and development expenses were $115.7 million, $92.7 million and $67.3 million, respectively, including stock-based compensation of approximately $10.5 million, $10.2 million and $9.7 million, respectively. For the year ended December 31, 2011, research and development expenses also included $15.7 million for retention bonuses for CRI engineers who joined Rambus in June 2011. Since innovation is critical to our future success, we expect to continue to invest substantial funds in research and development activities. In addition, because our license and support agreements often call for us to provide engineering support, a portion of our total engineering costs are allocated to the cost of contract revenue.

Competition

        The electronics industry is intensely competitive and has been impacted by price erosion, rapid technological change, short product life cycles, cyclical market patterns and increasing foreign and domestic competition. We face competition from semiconductor and digital electronics products and systems companies, as well as other intellectual property companies, all of whom may provide their own technologies.

        We believe that our principal competition for our technologies may come from our prospective licensees, some of whom are evaluating and developing products based on technologies that they contend or may contend will not require a license from us. Some of our competitors use a system-level design approach similar to ours, including activities such as board and package design, power and signal integrity analysis, and thermal management. Many of these companies are larger and may have better access to financial, technical and other resources than we possess.

        To the extent that alternatives might provide comparable system performance at lower than or similar cost to our technologies, or are perceived to require the payment of no or lower royalties, or to the extent other factors influence the industry, our licensees and prospective licensees may adopt and promote alternative technologies. Even to the extent we determine that such alternative technologies infringe our patents, there can be no assurance that we would be able to negotiate agreements that would result in royalties being paid to us without litigation, which could be costly and the results of which would be uncertain. Litigation has been, and may continue to be required to enforce and protect our intellectual property rights, as well as the substantial investments undertaken to research and develop our innovations and technologies.

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Employees

        As of December 31, 2011, we have 456 employees. None of our employees are covered by collective bargaining agreements. As noted above, we believe that our future success is dependent on our continued ability to identify, attract, motivate and retain qualified personnel. To date, we believe that we have been successful in recruiting qualified employees and that our relationship with our employees is good.

Patents and Intellectual Property Protection

        We maintain and support an active program to protect our intellectual property, primarily through the filing of patent applications and the defense of issued patents against infringement. As of December 31, 2011, we have 1,386 U.S. and foreign patents on various aspects of our technology, with expiration dates ranging from 2012 to 2030, and we have 1,059 pending patent applications. These patents and patent applications cover important inventions in semiconductor, lighting, display, security and other technologies. Some of the patents and pending patent applications are derived from a common parent patent application or are foreign counterpart patent applications. We have a program to file applications for and obtain patents in the United States and in selected foreign countries where we believe filing for such protection is appropriate and would further our overall business strategy and objectives. In some instances, obtaining appropriate levels of protection may involve prosecuting continuation and counterpart patent applications based on a common parent application. In addition, we attempt to protect our trade secrets and other proprietary information through agreements with current and prospective licensees, and confidentiality agreements with employees and consultants and other security measures. We also rely on trademarks and trade secret laws to protect our intellectual property.

Business Segment Data, Customers and Our Foreign Operations

        Prior to 2010, we operated in a single industry segment, the design, development and licensing of memory and logic interfaces, lighting and optoelectronics, and other technologies. In 2010, we reorganized, and as a result, currently have two business groups: SBG which focuses on the design, development and licensing of technology that is semiconductor based, and NBG which focuses on the design, development and licensing of technologies for lighting, displays, chip and system security, anti-counterfeiting, digital media and other markets. As of December 31, 2011, only SBG was considered a reportable segment as it met the quantitative thresholds for disclosure as a reportable segment. All other remaining operating segments did not meet the quantitative thresholds for disclosure as reportable segments.

        Information concerning revenue, results of operations and revenue by geographic area is set forth in Item 6, "Selected Financial Data," in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations," and in Note 14, "Business Segments and Major Customers," of Notes to Consolidated Financial Statements of this Form 10-K, all of which are incorporated herein by reference. Information concerning identifiable assets is also set forth in Note 14, "Business Segments and Major Customers," of Notes to Consolidated Financial Statements of this Form 10-K. Information on customers that comprise 10% or more of our consolidated revenue and risks attendant to our foreign operations is set forth below in Item 1A, "Risk Factors."

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Our Executive Officers

        Information regarding our executive officers and their ages and positions as of February 23, 2012, is contained in the table below. Our executive officers are appointed by, and serve at the discretion of, our Board of Directors. There is no family relationship between any of our executive officers.

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Item 1A.    Risk Factors

RISK FACTORS

        Because of the following factors, as well as other variables affecting our operating results, past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. See also "Special Note Regarding Forward-Looking Statements" elsewhere in this report.

Risks Associated With Our Business, Industry and Market Conditions

If market leaders do not adopt our innovations, our results of operations could decline.

        An important part of our strategy is to penetrate our target market segments by working with leaders in those market segments. This strategy is designed to encourage other participants in those segments to follow such leaders in adopting our innovations. If a high profile industry participant adopts our innovations but fails to achieve success with its products or adopts and achieves success with a competing technology, our reputation and sales could be adversely affected. In addition, some industry participants have adopted, and others may in the future adopt, a strategy of disparaging our solutions adopted by their competitors or a strategy of otherwise undermining the market adoption of our solutions.

        We target market-leading companies to adopt our technologies, particularly those that develop and market high volume business and consumer products in semiconductors, computing, tablets, handheld devices, mobile applications, gaming and graphics, high definition televisions ("HDTVs") and displays, general lighting, cryptography and data security. We have diversified our technologies through the establishment of our NBG operations and will continue to seek out other target markets in and related to computing, gaming and graphics, consumer electronics, mobile, general lighting, and security applications. We are subject to many risks beyond our control that influence whether or not a potential licensee or partner company will adopt our technologies, including, among others:

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competition faced by a company in its particular industry;



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the timely introduction and market acceptance of a company's products;



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the engineering, sales and marketing and management capabilities of a company;



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technical challenges unrelated to our innovations faced by a company in developing its products;



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the financial and other resources of a company; and



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the degree to which our licensees promote our innovations to their customers.

        There can be no assurance that consumer products that currently use our technology will continue to do so, nor can there be any assurance that the consumer products that incorporate our technology will be successful in their markets in order to generate expected royalties. If market leaders do not successfully adopt our technologies for any of these reasons, our strategy may not be successful and, as a result, our results of operations could decline.

We have traditionally operated in the semiconductor industry that is highly cyclical and in which the number of our potential customers may be in decline as a result of industry consolidation, and we face intense competition in all of our target markets that may cause our results of operations to suffer.

        The semiconductor industry is intensely competitive and has been impacted by price erosion, rapid technological change, short product life cycles and cyclical market patterns. Significant economic downturns characterized by diminished demand, erosion of average selling prices, production overcapacity and production capacity constraints can affect the highly cyclical semiconductor industry.

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The economic downturn of the past several years and the threats of further regional or worldwide downturn are evident today. As a result, we may achieve a reduced number of licenses, tightening of customers' operating budgets, difficulty or inability of our customers to pay our licensing fees, extensions of the approval process for new licenses and consolidation among our customers, all of which may adversely affect the demand for our technology and may cause us to experience substantial period-to-period fluctuations in our operating results.

        Many of our customers operate in industries that experience significant declines as a result of the recent economic downturns. In particular, DRAM manufacturers, which make up many of our existing and potential licensees, have suffered material losses and other adverse effects to their businesses. These factors may result in industry consolidation as companies seek to reduce costs and improve profitability through business combinations. Consolidation among our existing DRAM and other customers may result in loss of revenues under existing license agreements. Consolidation among companies in the DRAM and other industries within which we license our technology may reduce the number of future licensees for our products and services. In either case, consolidation in the DRAM and other industries in which we operate may negatively impact our short-term and long-term business prospects, licensing revenues and results of operations.

        We face competition from semiconductor and intellectual property companies who provide their own DDR memory chip interface technology and solutions. In addition, most DRAM manufacturers, including our XDR^TM licensees, produce versions of DRAM such as SDR, DDRx, GDDRx SDRAM and LPDDRx which compete with XDR^TM chips. We believe that our principal competition for memory chip interfaces may come from our licensees and prospective licensees, some of which are evaluating and developing products based on technologies that they contend or may contend will not require a license from us. In addition, our competitors are also taking a system approach similar to ours in seeking to solve the application needs of system companies. Many of these companies are larger and may have better access to financial, technical and other resources than we possess. Wider applications of other developing memory technologies, including FLASH memory, may also pose competition to our licensed memory solutions.

        JEDEC has standardized what it calls extensions of DDR, known as DDR2 and DDR3. Other efforts are underway to create other products including those sometimes referred to as GDDR4 and GDDR5, as well as new ways to integrate products such as system-in-package DRAM. To the extent that these alternatives might provide comparable system performance at lower or similar cost than XDR^TM memory chips, or are perceived to require the payment of no or lower royalties, or to the extent other factors influence the industry, our licensees and prospective licensees may adopt and promote alternative technologies. Even to the extent we determine that such alternative technologies infringe our patents, there can be no assurance that we would be able to negotiate agreements that would result in royalties being paid to us without litigation, which could be costly and the results of which would be uncertain.

        We also face competitive threats to our NBG operations. The display industry is intensely competitive and is impacted by rapid technological change, shifting government mandates, cyclical market patterns and increasing foreign and domestic competition. In particular, our LDT group faces competition from system and subsystem providers of backlighting and general lighting solutions, some of which have substantial resources and operations. The security technology industry also faces robust competition. Our CRI group acquired in 2011 faces competition from large semiconductor manufacturers and other companies that offer various security solutions, including hardware with on-chip security features, software based offerings and other products and services. Potential competitors may either develop their own competing offerings or acquire assets, companies or businesses that provide products or services that compete with our security technologies.

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        If for any of these reasons we cannot effectively compete in these primary markets, our results of operations could suffer.

If we do not succeed in developing our new businesses, our results of operations may be adversely affected.

        The future success of NBG, which includes our LDT, CRI and MTD groups, depends on our ability to develop new or emerging licensing opportunities, diversify our business into lighting and displays, data security, mobile communications and additional semiconductor technologies.

        For our LDT group, we will be required to improve the visual capabilities, form factor, power efficiency and cost-effectiveness of backlighting of LCD displays in products for computing, gaming and graphics, consumer electronics, mobile and general lighting applications. We will need to keep pace with rapid changes in advanced lighting and optoelectronics technology, changing consumer requirements, new product introductions and evolving industry standards, any of which could render our existing technology obsolete if we fail to respond in a timely manner. The extent to which companies in the general lighting industry adopt solid state lighting and license our lighting technologies, and the timing of such adoption and licensing, if it occurs at all, is subject to many factors beyond our control and is not predictable by us. We are subject to many risks beyond our control that influence whether or not a potential licensee or partner company will adopt and license our lighting technologies.

        For CRI, we will be required to continue to develop and provide robust data security technologies that are effective for licensees. Licensing of data security technologies also presents challenges in the face of intense competition. CRI will be required to continue to license DPA countermeasures and other security technologies, and develop new security technologies in order to grow market acceptance and revenue.

        Our MTD is another emerging business within NBG. To date, our MTD group has not generated any revenue, but our intent is to grow MTD in order to provide innovative software and technological solutions to satisfy the anticipated requirements of developers, chip suppliers and manufacturers in the market for mobile products. If the development of our MTD business does not occur, our ability to achieve success in this market may be limited, and this may in turn adversely affect our potential for long term revenue growth.

        The development, application and licensing of new technologies in lighting display, security and mobile technology is a complex process subject to a number of uncertainties, including the integration of our new businesses into the rest of our company. Our competitors have significant marketing, workforce, financial and other resources and longer operating history which could make acceptance of our lighting, data security and mobile technologies more difficult. If others develop innovative technologies that are superior to ours or if we fail to accurately anticipate technology and market trends, respond on a timely basis with our own new enhancements and technology and achieve broad market acceptance of these enhancements and technology, our competitive position may be harmed and our operating results may be adversely affected.

In order to grow, we may have to invest more resources in research and development than anticipated, which could increase our operating expenses and negatively impact our operating results.

        If new competitors, technological advances by existing competitors, our entry into new markets and/or development of new technologies or other competitive factors require us to invest significantly greater resources than anticipated in our research and development efforts, our operating expenses would increase. For the years ended December 31, 2011, 2010 and 2009, research and development expenses were $115.7 million, $92.7 million and $67.3 million, respectively, including stock-compensation of approximately $10.5 million, $10.2 million and $9.7 million, respectively. For the year ended December 31, 2011, research and development expenses also included $15.7 million for retention

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bonuses for CRI engineers who joined Rambus in June 2011. If we are required to invest significantly greater resources than anticipated in research and development efforts without an increase in revenue, our operating results could decline. Research and development expenses are likely to fluctuate from time to time to the extent we make periodic incremental investments in research and development, including as a result of our investment in new technologies. In order to grow, including entering new markets and/or developing new technologies, we anticipate that we will continue to devote substantial resources to research and development. We expect these expenses to increase in absolute dollars in the foreseeable future due to the increased complexity and the greater number of technologies under development as well as selectively hiring additional employees.

Our revenue is concentrated in a few customers, and if we lose any of these customers, our revenue may decrease substantially.

        We have a high degree of revenue concentration. Our top five licensees represented approximately 66%, 85% and 77% of our revenues for the years ended December 31, 2011, 2010 and 2009, respectively. For the years ended December 31, 2011, revenues from Elpida, NVIDIA and Samsung, each accounted for 10% or more of our revenue. For the year ended December 31, 2010, revenue from Elpida and Samsung, each accounted for 10% or more of our total revenue. For the year ended December 31, 2009, revenue from AMD, Fujitsu, NEC, Panasonic and Toshiba, each accounted for 10% or more of our total revenue. As a result of our settlement with Samsung in January 2010, Samsung accounted for a significant portion of our ongoing licensing revenue since 2010 as reflected above. We expect to continue to experience significant revenue concentration for the foreseeable future.

        In addition, some of our commercial agreements require us to provide certain customers with the lowest royalty rate that we provide to other customers for similar technologies, volumes and schedules. These clauses may limit our ability to effectively price differently among our customers, to respond quickly to market forces, or otherwise to compete on the basis of price. The particular licensees which account for revenue concentration have varied from period to period as a result of the addition of new contracts, expiration of existing contracts, renewal of existing contracts, industry consolidation, including the combination in 2010 of NEC and Renesas, and the volumes and prices at which the licensees have recently sold licensed semiconductors to system companies. These variations are expected to continue in the foreseeable future.

        We continue to be in negotiations with licensees and prospective licensees to reach patent license agreements for DRAM devices and DRAM controllers. We expect that patent license royalties will continue to vary from period to period based on our success in renewing existing license agreements and adding new licensees, as well as the level of variation in our licensees' reported shipment volumes, sales price and mix, offset in part by the proportion of licensee payments that are fixed. A number of our material license agreements are scheduled to expire in 2015. However, we cannot provide any assurance that we will reach agreement on renewal terms or that the royalty rates we will be entitled to receive under the new agreements will be as favorable to us as our current agreements. If we are unsuccessful in renewing any of these patent license agreements, our results of operations may decline significantly.

If we cannot respond to rapid technological change in our target markets by developing new innovations in a timely and cost-effective manner, our operating results will suffer.

        We derive most of our revenue from our chip interface technologies that we have patented. We expect that this dependence on our fundamental technology will continue for the foreseeable future. The semiconductor industry is characterized by rapid technological change, with new generations of semiconductors being introduced periodically and with ongoing improvements. The introduction or market acceptance of competing chip interfaces that render our chip interfaces less desirable or

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obsolete would have a rapid and material adverse effect on our business, results of operations and financial condition. The announcement of new chip interfaces by us could cause licensees or system companies to delay or defer entering into arrangements for the use of our current chip interfaces, which could have a material adverse effect on our business, financial condition and results of operations.

        Our success depends on our ability to introduce and patent enhancements and new generations of our chip interface technologies that keep pace with other changes in the semiconductor industry and which achieve rapid market acceptance. We must devote significant engineering resources to addressing the need for higher speed chip interfaces associated with increases in the speed of microprocessors and other controllers. The technical innovations that are required for us to be successful are inherently complex and require long development cycles, and there can be no assurance that our development efforts will ultimately be successful. In addition, these innovations must be:

•

completed before changes in the semiconductor industry render them obsolete;



•

available when system companies require these innovations; and



•

sufficiently compelling to cause semiconductor manufacturers to enter into licensing arrangements with us to implement these new technologies.

        In all of our target markets, significant technological innovations generally require a substantial investment before their commercial viability can be determined. There can be no assurance that we have accurately estimated the amount of resources required to complete our innovation efforts, or that we will have, or be able to expend, sufficient resources required for the development of our innovations. In addition, there is market risk associated with these products for which we develop technological innovations, and there can be no assurance that unit volumes, and their associated royalties, will occur. If our technology fails to capture or maintain a portion of the high volume target consumer market, our business results could suffer.

Security breaches or vulnerabilities in our data security technologies could harm our reputation, result in financial losses and divert resources.

        Because the techniques used by hackers to access or sabotage secure chip and other technologies change frequently and generally are not recognized until launched against a target, we may be unable to anticipate these techniques and may not address them in our CRI data security technologies. Furthermore, our data security technologies may also fail to detect or prevent security breaches due to a number of reasons such as the evolving nature of such threats and the continual emergence of new threats. An actual or perceived security breach of our licensees or their end-customers, regardless of whether the breach is attributable to the failure of our data security technologies, could adversely affect the market's perception of our security technologies. We may not be able to correct any security flaws or vulnerabilities promptly, or at all. Any breaches, defects, errors or vulnerabilities in our data security technologies could result in:

•

expenditure of significant financial and research and development resources in efforts to analyze, correct, eliminate or work-around breaches, errors or defects or to address and eliminate vulnerabilities;



•

financial liability to licensees for breach of certain contract provisions;



•

loss of existing or potential licensees;



•

delayed or lost revenue;



•

delay or failure to attain market acceptance;



•

negative publicity, which will harm our reputation; and

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•

litigation, regulatory inquiries or investigations that may be costly and harm our reputation.

We have in the past and may in the future make acquisitions or enter into mergers, strategic transactions or other arrangements that may or may not produce the expected operating and financial results.

        As part of our strategic initiatives, we currently are evaluating, and expect to continue to engage in, investments in or acquisitions of companies, products, patents or technologies, and the entry into strategic transactions or other arrangements. We completed a number of acquisitions in 2009, 2010 and 2011, including the acquisition of CRI, our largest transaction to date. These acquisitions, investments, transactions or arrangements are likely to range in size, some of which may be significant. After completing our acquisitions, we may experience difficulty integrating personnel and operations, which could negatively affect our operating results. In addition:

•

the key personnel of the acquired entity or business may decide not to work for us or may not perform according to our expectations;



•

we may experience additional legal, financial and accounting challenges and complexities in areas such as licensing, tax planning, cash management and financial reporting;



•

we may experience challenges with existing or prospective licensees as a result of potential conflict between pre-existing and historical relationships and any newly acquired engagements and agreements;



•

our ongoing business, including our operations, technology development and deliveries to our customers, may be disrupted, and employee retention and productivity could also suffer;



•

we may not be able to recognize the financial benefits we anticipated and/or we may suffer losses, both with respect to our ongoing business and the acquired entity or business;



•

our increasing international presence resulting from acquisitions may increase our exposure to international currency, tax and political risks; and



•

our lack of experience with new products or technologies in new markets may cause us to fail to achieve expected financial and strategic benefits of the acquisition.

        In connection with our strategic initiatives related to future acquisitions or mergers, strategic transactions or other arrangements, we may incur substantial expenses regardless of whether any transactions occur. Further, the risks described above may be exacerbated as a result of managing multiple acquisitions simultaneously.

        In addition, we may be required to assume the liabilities of the companies or related to the businesses we acquire. The assumption of such liabilities may include those related to intellectual property infringement or indemnification of customers of acquired businesses for similar claims, which could materially and adversely affect our business.

        We may have to incur debt or issue equity securities to pay for any future acquisition, which debt or equity securities could involve restrictive covenants or be dilutive to our existing stockholders.

Some of our revenue is subject to the pricing policies of our licensees over whom we have no control.

        We have no control over our licensees' pricing of their products and there can be no assurance that licensee products using or containing our chip interfaces will be competitively priced or will sell in significant volumes. One important requirement for our memory chip interfaces is for any premium charged by our licensees in the price of memory and controller chips over alternatives to be reasonable in comparison to the perceived benefits of the chip interfaces. If the benefits of our technology do not match the price premium charged by our licensees, the resulting decline in sales of products incorporating our technology could harm our operating results.

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Our licensing cycle is lengthy and costly, and our marketing and licensing efforts may be unsuccessful.

        The process of persuading customers to adopt and license our chip interface, lighting and display, data security, mobile and other semiconductor technologies can be lengthy and, even if successful, there can be no assurance that our technologies will be used in a product that is ultimately brought to market, achieves commercial acceptance or results in significant royalties to us. We generally incur significant marketing and sales expenses prior to entering into our license agreements, generating a license fee and establishing a royalty stream from each licensee. The length of time it takes to establish a new licensing relationship can take many months or even years. In addition, our ongoing intellectual property litigation and regulatory actions have and will likely continue to have an impact on our ability to enter into new licenses and renewals of licenses. We may incur costs in any particular period before any associated revenue stream begins, if at all. If our marketing and sales efforts are very lengthy or unsuccessful, then we may face a material adverse effect on our business and results of operations as a result of failure or delay to obtain royalties.

Future revenue is difficult to predict for several reasons, and our failure to predict revenue accurately may cause us to miss analysts' estimates and result in our stock price declining.

        Our lengthy and costly license negotiation cycle and our ongoing intellectual property litigation make our future revenue difficult to predict because we may not be successful in entering into licenses with our customers on our estimated timelines and we are reliant on the litigation timelines for any results or settlements.

        While some of our license agreements provide for fixed, quarterly royalty payments, many of our license agreements provide for volume-based royalties, and may also be subject to caps on royalties in a given period. The sales volume and prices of our licensees' products in any given period can be difficult to predict. As a result, our actual results may differ substantially from analyst estimates or our forecasts in any given quarter.

        In addition, a portion of our revenue comes from development and support services provided to our licensees. Depending upon the nature of the services, a portion of the related revenue may be recognized ratably over the support period, or may be recognized according to contract accounting. Contract revenue accounting may result in deferral of the service fees to the completion of the contract, or may be recognized over the period in which services are performed on a percentage-of-completion basis. There can be no assurance that the product development schedule for these projects will not be changed or delayed.

        All of these factors make it difficult to predict future revenue and may result in our missing previously announced earnings guidance or analysts' estimates which would likely cause our stock price to decline.

A substantial portion of our revenue is derived from sources outside of the United States and this revenue and our business generally are subject to risks related to international operations that are often beyond our control.

        For the years ended December 31, 2011, 2010 and 2009, revenue received from our international customers constituted approximately 67%, 93% and 83%, respectively, of our total revenue. As a result of our continued focus on international markets, we expect that future revenue derived from international sources will continue to represent a significant portion of our total revenue.

        To date, all of the revenue from international licensees has been denominated in U.S. dollars. However, to the extent that such licensees' sales to systems companies are not denominated in U.S. dollars, any royalties which are based as a percentage of the customer's sales that we receive as a result of such sales could be subject to fluctuations in currency exchange rates. In addition, if the effective

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price of licensed semiconductors sold by our foreign licensees were to increase as a result of fluctuations in the exchange rate of the relevant currencies, demand for licensed semiconductors could fall, which in turn would reduce our royalties. We do not use financial instruments to hedge foreign exchange rate risk.

        We currently have international design operations in India and business development operations in Japan, Korea, Taiwan and Germany. Our international operations and revenue are subject to a variety of risks which are beyond our control, including:

•

export controls, tariffs, import and licensing restrictions and other trade barriers;



•

profits, if any, earned abroad being subject to local tax laws and not being repatriated to the United States or, if repatriation is possible, limited in amount;



•

treatment of revenue from international sources and changes to tax codes, including being subject to foreign tax laws and being liable for paying withholding, income or other taxes in foreign jurisdictions, such as withholding taxes in Korea;



•

foreign government regulations and changes in these regulations;



•

lack of protection of our intellectual property and other contract rights by jurisdictions in which we may do business to the same extent as the laws of the United States;



•

hiring, maintaining and managing a workforce remotely and under various legal systems;



•

natural disasters, acts of war, terrorism, widespread illness or securities breaches;



•

social, political and economic instability;



•

geo-political issues; including changes in diplomatic and trade relationships; and



•

cultural differences in the conduct of business both with licensees and in conducting business in our international facilities and international sales offices.

        We and our licensees are subject to many of the risks described above with respect to companies which are located in different countries, particularly home video game console, PC and other consumer electronics manufacturers located in Asia and elsewhere. There can be no assurance that one or more of the risks associated with our international operations will not result in a material adverse effect on our business, financial condition or results of operations.

Weak global economic conditions may adversely affect demand for the products and services of our licensees.

        Our operations and performance depend significantly on worldwide economic conditions, and the U.S. and world economies have experienced a prolonged period of weak economic conditions, and the threats of further regional or worldwide downturn are evident today. Uncertainty about global economic conditions poses a risk as consumers and businesses may postpone spending in response to tighter credit, negative financial news and declines in income or asset values, which could have a material negative effect on the demand for the products of our licensees in the foreseeable future. Other factors that could influence demand include continuing increases in fuel and energy costs, competitive pressures, including pricing pressures, from companies that have competing products, changes in the credit market, conditions in the residential real estate and mortgage markets, consumer confidence, and other macroeconomic factors affecting consumer spending behavior. If our licensees experience reduced demand for their products as a result of economic conditions or otherwise, our business and results of operations could be harmed.

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If our counterparties are unable to fulfill their financial and other obligations to us, our business and results of operations may be affected adversely.

        Any downturn in economic conditions or other business factors could threaten the financial health of our counterparties, including companies with whom we have entered into licensing arrangements, settlement agreements or that have been subject to litigation judgments that provide for payments to us, and their ability to fulfill their financial and other obligations to us. Such financial pressures on our counterparties may eventually lead to bankruptcy proceedings or other attempts to avoid financial obligations that are due to us under licenses, settlement agreements or litigation judgments. Because bankruptcy courts have the power to modify or cancel contracts of the petitioner which remain subject to future performance and alter or discharge payment obligations related to pre-petition debts, we may receive less than all of the payments that we would otherwise be entitled to receive from any such counterparty as a result of a bankruptcy proceedings. For example, in 2009, two of our counterparties, Qimonda and Spansion, were subject to insolvency proceedings in their applicable jurisdictions as a result of a downturn in business which led to lower than anticipated or no payment to us. If we are unable to collect all of such payments owed to us, or if other of our counterparties enter into bankruptcy or otherwise seek to renegotiate their financial obligations to us as a result of the deterioration of their financial health, our business and results of operations may be affected adversely.

If we are unable to attract and retain qualified personnel, our business and operations could suffer.

        Our success is dependent upon our ability to identify, attract, compensate, motivate and retain qualified personnel, especially engineers, who can enhance our existing technologies and introduce new technologies. Competition for qualified personnel, particularly those with significant industry experience, is intense, in particular in the San Francisco Bay Area where we are headquartered and in the area of Bangalore, India where we have a design center. We are also dependent upon our senior management personnel. The loss of the services of any of our senior management personnel, or key sales personnel in critical markets, or critical members of staff, or of a significant number of our engineers could be disruptive to our development efforts or business relationships and could cause our business and operations to suffer.

We are subject to government restrictions and regulation, including on the sale of products and services that use encryption technology.

        Various countries have adopted controls, license requirements and restrictions on the export, import and use of products or services that contain encryption technology. In addition, from time to time, governmental agencies have proposed additional requirements for encryption technology, such as requiring the escrow and governmental recovery of private encryption keys. Restrictions on the sale or distribution of products or services containing encryption technology may impact the ability of CRI to license its data security technologies to the manufacturers and providers of such products and services in certain markets or may require CRI or its licensees to make changes to the licensed data security technology that is embedded in such products to comply with such restrictions. Government restrictions, or changes to the products or services of CRI licensees to comply with such restrictions, could delay or prevent the acceptance and use of such licensees' products and services. In addition, the United States and other countries have imposed export controls that prohibit the export of encryption technology to certain countries, entities and individuals. Our failure to comply with export and use regulations concerning encryption technology of CRI could subject us to sanctions and penalties, including fines, and suspension or revocation of export or import privileges. Regulatory initiatives throughout the world can also create new and unforeseen regulatory obligations on us and the technology we develop, particularly for CRI. The impact of these potential obligations varies based on the jurisdiction, but any such changes could impact whether we enter, maintain or expand our presence in a particular market or with particular potential licensees.

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Our operations are subject to risks of natural disasters, acts of war, terrorism, widespread illness or security breach at our domestic and international locations, any one of which could result in a business stoppage and negatively affect our operating results.

        Our business operations depend on our ability to maintain and protect our facilities, computer systems and personnel, which are primarily located in the San Francisco Bay Area. The San Francisco Bay Area is in close proximity to known earthquake fault zones. Our facilities and transportation for our employees are susceptible to damage from earthquakes and other natural disasters such as fires, floods and similar events. Should a catastrophe disable our facilities, we do not have readily available alternative facilities from which we could conduct our business, which stoppage could have a negative effect on our operating results. We also rely on our network infrastructure and technology systems for operational support and business activities, which are subject to damage from malicious code and other related vulnerabilities common to networks and computer systems, including acts of vandalism and potential security breach by third parties. Acts of terrorism, widespread illness, war and any event that causes failures or interruption in our network infrastructure and technology systems could have a negative effect at our international and domestic facilities and could harm our business, financial condition, and operating results.

Unanticipated changes in our tax rates or in the tax laws and regulations could expose us to additional income tax liabilities which could affect our operating results and financial condition.

        We are subject to income taxes in both the United States and various foreign jurisdictions. Significant judgment is required in determining our worldwide provision (or benefit) for income taxes and, in the ordinary course of business, there are many transactions and calculations where the ultimate tax determination is uncertain. Our effective tax rate could be adversely affected by changes in the mix of earnings in countries with differing statutory tax rates, changes in the valuation of deferred tax assets and liabilities, changes in tax laws and regulations as well as other factors. Our tax determinations are regularly subject to audit by tax authorities and developments in those audits could adversely affect our income tax provision. Although we believe that our tax estimates are reasonable, the final determination of tax audits or tax disputes may be different from what is reflected in our historical income tax provisions which could affect our operating results.

Our results of operations could vary as a result of the methods, estimates and judgments we use in applying our accounting policies.

        The methods, estimates and judgments we use in applying our accounting policies have a significant impact on our results of operations, including the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities, as described elsewhere in this report. On an ongoing basis, we evaluate our estimates, including those related to revenue recognition, investments, income taxes, litigation, goodwill and intangibles, and other contingencies. Such methods, estimates and judgments are, by their nature, subject to substantial risks, uncertainties and assumptions, and factors may arise over time that lead us to change our methods, estimates and judgments. In addition, actual results may differ from these estimates under different assumptions or conditions.

        Changes in those methods, estimates and judgments could significantly affect our results of operations. In particular, the measurement of share-based compensation expense requires us to use valuation methodologies and a number of assumptions, estimates and conclusions regarding matters such as expected forfeitures, expected volatility of our share price, and the exercise behavior of our employees. Changes in these factors may affect both our reported results (including cost of contract revenue, research and development expenses, marketing, general and administrative expenses and our effective tax rate) and any forward-looking projections we make that incorporate projections of share-based compensation expense. Furthermore, there are no means, under applicable accounting principles,

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to compare and adjust our reported expense if and when we learn about additional information that may affect the estimates that we previously made, with the exception of changes in expected forfeitures of share-based awards.

        Factors may arise that lead us to change our estimates and assumptions with respect to future share-based compensation arrangements, resulting in variability in our share-based compensation expense over time.

Risks Related to Capitalization Matters and Corporate Governance

The price of our common stock may fluctuate significantly, which may make it difficult for holders to resell their shares when desired or at attractive prices.

        Our common stock is listed on The NASDAQ Global Select Market under the symbol "RMBS." The trading price of our common stock has been subject to wide fluctuations which we expect to continue in the future in response to, among other things, the following:

•

new litigation or developments in current litigation, including an unfavorable outcome to us from court proceedings relating to our ongoing litigation and reaction to any settlements that we enter into with former litigants, such as the November 2011 verdict against us in our San Francisco antitrust proceeding, and the unpredictability of litigation results or settlements and the timing and amount of any litigation expenses;



•

any progress, or lack of progress, real or perceived, in the development of products that incorporate our innovations and technology companies' acceptance of our products, including the results of our efforts to expand into new target markets;



•

our signing or not signing new licensees and the loss of strategic relationships with any licensee;



•

the success of high volume consumer applications;



•

the dependence of our royalties upon fluctuating sales volumes and prices of products that include our technology, including the seasonal shipment patterns of systems incorporating our products and semiconductor or system companies discontinuing major products incorporating our products;



•

announcements of our technological innovations or new products by us, our licensees or our competitors;



•

changes in our customers' development schedules and levels of expenditure on research and development;



•

our licensees terminating or failing to make payments under their current contracts or seeking to modify such contracts, whether voluntarily or as a result of financial difficulties;



•

changes in our strategies, including changes in our licensing focus and/or acquisitions of companies with business models or target markets different from our own;



•

changes in the economy and credit market and their effects upon demand for our technology and the products of our licensees;



•

positive or negative reports by securities analysts as to our expected financial results and business developments;



•

developments with respect to patents or proprietary rights and other events or factors;



•

trading activity related to our share repurchase plans; and



•

issuance of additional securities by us, including in acquisitions.

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        In addition, the stock market in general, and prices for companies in our industry in particular, have experienced extreme volatility that often has been unrelated to the operating performance of such companies. These broad market and industry fluctuations may adversely affect the price of our common stock, regardless of our operating performance.

        Because our outstanding senior convertible notes are convertible into shares of our common stock, volatility or depressed prices of our common stock could have a similar effect on the trading price of our notes. In addition, the existence of the notes may encourage short selling in our common stock by market participants because the conversion of the notes could depress the price of our common stock.

        Sales of substantial amounts of shares of our common stock in the public market, or the perception that those sales may occur, could cause the market price of our common stock to decline. In addition, lack of positive performance in our stock price may adversely affect our ability to retain key employees.

We have been party to, and may in the future be subject to, lawsuits relating to securities law matters which may result in unfavorable outcomes and significant judgments, settlements and legal expenses which could cause our business, financial condition and results of operations to suffer.

        In connection with our stock option investigation, we and certain of our current and former officers and directors, as well as our current auditors, were subject to several stockholder derivative actions, securities fraud class actions and/or individual lawsuits filed in federal court against us and certain of our current and former officers and directors. The complaints generally allege that the defendants violated the federal and state securities laws and state law claims for fraud and breach of fiduciary duty. While we have settled most of these actions, certain individual lawsuits continue to be adjudicated. For more information about the historic litigation described above, see Note 16, "Litigation and Asserted Claims," of Notes Consolidated Financial Statements contained in this Form 10-K. The amount of time to resolve these current and any future lawsuits is uncertain, and these matters could require significant management and financial resources which could otherwise be devoted to the operation of our business. Although we have expensed or accrued for certain liabilities that we believe will result from certain of these actions, the actual costs and expenses to defend and satisfy all of these lawsuits and any potential future litigation may exceed our current estimated accruals, possibly significantly. Unfavorable outcomes and significant judgments, settlements and legal expenses in litigation related to our past and any future securities law claims could have material adverse impacts on our business, financial condition, results of operations, cash flows and the trading price of our common stock.

We are leveraged financially, which could adversely affect our ability to adjust our business to respond to competitive pressures and to obtain sufficient funds to satisfy our future research and development needs, to protect and enforce our intellectual property and other needs.

        We have indebtedness. In 2009, we issued $172.5 million aggregate principal amount of our 2014 Notes. The degree to which we are leveraged could have important consequences, including, but not limited to, the following:

•

our ability to obtain additional financing in the future for working capital, capital expenditures, acquisitions, litigation, general corporate or other purposes may be limited;



•

a substantial portion of our cash flows from operations in the future will be dedicated to the payment of the principal of our indebtedness as we are required to pay the principal amount of our 2014 Notes in cash upon conversion if specified conditions are met or when due;

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•

if upon any conversion of our 2014 Notes we are required to satisfy our conversion obligation with shares of our common stock or we are required to pay a "make-whole" premium with shares of our common stock, our existing stockholders' interest in us would be diluted; and



•

we may be more vulnerable to economic downturns, less able to withstand competitive pressures and less flexible in responding to changing business and economic conditions.

        A failure to comply with the covenants and other provisions of our debt instruments could result in events of default under such instruments, which could permit acceleration of all of our notes. Any required repayment of our notes as a result of a fundamental change or other acceleration would lower our current cash on hand such that we would not have those funds available for use in our business.

        If we are at any time unable to generate sufficient cash flows from operations to service our indebtedness when payment is due, we may be required to attempt to renegotiate the terms of the instruments relating to the indebtedness, seek to refinance all or a portion of the indebtedness or obtain additional financing. There can be no assurance that we will be able to successfully renegotiate such terms, that any such refinancing would be possible or that any additional financing could be obtained on terms that are favorable or acceptable to us.

If securities or industry analysts change their recommendations regarding our stock adversely, our stock price and trading volume could decline.

        The trading market for our common stock is influenced by the research and reports that industry or securities analysts publish about us, our business or our market. If one or more of the analysts who cover us change their recommendation regarding our stock adversely, our stock price would likely decline. If one or more of these analysts ceases coverage of our company or fails to regularly publish reports on us, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline.

Compliance with changing regulation of corporate governance and public disclosure may result in additional expenses.

        Changing laws, regulations and standards relating to corporate governance and public disclosure, including the historic Sarbanes-Oxley Act and recent Dodd-Frank Act, and new Securities and Exchange Commission regulations and NASDAQ rules, have historically created uncertainty for companies such as ours. Any new or changed laws, regulations and standards are subject to varying interpretations in many cases due to their lack of specificity, and as a result, their application in practice may evolve over time as new guidance is provided by regulatory and governing bodies, which could result in continuing uncertainty regarding compliance matters and higher costs necessitated by ongoing revisions to disclosure and governance practices. Any new investment of resources to comply with evolving laws, regulations and standards, may result in increased general and administrative expenses and a diversion of management time and attention from revenue generating activities to compliance activities. If our efforts to comply with new or changed laws, regulations and standards differ from the activities intended by regulatory or governing bodies due to ambiguities related to practice, our reputation may be harmed and our business and operations would suffer.

Our restated certificate of incorporation and bylaws, Delaware law and our outstanding convertible notes contain provisions that could discourage transactions resulting in a change in control, which may negatively affect the market price of our common stock.

        Our restated certificate of incorporation, our bylaws and Delaware law contain provisions that might enable our management to discourage, delay or prevent a change in control. In addition, these

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provisions could limit the price that investors would be willing to pay in the future for shares of our common stock. Pursuant to such provisions:

•

our board of directors is authorized, without prior stockholder approval, to create and issue preferred stock, commonly referred to as "blank check" preferred stock, with rights senior to those of common stock, which means that a new stockholder rights plan could be implemented by our board to replace our old plan that expired in 2010;



•

our board of directors is staggered into two classes, only one of which is elected at each annual meeting;



•

stockholder action by written consent is prohibited;



•

nominations for election to our board of directors and the submission of matters to be acted upon by stockholders at a meeting are subject to advance notice requirements;



•

certain provisions in our bylaws and certificate of incorporation such as notice to stockholders, the ability to call a stockholder meeting, advance notice requirements and action of stockholders by written consent may only be amended with the approval of stockholders holding 66²/3% of our outstanding voting stock;



•

our stockholders have no authority to call special meetings of stockholders; and



•

our board of directors is expressly authorized to make, alter or repeal our bylaws.

        We are also subject to Section 203 of the Delaware General Corporation Law, which provides, subject to enumerated exceptions, that if a person acquires 15% or more of our outstanding voting stock, the person is an "interested stockholder" and may not engage in any "business combination" with us for a period of three years from the time the person acquired 15% or more of our outstanding voting stock.

        Certain provisions of our outstanding convertible notes could make it more difficult or more expensive for a third party to acquire us. Upon the occurrence of certain transactions constituting a fundamental change, holders of the notes will have the right, at their option, to require us to repurchase, at a cash repurchase price equal to 100% of the principal amount plus accrued and unpaid interest on the notes, all or a portion of their notes. We may also be required to issue additional shares of our common stock upon conversion of such notes in the event of certain fundamental changes.

Litigation, Regulation and Business Risks Related to our Intellectual Property

We face current and potential adverse determinations in litigation stemming from our efforts to protect and enforce our patents and intellectual property and make other claims, which could broadly impact our intellectual property rights, distract our management and cause substantial expenses and declines in our revenue and stock price.

        We seek to diligently protect our intellectual property rights. In connection with the extension of our licensing program to SDR SDRAM-compatible and DDR SDRAM-compatible products, we became involved in litigation related to such efforts against different parties in multiple jurisdictions. In each of these cases, we have claimed infringement of certain of our patents, while the manufacturers of such products have generally sought damages and a determination that the patents in suit are invalid, unenforceable and not infringed. Among other things, the opposing parties have alleged that certain of our patents are unenforceable because we engaged in document spoliation, litigation misconduct and/or acted improperly during our 1991 to 1995 participation in the JEDEC standard setting organization (including allegations of antitrust violations and unfair competition). We have also become involved in litigation related to infringement of our patents related to products having certain peripheral interfaces. In addition, we did not prevail at jury trial in our antitrust suit against certain memory manufacturers

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in November 2011, which caused the market price of our stock to drop significantly, and we face appeals and further proceedings related to such actions. See Note 16, "Litigation and Asserted Claims," of Notes to Consolidated Financial Statements of this Form 10-K.

        There can be no assurance that any or all of the opposing parties will not succeed, either at the trial or appellate level, with such claims or counterclaims against us or that they will not in some other way establish broad defenses against our patents, achieve conflicting results or otherwise avoid, delay paying royalties for the use of our patented technology, or obtain orders to require us to pay or reimburse their costs or attorneys' fees in material amounts or post bonds to cover such amounts. Moreover, there is a risk that if one party prevails against us, other parties could use the adverse result to defeat or limit our claims against them; conversely, there can be no assurance that if we prevail against one party, we will succeed against other parties on similar claims, defenses, or counterclaims. In addition, there is the risk that the pending litigations and other circumstances may cause us to accept less than what we now believe to be fair consideration in settlement.

        Any of these matters or any future intellectual property litigation, whether or not determined in our favor or settled by us, is costly, may cause delays (including delays in negotiating licenses with other actual or potential licensees), will tend to discourage future design partners, will tend to impair adoption of our existing technologies and divert the efforts and attention of our management and technical personnel from other business operations. In addition, we may be unsuccessful in our litigation if we have difficulty obtaining the cooperation of former employees and agents who were involved in our business during the relevant periods related to our litigation and are now needed to assist in cases or testify on our behalf. Furthermore, any adverse determination or other resolution in litigation could result in our losing certain rights beyond the rights at issue in a particular case, including, among other things: our being effectively barred from suing others for violating certain or all of our intellectual property rights; our patents being held invalid or unenforceable or not infringed; our being subjected to significant liabilities; our being required to seek licenses from third parties; our being prevented from licensing our patented technology; or our being required to renegotiate with current licensees on a temporary or permanent basis.

        Even if we are successful in our litigation, or any settlement of such litigation, there is no guarantee that the applicable opposing parties will be able to pay any damages awards timely or at all as a result of financial difficulties or otherwise. Delay or any or all of these adverse results could cause substantial expenses or declines in our revenue and stock price.

From time to time, we are subject to proceedings by government agencies, such as our Federal Trade Commission and European Commission proceedings over the past several years. These proceedings may result in adverse determinations against us or in other outcomes that could limit our ability to enforce or license our intellectual property, and could cause our revenue to decline substantially.

        An adverse resolution by or with a governmental agency could result in severe limitations on our ability to protect and license our intellectual property, and would cause our revenue to decline substantially.

        Third parties have and may attempt to use adverse findings by a government agency to limit our ability to enforce or license our patents in private litigations, to challenge or otherwise act against us with respect to such government agency proceedings, such as the attempts by Hynix to appeal our settlement with the European Commission and to assert claims for monetary damages against us, and other attempts by other adverse parties to challenge our settlement. Although we have successfully defeated certain attempts to do so, there can be no assurance that other third parties will not be successful in the future or that additional claims or actions arising out of adverse findings by a government agency will not be asserted against us.

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        Further, third parties have sought and may seek review and reconsideration of the patentability of inventions claimed in certain of our patents by the U.S. Patent and Trademark Office ("PTO") and/or the European Patent Office (the "EPO"). Currently, we are subject to numerous re-examination proceedings, including proceedings initiated by Hynix, Micron and NVIDIA as a defensive action in connection with our litigation against those companies. A number of these re-examination proceedings are being reviewed by the PTO's Board of Patent Appeals and Interferences ("BPAI"). The BPAI has issued decisions in a few cases, finding the challenged claims of Rambus's patents to be invalid. Decisions of the BPAI are subject to further PTO proceedings and appeal to the Court of Appeals for the Federal Circuit. A final adverse decision by the PTO or EPO could invalidate some or all of these patent claims and could also result in additional adverse consequences affecting other related U.S. or European patents, including in our intellectual property litigation. If a sufficient number of such patents are impaired, our ability to enforce or license our intellectual property would be significantly weakened and this could cause our revenue to decline substantially.

        The pendency of any governmental agency acting as described above may impair our ability to enforce or license our patents or collect royalties from existing or potential licensees, as our litigation opponents may attempt to use such proceedings to delay or otherwise impair any pending cases and our existing or potential licensees may await the final outcome of any proceedings before agreeing to new licenses or pay royalties.

Litigation or other third-party claims of intellectual property infringement could require us to expend substantial resources and could prevent us from developing or licensing our technology on a cost-effective basis.

        Our research and development programs are in highly competitive fields in which numerous third parties have issued patents and patent applications with claims closely related to the subject matter of our programs. We have also been named in the past, and may in the future be named, as a defendant in lawsuits claiming that our technology infringes upon the intellectual property rights of third parties. As we develop additional products and technology, we may face claims of infringement of various patents and other intellectual property rights by third parties. In the event of a third-party claim or a successful infringement action against us, we may be required to pay substantial damages, to stop developing and licensing our infringing technology, to develop non-infringing technology, and to obtain licenses, which could result in our paying substantial royalties or our granting of cross licenses to our technologies. Threatened or ongoing third-party claims of infringement actions may prevent us from pursuing additional development and licensing arrangements for some period. For example, we may discontinue negotiations with certain customers for additional licensing of our patents due to the uncertainty caused by our ongoing litigation on the terms of such licenses or of the terms of such licenses on our litigation. We may not be able to obtain licenses from other parties at a reasonable cost, or at all, which could cause us to expend substantial resources, or result in delays in, or the cancellation of, new product.

If we are unable to successfully protect our inventions through the issuance and enforcement of patents, our operating results could be adversely affected.

        We have an active program to protect our proprietary inventions through the filing of patents. There can be no assurance, however, that:

•

any current or future U.S. or foreign patent applications will be approved and not be challenged by third parties;



•

our issued patents will protect our intellectual property and not be challenged by third parties;



•

the validity of our patents will be upheld;

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•

our patents will not be declared unenforceable;



•

the patents of others will not have an adverse effect on our ability to do business;



•

Congress or the U.S. courts or foreign countries will not change the nature or scope of rights afforded patents or patent owners or alter in an adverse way the process for seeking or enforcing patents;



•

changes in law will not be implemented, or changes in interpretation of such laws will occur, that will affect our ability to protect and enforce our patents and other intellectual property, including as a result of the 2011 passage of the America Invents Act of 2011 (which codifies several significant changes to the U.S. patent laws and will remain subject to certain rule-making and interpretation, including changing from a "first to invent" to a "first inventor to file" system, limiting where a patentee may file a patent suit, requiring the apportionment of patent damages, replacing interference proceedings with derivation actions, and creating a post-grant opposition process to challenge patents after they have issued);



•

new legal theories and strategies utilized by our competitors will not be successful;



•

others will not independently develop similar or competing chip interfaces or design around any patents that may be issued to us; or



•

factors such as difficulty in obtaining cooperation from inventors, pre-existing challenges or litigation, or license or other contract issues will not present additional challenges in securing protection with respect to patents and other intellectual property that we acquire.

        If any of the above were to occur, our operating results could be adversely affected.

        In addition, our patents will continue to expire according to their terms, with expiration dates ranging from 2012 to 2030. Our failure to continuously develop or acquire successful innovations and obtain patents on those innovations could significantly harm our business, financial condition, results of operations, or cash flows.

Our inability to protect and own the intellectual property we create would cause our business to suffer.

        We rely primarily on a combination of license, development and nondisclosure agreements, trademark, trade secret and copyright law and contractual provisions to protect our non-patentable intellectual property rights. If we fail to protect these intellectual property rights, our licensees and others may seek to use our technology without the payment of license fees and royalties, which could weaken our competitive position, reduce our operating results and increase the likelihood of costly litigation. The growth of our business depends in large part on the use of our intellectual property in the products of third party manufacturers, and our ability to enforce intellectual property rights against them to obtain appropriate compensation. In addition, effective trade secret protection may be unavailable or limited in certain foreign countries. Although we intend to protect our rights vigorously, if we fail to do so, our business will suffer.

We rely upon the accuracy of our licensees' recordkeeping, and any inaccuracies or payment disputes for amounts owed to us under our licensing agreements may harm our results of operations.

        Many of our license agreements require our licensees to document the manufacture and sale of products that incorporate our technology and report this data to us on a quarterly basis. While licenses with such terms give us the right to audit books and records of our licensees to verify this information, audits rarely are undertaken because they can be expensive, time consuming, and potentially detrimental to our ongoing business relationship with our licensees. Therefore, we typically rely on the accuracy of the reports from licensees without independently verifying the information in them. Our failure to audit our licensees' books and records may result in our receiving more or less royalty

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revenue than we are entitled to under the terms of our license agreements. If we conduct royalty audits in the future, such audits may trigger disagreements over contract terms with our licensees and such disagreements could hamper customer relations, divert the efforts and attention of our management from normal operations and impact our business operations and financial condition.

Any dispute regarding our intellectual property may require us to indemnify certain licensees, the cost of which could severely hamper our business operations and financial condition.

        In any potential dispute involving our patents or other intellectual property, our licensees could also become the target of litigation. While we generally do not indemnify our licensees, some of our license agreements provide limited indemnities, and some require us to provide technical support and information to a licensee that is involved in litigation involving use of our technology. In addition, we may agree to indemnify others in the future. Any of these indemnification and support obligations could result in substantial expenses. In addition to the time and expense required for us to indemnify or supply such support to our licensees, a licensee's development, marketing and sales of licensed semiconductors, lighting and display, mobile communications and data security technologies could be severely disrupted or shut down as a result of litigation, which in turn could severely hamper our business operations and financial condition as a result of lower or no royalty payments.

Item 1B.    Unresolved Staff Comments

        None.

Item 2.    Properties

        As of December 31, 2011, we occupied offices in the leased facilities described below:

Item 3.    Legal Proceedings

        For the information required by this item regarding legal proceedings, see Note 16 "Litigation and Asserted Claims," of Notes to Consolidated Financial Statements of this Form 10-K.

Item 4.    Mine Safety Disclosures

        Not applicable.

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PART II

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

        Our Common Stock is listed on The NASDAQ Global Select Market under the symbol "RMBS." The following table sets forth for the periods indicated the high and low sales price per share of our Common Stock as reported on The NASDAQ Global Select Market.

        The graph below compares the cumulative 5-year total return of holders of Rambus Inc.'s common stock with the cumulative total returns of the NASDAQ Composite index and the RDG Semiconductor Composite index. The graph tracks the performance of a $100 investment in our common stock and in each of the indexes (with the reinvestment of all dividends) from December 31, 2006 to December 31, 2011.

COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*
Among Rambus Inc., the NASDAQ Composite Index,
and the RDG Semiconductor Composite Index

*

$100 invested on 12/31/06 in stock or index, including reinvestment of dividends.
Fiscal year ending December 31.

        Fiscal years ending:

        The stock price performance included in this graph is not necessarily indicative of future stock price performance.

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        Information regarding our securities authorized for issuance under equity compensation plans will be included in Item 12, "Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters," of this report on Form 10-K.

        As of January 31, 2012, there were 695 holders of record of our Common Stock. Since many of the shares of our Common Stock are held by brokers and other institutions on behalf of stockholders, we are unable to estimate the total number of beneficial stockholders represented by these record holders.

        We have never paid or declared any cash dividends on our Common Stock or other securities.

Contingently Redeemable Common Stock

        On January 19, 2010, pursuant to the terms of the Stock Purchase Agreement, Samsung purchased for cash from us 9.6 million shares of our common stock (the "Shares") with certain restrictions and put rights. The issuance of the Shares by us to Samsung was made through a private transaction. The Stock Purchase Agreement provided Samsung a one-time put right, beginning 18 months after the date of the Stock Purchase Agreement and extending to 19 months after the date of the Stock Purchase Agreement, to put back to us up to 4.8 million of the Shares at the original issue price of $20.885 per share (for an aggregate purchase price of up to $100.0 million). The 4.8 million shares were recorded as contingently redeemable common stock on the consolidated balance sheet as of December 31, 2010.

        The Stock Purchase Agreement prohibited the transfer of the Shares by Samsung for 18 months after the date of the Stock Purchase Agreement, subject to certain exceptions. After expiration of the transfer restriction period on July 18, 2011, the Stock Purchase Agreement provided that Samsung could transfer a limited number of shares on a daily basis, provide us with a right of first offer for proposed transfers above certain daily limits, and, if no sale occurs to us under the right of first offer, allowed Samsung to transfer the Shares. Under the Stock Purchase Agreement, we also agreed that after the transfer restriction period, Samsung would have certain rights to register the Shares for sale under the securities laws of the United States, subject to customary terms and conditions.

        On July 20, 2011, we received notice from Samsung exercising their option to put back to us approximately 4.8 million of the Shares for cash of $100.0 million. In August 2011, we paid $100.0 million to Samsung in exchange for the 4.8 million shares, which were retired. The difference between the amount recorded as contingently redeemable common stock and the cash paid was recorded as additional paid-in capital in our consolidated balance sheet.

        See Note 4, "Settlement Agreement with Samsung," of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.

Share Repurchase Program

        In October 2001, our Board of Directors (the "Board") approved a share repurchase program of our Common Stock, principally to reduce the dilutive effect of employee stock options. Under this program, the Board approved the authorization to repurchase up to 19.0 million shares of our outstanding Common Stock over an undefined period of time. On February 25, 2010, the Board approved a new share repurchase program authorizing the repurchase of up to an additional 12.5 million shares. Share repurchases under the program may be made through open market, established plan or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the program. The new share repurchase program replaces the program authorized in October 2001.

        On August 19, 2010, we entered into a share repurchase agreement (the "Share Repurchase Agreement") with J.P. Morgan Securities Inc., as agent for JPMorgan Chase Bank, National Association, London Branch ("JP Morgan") to repurchase approximately $90.0 million of our Common

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Stock, as part of our share repurchase program. Under the Share Repurchase Agreement, we pre-paid to JP Morgan the $90.0 million purchase price in the third quarter of 2010 for the Common Stock and JP Morgan delivered to us approximately 4.8 million shares of Common Stock at an average price of $18.88 at the completion of the Share Repurchase Agreement in December 2010.

        For the year ended December 31, 2011, we did not repurchase any shares of our Common Stock under our share repurchase program. For the year ended December 31, 2010, we repurchased approximately 9.5 million shares of our Common Stock with an aggregate price of approximately $195.1 million, including the price paid pursuant to the Share Repurchase Agreement. For the year ended December 31, 2009, we did not repurchase any shares of our Common Stock under our share repurchase program. As of December 31, 2011, we had repurchased a cumulative total of approximately 26.3 million shares of our Common Stock with an aggregate price of approximately $428.9 million since the commencement of the program in 2001. As of December 31, 2011, there remained an outstanding authorization to repurchase approximately 5.2 million shares of our outstanding Common Stock.

        We record stock repurchases as a reduction to stockholders' equity. We record a portion of the purchase price of the repurchased shares as an increase to accumulated deficit when the price of the shares repurchased exceeds the average original proceeds per share received from the issuance of Common Stock. During the year ended December 31, 2011, we did not repurchase any Common Stock. During the year ended December 31, 2010, the cumulative price of the shares repurchased exceeded the proceeds received from the issuance of the same number of shares. The excess of $163.6 million was recorded as an increase to accumulated deficit for the year ended December 31, 2010. During the year ended December 31, 2009, we did not repurchase any Common Stock.

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Item 6.    Selected Financial Data

        The following selected consolidated financial data for and as of the years ended December 31, 2011, 2010, 2009, 2008 and 2007 was derived from our consolidated financial statements. The following selected consolidated financial data should be read in conjunction with Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations," and Item 8, "Financial Statements and Supplementary Data," and other financial data included elsewhere in this report. Our historical results of operations are not necessarily indicative of results of operations to be expected for any future period.

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

        This report contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These statements relate to our expectations for future events and time periods. All statements other than statements of historical fact are statements that could be deemed to be forward-looking statements, including any statements regarding trends in future revenue or results of operations, gross margin or operating margin, expenses, earnings or losses from operations, synergies or other financial items; any statements of the plans, strategies and objectives of management for future operations; any statements concerning developments, performance or industry ranking; any statements regarding future economic conditions or performance; any statements regarding pending investigations, claims or disputes; any statements of expectation or belief; and any statements of assumptions underlying any of the foregoing. Generally, the words "anticipate," "believes," "plans," "expects," "future," "intends," "may," "should," "estimates," "predicts," "potential," "continue" and similar expressions identify forward-looking statements. Our forward-looking statements are based on current expectations, forecasts and assumptions and are subject to risks, uncertainties and changes in condition, significance, value and effect. As a result of the factors described herein, and in the documents incorporated herein by reference, including, in particular, those factors described under "Risk Factors," we undertake no obligation to publicly disclose any revisions to these forward-looking statements to reflect events or circumstances occurring subsequent to filing this report with the Securities and Exchange Commission.

Business Overview

        We are a premier intellectual property and technology licensing company focusing on the creation, design, development and licensing of patented innovations, technologies and architectures that are foundational to nearly all digital electronics products and systems. Our mission is to continuously enrich the end-user experience of electronic systems through groundbreaking innovations and technologies designed to improve the performance, power efficiency, time-to-market and cost-effectiveness of the products, components and systems offered by market-leading companies in semiconductors, computing, tablets, handheld devices, mobile applications, gaming and graphics, high definition televisions and displays, general lighting, cryptography and data security. Our inventors and engineering teams focus on creating innovations designed to address the most challenging demands of each target market and industry. We believe we have established an unparalleled licensing platform and business model that will continue to foster the development of new foundational technologies. By continuing to build upon this platform, our goal is to create additional licensing opportunities, and thereby perpetuate strong company operating performance and long-term stockholder value.

        While we have historically focused our efforts in the development of technologies for electronics memory and chip interfaces, we have been expanding our portfolio of inventions and solutions to address additional markets in lighting, displays, chip and system security, digital media, as well as new areas within the semiconductor industry, such as imaging and non-volatile memory. We intend to continue our growth into new technology fields, consistent with our mission to create great value through our innovations and to make those technologies available through our licensing business model. Key to our efforts, both in our current businesses and in any new area of diversification, will be hiring and retaining world-class inventors, scientists and engineers to lead the development of inventions and technology solutions for these fields of focus, and the management and business support personnel necessary to execute our plans and strategies.

        Prior to 2010, we operated in a single industry segment, the design, development and licensing of memory and logic interfaces, lighting and optoelectronics, and other technologies. In 2010, we reorganized, and as a result, currently have two business groups: SBG which focuses on the design, development and licensing of technology that is semiconductor based, and NBG which focuses on the design, development and licensing of technologies for lighting, displays, chip and system security, anti-counterfeiting, digital media and other markets. As of December 31, 2011, only SBG was

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considered a reportable segment as it met the quantitative thresholds for disclosure as a reportable segment. As such, segment information is not separately discussed below. For additional information concerning segment reporting, see Note 14, "Business Segments and Major Customers," of Notes to Consolidated Financial Statements of this Form 10-K.

        The key elements of our strategy are as follows:

        Innovate:     Develop and patent our innovative technology to provide fundamental competitive advantage when incorporated into semiconductors, and digital electronics products and systems.

        Drive Adoption:     Communicate the advantages of our patented innovations and technologies to the industry and encourage its adoption through demonstrations and incorporation in the products of select customers.

        Monetize:    License our patented inventions and technology solutions to customers for use in their semiconductor and system products.

        As of December 31, 2011, our semiconductor, lighting, display, security and other technologies are covered by 1,386 U.S. and foreign patents. Additionally, we have 1,059 patent applications pending. Some of the patents and pending patent applications are derived from a common parent patent application or are foreign counterpart patent applications. We have a program to file applications for and obtain patents in the United States and in selected foreign countries where we believe filing for such protection is appropriate and would further our overall business strategy and objectives. In some instances, obtaining appropriate levels of protection may involve prosecuting continuation and counterpart patent applications based on a common parent application. We believe that our patented innovations provide our customers means to achieve improved performance, lower risk, greater cost-effectiveness and other benefits in their products and services.

        Our patented inventions and technology solutions are offered to our customers through either a patent license or a solutions license. Our revenues are primarily derived from patent licenses, through which we provide our customers a license to use some specified portion of our broad portfolio of patented inventions. The patent license essentially provides our customers with a defined right to use our patented innovations in the customer's own digital electronics products, systems or services, as applicable. The patent licenses may also define the specific field of use where our customers may use or employ our inventions in their products. Patent license agreements are structured with fixed, variable or a hybrid of fixed and variable royalty payments over certain defined periods.

        We also offer our customers solutions licenses to support the implementation and adoption of our technology in their products or services. Our solutions license offerings include a range of solutions developed by Rambus, which include "leadership" solutions (which are Rambus-proprietary solutions widely licensed to our customers) and industry-standard solutions that we provide to our customers under license for incorporation into our customers' digital electronics products and systems. We offer a range of services as part of our solutions licenses which can include know-how and technology transfer, product design and development, system integration, supply chain consulting and other services. These solutions license agreements may have both a fixed price (non-recurring) component and ongoing royalties. Further, under solutions licenses, our customers typically receive licenses to our patents necessary to implement these solutions in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts with us.

        Royalties represent a substantial majority of our total revenue. We derive the majority of our royalty revenue by licensing our broad portfolio of patents for chip interfaces to our customers. These licenses may cover part or all of our patent portfolio across our breadth of technologies. Leading semiconductor and system companies such as AMD, Broadcom, Elpida, Freescale, Fujitsu, GE, Intel, Panasonic, Renesas, Samsung and Toshiba have licensed our patents for use in their own products.

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        We also derive additional revenue by licensing a range of technology solutions including our leadership and industry-standard solutions to customers for use in their digital electronics products and systems. Our customers include leading companies such as Elpida, GE, IBM, Panasonic, Samsung, Sony and Toshiba. Due to the often complex nature of implementing our technologies, we provide engineering services under certain of these licenses to help our customers successfully integrate our technology solutions into their semiconductor and system products. Licensees may also receive, in addition to their solutions license agreements, patent licenses as necessary to implement the technology in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts.

        The remainder of our revenue is contract services revenue which includes license fees and engineering services fees. The timing and amounts invoiced to customers can vary significantly depending on specific contract terms and can therefore have a significant impact on deferred revenue or account receivables in any given period.

        We intend to continue making significant expenditures associated with engineering, marketing, general and administration including litigation expenses, and expect that these costs and expenses will continue to be a significant percentage of revenue in future periods. Whether such expenses increase or decrease as a percentage of revenue will be substantially dependent upon the rate at which our revenue or expenses change.

Executive Summary

        During 2011, we renewed patent license agreements with Panasonic and Toshiba as well as signed a patent license agreement with Freescale and Broadcom. As a result of the patent license agreement with both Broadcom and Freescale, we settled all outstanding claims with them, including resolution of past use of our patented innovations. On June 3, 2011, we completed our largest acquisition to date, CRI, a security research and development and licensing company. We acquired all of the issued and outstanding common shares of CRI in exchange for cash of $168.8 million and Common Stock with a value of approximately $88.4 million at closing. This acquisition expands the breadth of Rambus' technologies available for licensing with complementary technologies from CRI that include patented innovations and solutions for content protection, network security and anti-counterfeiting. In connection with the acquisition of CRI, we are obligated to pay retention bonuses to certain CRI employees and contractors, subject to certain eligibility and acceleration provisions, including continued employment with us, in three equal amounts of approximately $16.7 million, with the first payment paid in cash and the remaining payments in cash or stock at our election, on June 3, 2012, 2013 and 2014, respectively. The total retention bonus commitment is $50.0 million and may be forfeited in part or whole by the covered employees and contractors upon voluntary departure from employment or discontinuation of services. Any amounts forfeited will be paid by us to a designated charity. See Note 18, "Acquisition," of Notes to Consolidated Financial Statements of this Form 10-K for further discussion. Additionally, we signed a patent license agreement in 2011 with a major smartphone and tablet manufacturer for the use of CRI's Differential Power Analysis ("DPA") countermeasures patents.

        Research and development continues to play a key role in our efforts to maintain product innovations. Our engineering expenses for the year ended December 31, 2011 increased $40.1 million as compared to 2010 primarily due to increased headcount related costs of $6.9 million from additional employees (including employees from our CRI acquisition) to support our development efforts, the accrual of the CRI retention bonuses of $15.7 million and increased amortization expenses related to intangible assets acquired of $13.6 million. Our lower revenue combined with the increase in engineering expenses has caused engineering expenses to increase as a percentage of revenue. Marketing, general and administrative expenses in aggregate increased $44.7 million for the year ended December 31, 2011 as compared to 2010 primarily due to litigation expenses being higher by $38.3 million. Our lower revenue combined with the increase in marketing, general and administrative

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expenses, has caused marketing, general and administrative expenses to increase as a percentage of revenue. Additionally, for the year ended December 31, 2011, we incurred costs of restatement and related legal activities of $16.2 million primarily due to the $10.9 million settlement in the matter captioned Stuart J. Steele, et al. v. Rambus Inc., et al., related to the previous stock option investigation, settling the claims against us and the individual defendants as well as the associated litigation expense.

Trends

        There are a number of trends that may or will have a material impact on us in the future, including but not limited to, the evolution of memory technology, adoption of LEDs in general lighting, and global economic conditions with the resulting impact on sales of consumer electronic systems.

        We have a high degree of revenue concentration, with our top five licensees representing approximately and 66%, 85% and 77% of our revenue for the years ended December 31, 2011, 2010 and 2009, respectively. As a result of our settlement with Samsung in 2010, Samsung is expected to account for a significant portion of our ongoing licensing revenue. For the year ended December 31, 2011, revenue from Elpida, NVIDIA and Samsung each accounted for 10% or more of our total revenue. For the year ended December 31, 2010, revenue from Elpida and Samsung each accounted for 10% or more of our total revenue. For the year ended December 31, 2009, revenue from AMD, Fujitsu, NEC, Panasonic, and Toshiba, each accounted for 10% or more of our total revenue. We expect to continue to experience significant revenue concentration for the foreseeable future.

        The particular licensees which account for revenue concentration have varied from period to period as a result of the addition of new contracts, expiration of existing contracts, renewals of existing contracts, industry consolidation and the volumes and prices at which the licensees have recently sold licensed semiconductors to system companies. These variations are expected to continue in the foreseeable future.

        The semiconductor industry is intensely competitive and highly cyclical. Our visibility with respect to future sales is very limited at this time. To the extent that macroeconomic fluctuations negatively affect our principal licensees, the demand for our technology may be significantly and adversely impacted and we may experience substantial period-to-period fluctuations in our operating results.

        The royalties we receive from our semiconductor business are partly a function of the adoption of our chip interfaces by system companies. Many system companies purchase semiconductors containing our chip interfaces from our licensees and do not have a direct contractual relationship with us. Our licensees generally do not provide us with details as to the identity or volume of licensed semiconductors purchased by particular system companies. As a result, we face difficulty in analyzing the extent to which our future revenue will be dependent upon particular system companies. System companies face intense competitive pressure in their markets, which are characterized by extreme volatility, frequent new product introductions and rapidly shifting consumer preferences.

        The display industry is also intensely competitive and highly cyclical. Since LED backlighting solutions are increasingly pervasive in LCD for computers, smartphones, tablets, game systems, high definition televisions and any user interface incorporating an active display, the continued move to higher resolution displays across these products requires more LEDs per system. The increased usage of LEDs is thereby creating a need for increased power efficiency since the LED backlight is the primary source of power consumption in many consumer electronics products, including smartphones. Our LDT group has numerous patents in edge lit LED lightguide technology. Our plans are to license our technology to key companies that use LED edge lit display products.

        The highly fragmented general lighting industry is undergoing a fundamental shift from incandescent technology to cold cathode fluorescent lights and LED driven technology by the need to reduce energy consumption and to comply with government mandates. LED lighting typically saves

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energy costs as compared to existing installed lighting. Our LDT group has numerous patents in LED edge lit lightguide technology which can be applied in the design of next generation LED lighting products. Our goal is to be a major player in the general lighting industry with our technology and have established a technology center in Brecksville, Ohio.

        Our revenue from companies headquartered outside of the United States accounted for approximately 67%, 93% and 83% of our total revenue for the years ended December 31, 2011, 2010 and 2009, respectively. We expect that revenue derived from international licensees will continue to represent a significant portion of our total revenue in the future. To date, all of the revenue from international licensees have been denominated in U.S. dollars. However, to the extent that such licensees' sales to their customers are not denominated in U.S. dollars, any royalties that we receive as a result of such sales could be subject to fluctuations in currency exchange rates. In addition, if the effective price of licensed semiconductors sold by our foreign licensees were to increase as a result of fluctuations in the exchange rate of the relevant currencies, demand for licensed semiconductors could fall, which in turn would reduce our royalties. We do not use financial instruments to hedge foreign exchange rate risk.

        For additional information concerning international revenue, see Note 14, "Business Segments and Major Customers," of Notes to Consolidated Financial Statements of this Form 10-K.

        Engineering costs in the aggregate and as a percentage of net sales increased in the year ended December 31, 2011 as compared to the prior year. In the near term, we expect engineering costs to be higher than in 2011 as we intend to continue to make investments in the infrastructure and technologies required to maintain our product innovations in semiconductor and lighting technologies and newly acquired businesses, such as CRI.

        Marketing, general and administrative expenses in the aggregate and as a percentage of net sales increased in the year ended December 31, 2011 as compared to the prior year. Historically, we have been involved in litigation stemming from the unlicensed use of our inventions. Our litigation expenses have been high and difficult to predict and future litigation expenses could be significant, volatile and difficult to predict. If we are successful in the litigation and/or related licensing, our revenue could be substantially higher in the future; if we are unsuccessful, our revenue may not grow or may decrease. Furthermore, our success in litigation matters pending before courts and regulatory bodies that relate to our intellectual property rights have impacted and will likely continue to impact our ability and the terms upon which we are able to negotiate new or renegotiate existing licenses for our technology. We will continue to pursue litigation against those companies that have infringed our patented technologies, which in turn will keep litigation expenses significant until such litigation is resolved.

        As we continue to pursue litigation and invest in research and development projects and if we experience lower revenue from our licensees in the future, our cash from operations will be negatively affected.

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Results of Operations

        The following table sets forth, for the periods indicated, the percentage of total revenue represented by certain items reflected in our consolidated statements of operations:

Royalty Revenue

Patent Licenses

        Our patent royalties decreased approximately $20.8 million to $267.6 million for the year ended December 31, 2011 from $288.4 million for the same period in 2010. The decrease was primarily due to the one-time recognition of royalty revenue from the settlement agreement signed with Samsung in 2010 which was partially offset by the revenue recognized from one-time and/or ongoing licensing

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agreements with NVIDIA, Broadcom, Freescale and a major smartphone and tablet manufacturer in 2011.

        In 2011, we renewed patent license agreements with Toshiba and Panasonic and signed new license agreements with Freescale, Broadcom and a major smartphone and tablet manufacturer. Some of these new agreements in 2011 had one-time catch up royalty payments, and in the aggregate, for 2011, these one-time payments for past dues amounted to $44.7 million dollars. In 2010, we renewed patent license agreements with AMD, Elpida and Renesas. In 2010, we also signed patent license agreement with NVIDIA and settlement agreement with Samsung. The one-time royalty payments from these new agreements in 2010 amounted to $136.4 million. Excluding the non-recurring portion from the patent royalties, the recurring patent royalties increased approximately $70.9 million to $222.9 million for the year ended December 31, 2011 from $152.0 million for the same period in 2010. The increase was primarily due to the complete allocation of Samsung's quarterly license payment to revenue since the second quarter of 2011 and revenue recognized from agreements signed since the third quarter of 2010.

        Our patent royalties increased approximately $209.1 million to $288.4 million for the year ended December 31, 2010 from $79.3 million for the same period in 2009. The increase was primarily due to the revenue recognized from the agreements signed with Samsung and Elpida during 2010.

        We are in negotiations with prospective licensees as well as existing licensees regarding renewals. We expect patent royalties will continue to vary from period to period based on our success in renewing existing license agreements and adding new licensees, as well as the level of variation in our licensees' reported shipment volumes, sales price and mix, offset in part by the proportion of licensee payments that are fixed or hybrid in nature.

Solutions Licenses

        Royalties from solutions licenses decreased approximately $0.4 million to $31.4 million for the year ended December 31, 2011 from $31.8 million for the same period in 2010. The decrease was primarily due to lower royalties reported from decreased shipments related to DDR2 technologies.

        Royalties from solutions licenses increased approximately $3.1 million to $31.8 million for the year ended December 31, 2010 from $28.7 million for the same period in 2009. The increase was primarily due to higher royalties reported from increased shipments related to DDR2 technologies and higher royalties from XDR™ DRAM associated with increased shipments of the Sony PlayStation®3 product, partially offset by lower royalties from RDRAM™ controllers in the first half of 2010 due to a one-time catch-up royalty payment for the Sony PlayStation®2 product in the second quarter of 2009.

        In the future, we expect solutions royalties will continue to vary from period to period based on our licensees' shipment volumes, sales prices, and product mix.

Contract Revenue

        Contract revenue increased approximately $10.2 million to $13.4 million for the year ended December 31, 2011 from $3.2 million for the year ended December 31, 2010. The increase was primarily due to new technology development contracts.

        Contract revenue decreased approximately $1.8 million to $3.2 million for the year ended December 31, 2010 from $5.0 million for the year ended December 31, 2009. The decrease was primarily due to fewer new technology development contracts and decrease in work performed on existing technology development contracts.

        We believe that contract revenue recognized will continue to fluctuate over time based on our ongoing contractual requirements, the amount of work performed, the timing of completing engineering

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deliverables, and by changes to work required, as well as new technology development contracts booked in the future.

Engineering costs:

        Engineering costs are allocated between cost of revenue and research and development expenses. Cost of revenue reflects the portion of the total engineering costs which are specifically devoted to individual licensee development and support services as well as amortization expense related to various acquired intellectual property for patent licensing. The balance of engineering costs, incurred for the development of applicable technologies, is charged to research and development. In a given period, the allocation of engineering costs between these two components is a function of the timing of the development and implementation schedules of individual licensee contracts.

        For the year ended December 31, 2011 as compared to the same period in 2010, total engineering costs increased 40.3% primarily due to increased headcount related costs of $6.9 million from additional employees (including employees from the CRI acquisition) to support our development efforts, increased amortization expense related to intangible assets acquired of $13.6 million as well as the accrual of the CRI retention bonuses of $15.7 million and higher prototyping costs of $3.1 million, offset by the $2.8 million decrease in funding for our 2011 corporate incentive plan ("CIP") which is lower than our 2010 CIP.

        For the year ended December 31, 2010 as compared to the same period in 2009, total engineering costs increased 34.4% primarily due to the increase in headcount from our LDT group and the funding for our 2010 CIP, which included the employee bonus related to the Samsung settlement, increase in patent research costs and additional amortization expense related to intangible assets acquired in a business combination in 2009.

        In the near term, we intend to continue to make investments in the infrastructure and technologies required to maintain our product innovation in semiconductor, lighting, security and other technologies.

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Marketing, general and administrative costs:

        Marketing, general and administrative expenses include expenses and costs associated with trade shows, public relations, advertising, litigation, general legal, insurance and other marketing and administrative efforts. Litigation expenses are a significant portion of our marketing, general and administrative expenses and can vary significantly from quarter to quarter. Consistent with our business model, our licensing and marketing activities aim to develop or strengthen relationships with potential and current licensees. In addition, we work with current licensees through marketing, sales and technical efforts to drive adoption of their products that use our innovations and solutions, by system companies. Due to the long business development cycles we face and the semi-fixed nature of marketing, general and administrative expenses in a given period, these expenses generally do not correlate to the level of revenue in that period or in recent or future periods.

        For the year ended December 31, 2011 as compared to 2010, total marketing, general and administrative costs increased 37.4% primarily due to the increased litigation expenses of $38.3 million related to ongoing major cases. Non-litigation related marketing, general and administrative costs increased for the year ended December 31, 2011 primarily due to the accrual of the CRI retention bonuses of $2.4 million and increased headcount related costs of $4.7 million from the increase in employees to support our business as well as higher consulting costs of $3.4 million and the acquisition costs related to CRI of $3.9 million, offset by the $5.0 million decrease in funding for our 2011 CIP, which is lower than our 2010 CIP, and lower stock-based compensation expense of $3.3 million.

        For the year ended December 31, 2010 as compared to 2009, total marketing, general and administrative costs decreased 6.8% primarily due to lower litigation expenses. Non-litigation related marketing, general and administrative costs increased for the year ended December 31, 2010 primarily due to funding for our 2010 CIP, which included the employee bonus related to the Samsung settlement, increased consulting fees, increased general legal expenses and increased headcount in corporate development commencing in 2009 as a result of our strategic initiatives to identify and acquire additional technology opportunities.

        In the future, marketing, general and administrative costs will vary from period to period based on the trade shows, advertising, legal, acquisition and other marketing and administrative activities undertaken, and the change in sales, marketing and administrative headcount in any given period. Litigation expenses are expected to vary from period to period due to the variability of litigation activities.

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Costs (recoveries) of restatement and related legal activities, net:

        Costs (recoveries) of restatement and related legal activities, net, consist primarily of settlement payments, investigation, audit, legal and other professional fees related to the 2006-2007 stock option investigation and the filing of the restated financial statements and related litigation.

        For the year ended December 31, 2011, costs of restatement and related legal activities were $16.2 million primarily due to a settlement payment and the litigation expense associated with a private shareholder lawsuit related to the 2006-2007 stock option investigation. In December 2011, we reached a settlement agreement that resolved the matter captioned Stuart J. Steele, et al. v. Rambus Inc., et al., where we have agreed to settle the claims against us and the individual defendants for approximately $10.9 million. Refer to Note 16, "Litigation and Asserted Claims," of Notes to Consolidated Financial Statements of this Form 10-K for additional details.

        For the year ended December 31, 2010, costs of restatement and related legal activities, net, were $4.2 million primarily due to litigation expense associated with the private shareholder lawsuit referred to above. In 2009, we recorded reimbursements of $12.3 million from the insurance carriers and received $4.5 million from former Rambus executives as part of their settlement agreements with us in connection with the derivative and class action lawsuits in 2009. Until all the litigation and related issues are resolved, we anticipate that there could be additional amounts relating to these matters in the future.

Gain from settlement:

        The settlement with Samsung is a multiple element arrangement for accounting purposes. For a multiple element arrangement, we are required to determine the fair value of the elements. We considered several factors in determining the accounting fair value of the elements of the settlement with Samsung which included a third party valuation using an income approach, the Black-Scholes-Merton option pricing model and a residual approach (collectively the "Fair Value"). The total gain from settlement is $133.0 million, of which $6.2 million was recognized during the year ended December 31, 2011. The total gain from settlement related to the settlement with Samsung of $133.0 million has been recognized as of the end of the first quarter of 2011. The gain from settlement represents the Fair Value of the cash consideration allocated to the resolution of the antitrust litigation settlement and the residual value of other elements.

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Interest and other income (expense), net:

        Interest income and other income (expense), net, consists primarily of interest income generated from investments in high quality fixed income securities offset by interest expense associated with our imputed facility lease obligations.

        Following the substantial completion of construction in the fourth quarter of 2010, we occupied our Sunnyvale and Brecksville facilities. In connection with the application of FASB authoritative guidance to our leases of the new facilities, we are deemed, in substance, to be the owner of the landlord's buildings, and therefore the estimated fair value of our portion of the buildings is required to be capitalized on our books as a non-cash transaction, offset by a corresponding imputed financing obligation on our balance sheet. The imputed financing obligations are amortized using the effective interest method with the imputed interest rate of approximately 10%. For the year ended December 31, 2011, we recognized $3.3 million of interest expense in connection with the imputed financing obligations in our statement of operations. For the year ended December 31, 2010, we recognized $0.4 million of interest expense in connection with the imputed financing obligations in our statement of operations. See Note 8, "Commitments and Contingencies," of Notes to Consolidated Financial Statements of this Form 10-K for additional details.

        Interest expense on convertible notes consists of non-cash interest expense related to the amortization of the debt discount on the 5% convertible senior notes due 2014 (the "2014 Notes") and the zero coupon convertible senior notes due 2010 (the "2010 Notes"), which were repaid during the first quarter of 2010, as well as the coupon interest related to the 2014 Notes. We expect interest expense to increase steadily as the 2014 Notes reach maturity. See Note 15, "Convertible Notes," of Notes to Consolidated Financial Statements of this Form 10-K for additional details.

Provision for (benefit from) income taxes:

        Our effective tax rate for the year ended December 31, 2011 is different from the U.S. statutory tax rate due to foreign withholding taxes, a full valuation allowance on our U.S. net deferred tax assets and foreign losses not benefitted, partially offset by foreign tax credits. Our effective tax rate for the year ended December 31, 2010 was different from the U.S. statutory tax due to a full valuation allowance on our U.S. net deferred tax assets, partially offset by foreign withholding taxes and state alternative minimum taxes. Our effective tax rate for the year ended December 31, 2009 was different

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from the U.S. statutory tax rate applied to our pretax loss primarily due to a full valuation allowance on our U.S. net deferred tax assets, foreign income taxes and state income taxes, partially offset by refundable research and development tax credits and carryback of net operating loss.

        For the year ended December 31, 2011, we paid withholding taxes of $16.6 million. We recorded a provision for income taxes of $17.3 million which is primarily comprised of withholding taxes, other foreign taxes and current state taxes.

        As of December 31, 2011, we continued to maintain a full valuation allowance against our U.S. net deferred tax assets. Management periodically evaluates the realizability of our net deferred tax assets based on all available evidence, both positive and negative. The realization of net deferred tax assets is dependent on our ability to generate sufficient future taxable income during periods prior to the expiration of tax statutes to fully utilize these assets. Based on all available evidence, we determined that it was not more likely than not that the deferred tax assets would be realized. Should we achieve sustained taxable income in the future, we would release the valuation allowance to recognize the deferred tax assets consisting of future tax deductions, net operating loss and credit carryforwards which provide a valuable benefit to us.

Liquidity and Capital Resources

Liquidity

        Our management continues to believe that total cash, cash equivalents and marketable securities will continue at adequate levels to finance our operations, projected capital expenditures and commitments for at least the next twelve months. Additionally, substantially all of our cash and cash equivalents are in the U.S. Our cash needs for 2011 were funded primarily from our operating activities, maturities of marketable securities, proceeds from the landlord for tenant improvements related to the lease in Sunnyvale and the issuance of common stock under our equity incentive plans.

        We currently anticipate that existing cash, cash equivalents and marketable securities balances and cash flows from operations will be adequate to meet our cash needs for at least the next 12 months. We do not anticipate any liquidity constraints as a result of either the current credit environment or investment fair value fluctuations. Additionally, we have the intent and ability to hold our debt investments that have unrealized losses in accumulated other comprehensive loss for a sufficient period of time to allow for recovery of the principal amounts invested. We continually monitor the credit risk in our portfolio and mitigate our credit risk exposures in accordance with our policies. As described elsewhere in this "Management's Discussion and Analysis of Financial Condition and Results of Operations" and this Annual Report on Form 10-K, we are involved in ongoing litigation related to our intellectual property and our past stock option investigation. Any adverse settlements or judgments in

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any of this litigation could have a material adverse impact on our results of operations, cash balances and cash flows in the period in which such events occur.

Operating Activities

        Cash provided by operating activities of $53.0 million for the year ended December 31, 2011 was primarily attributable to changes in operating assets and liabilities and the net loss adjusted for non-cash items, including stock-based compensation expense, non-cash interest expense, depreciation and amortization expense. Changes in operating assets and liabilities for the year ended December 31, 2011 primarily included increases in accounts payable, accrued litigation and decreases in prepaid expenses and other assets.

        Cash provided by operating activities of $235.2 million in the year ended December 31, 2010 was primarily attributable to the signing of Samsung and Elpida. In total, Samsung and Elpida provided approximately $300.2 million of net operating cash flow after applicable foreign tax withholdings. Additionally cash provided by operating activities included increases in accrued salaries due to the 2010 CIP and bonus related to the Samsung Settlement which was offset by decreases in accrued litigation and accounts payable.

        Cash used in operating activities of $40.6 million in the year ended December 31, 2009 was primarily attributable to the net loss adjusted for certain non-cash items including stock-based compensation expense, non-cash interest expense, depreciation and amortization expense. Changes in operating assets and liabilities which included decreases in accrued litigation expenses due to recognition of proceeds of $5.0 million from an insurance company related to the derivative and class action lawsuits offset by increases in accounts payable due to the timing of vendor payments.

Investing Activities

        Cash used in investing activities of $24.1 million for the year ended December 31, 2011 primarily consisted of cash paid for the acquisition of CRI of $167.4 million, net of cash acquired, and purchases of available-for-sale marketable securities of $174.0 million, partially offset by proceeds from the maturities of available-for-sale marketable securities of $337.9 million. In addition, we paid $19.4 million to acquire property and equipment, primarily computer equipment, machinery and software.

        Cash used in investing activities of approximately $181.5 million in the year ended December 31, 2010 primarily consisted of purchases of available-for-sale marketable securities of $428.8 million, partially offset by proceeds from the maturities of available-for-sale marketable securities of $296.6 million and proceeds from the sale of marketable securities of $1.8 million. We also purchased patents and businesses for an aggregate price of approximately $24.8 million. Additionally, we paid $26.7 million for the build-out of the facilities in Sunnyvale, California and Brecksville, Ohio as well as to acquire computer software, computer hardware and machinery and equipment.

        Cash provided by investing activities of approximately $24.5 million in the year ended December 31, 2009 primarily consisted of proceeds from the maturities of available-for-sale marketable securities of $240.9 million, partially offset by purchases of available-for-sale marketable securities of $183.2 million. In December 2009, we paid $26.0 million in a business combination to acquire technology and a portfolio of advanced lighting and optoelectronics patents from GLT. Additionally, we paid $2.7 million to acquire property, plant and equipment, primarily computer software, and $2.5 million for intangible assets. We also made a $2.0 million investment in a non-marketable equity security of a technology company.

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Financing Activities

        Cash used in financing activities was $81.9 million for the year ended December 31, 2011 as a result of the repurchase in August 2011 from Samsung of approximately 4.8 million shares of the Company's common stock for an aggregate amount of $100.0 million pursuant to a put option exercised by Samsung in accordance with the terms of a stock purchase agreement with Samsung dated January 19, 2010. This is partially offset by $8.8 million received from the landlord for the tenant improvements related to the lease in Sunnyvale and $12.3 million from issuance of common stock under equity incentive plans. We also made payments of $2.5 million under an installment payment plan to acquire intangible assets and computer software and $0.5 million related to the principal payments against the lease financing obligation.

        Cash used in financing activities was $127.5 million in the year ended December 31, 2010 was primarily due to the payment upon maturity of $137.0 million in face value of 2010 Notes and stock repurchased with an aggregate price of $195.1 million under our share repurchase program, which includes the shares purchased under Share Repurchase Agreement with J.P. Morgan, offset by proceeds received of $192.0 million from the issuance of common stock pursuant to the Stock Purchase Agreement with Samsung. Additionally, we received approximately $16.5 million from the issuance of common stock under equity incentive plans. We also made payments of $4.3 million under an installment payment plan to acquire intangible assets and computer software.

        Cash provided by financing activities was $188.9 million in the year ended December 31, 2009. We received proceeds of $168.2 million from the issuance of 2014 Notes. Additionally, we received approximately $20.7 million from the issuance of common stock under equity incentive plans.

Contractual Obligations

        On December 15, 2009, we entered into a definitive triple net space lease agreement with MT SPE, LLC (the "Landlord") whereby we leased approximately 125,000 square feet of office space located at 1050 Enterprise Way in Sunnyvale, California (the "Sunnyvale Lease"). The office space is used for our corporate headquarters, as well as engineering, marketing and administrative operations and activities. We moved to the premises in the fourth quarter of 2010 following substantial completion of leasehold improvements. The Sunnyvale Lease has a term of 120 months from the commencement date. The initial annual base rent is $3.7 million, subject to a full abatement of rent for the first six months of the Sunnyvale Lease term, but with the rent for the seventh month paid in December 2009 in order to gain access to the building. The annual base rent increases each year to certain fixed amounts over the course of the term as set forth in the Sunnyvale Lease and will be $4.8 million in the tenth year. In addition to the base rent, we also pay operating expenses, insurance expenses, real estate taxes and a management fee. We have two options to extend the Sunnyvale Lease for a period of 60 months each and a one-time option to terminate the Sunnyvale Lease after 84 months in exchange for an early termination fee.

        Since certain improvements constructed by us are considered structural in nature and given our responsibility for any cost overruns, for accounting purposes, we are treated in substance as the owner of the construction project during the construction period. At completion, we concluded that we retained sufficient continuing involvement to preclude de-recognition of the building under the FASB authoritative guidance applicable to the sale leasebacks of real estate. As such, we continue to account for the building as owned real estate and to record an imputed financing obligation for our obligation to the legal owner.

        Pursuant to the terms of the Sunnyvale Lease, the Landlord agreed to reimburse us approximately $9.1 million, of which $0.3 million was received in 2010 and $8.8 million was received in 2011. We recognized the reimbursement as an additional imputed financing obligation under the FASB

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authoritative guidance as such payment from the Landlord is deemed to be an imputed financing obligation.

        On November 4, 2011, to better plan for future expansion, we entered into an Amended Sunnyvale Lease (the "Amended Sunnyvale Lease") for approximately an additional 31,000 square feet of space. Similar to the original Sunnyvale Lease, we are required to construct the necessary tenant improvements for the premises to be capable of conducting business, which includes but is not limited to structural elements of the building. Additionally, the Landlord will provide a tenant improvement allowance estimated to be approximately $1.7 million. The Amended Sunnyvale Lease will have a commencement date of March 1, 2012 and will expire on June 30, 2020 (the same end date as the original Sunnyvale Lease). The base rent for the original Sunnyvale Lease will remain unchanged. The annual base rent for the Amended Sunnyvale Lease will initially be $1.1 million with rent abatement for the first five months of the lease term and increases annually over the course of the term as set forth in the Amended Sunnyvale Lease until it reaches $1.3 million.

        Since certain improvements to be constructed by us are considered structural in nature and we are responsible for any cost overruns, for accounting purposes, we are treated in substance as the owner of the construction project during the construction period. Accordingly, as of December 31, 2011, for the Amended Sunnyvale Lease, we capitalized an estimated $6.2 million in property, plant and equipment based on the estimated fair value of the portion of the unfinished space along with a corresponding financing obligation for the same amount.

        Monthly lease payments on the facility are allocated between the land element of the lease (which is accounted for as an operating lease) and the imputed financing obligation. The imputed financing obligation is amortized using the effective interest method and the interest rate was determined in accordance with the requirements of sale leaseback accounting. For the years ended December 31, 2011 and 2010, we recognized in our statement of operations $3.2 million and $0.4 million, respectively, of interest expense in connection with the imputed financing obligation. At December 31, 2011 and 2010, the imputed financing obligation balance in connection with the facility was $41.8 million and $27.3 million, respectively, which was primarily classified under long-term imputed financing obligation. At the end of the initial lease term, should we decide not to renew the lease, we would reverse the equal amounts of the net book value of the building and the corresponding imputed financing obligation.

        On March 8, 2010, we entered into a lease agreement with Fogg-Brecksville Development Co. (the "Ohio Landlord") for approximately 25,000 square feet of space consisting of approximately 7,000 square feet of office area and approximately 18,000 square feet of warehouse area, located in Brecksville, Ohio (the "Ohio Lease"). The office space is used for the LDT group's engineering activities while the manufacturing space is used for the manufacturer of prototypes for the LDT group. The Ohio Lease was amended on September 29, 2011 to expand the facility to approximately 51,000 total square feet (the "Amended Ohio Lease"), consisting of two extensions to be constructed by the Ohio Landlord ("Expansion A" and "Expansion B"). Expansion A will consist of approximately 11,000 square feet of space and Expansion B will consist of approximately 15,000 square feet of space. The Amended Ohio Lease has a term of 84 months from the First Extended Term Commencement Date as defined below. The First Extended Term Commencement Date is the first day of the month following substantial completion of Expansion B. Upon substantial completion of Expansion A, the annual base rent will be increased to $0.6 million. Upon substantial completion of Expansion B, the annual base rent will be increased to $0.8 million. The annual base rent increases each year on the anniversary date of the First Extended Term Commencement Date by 2% over the course of the term as set forth in the Amended Ohio Lease. We have an option to extend the Amended Ohio Lease for a period of 60 months.

        We undertook a series of structural improvements to ready the initial space for our use in 2010 and the Ohio Landlord began the construction of the building extensions during the fourth quarter of

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2011. Since certain improvements we constructed are considered structural in nature and we are responsible for any cost overruns, for accounting purposes, we are treated in substance as the owner of the construction project during the construction period. At completion of the initial construction period in 2010, we concluded that we retained sufficient continuing involvement to preclude de-recognition of the building under the FASB authoritative guidance applicable to the sale leasebacks of real estate. As such, we continue to account for the building as owned real estate and to record an imputed financing obligation for our obligation to the legal owner. Additionally, as of December 31, 2011, we capitalized $1.2 million in property, plant and equipment based on the estimated fair value of the portion of the unfinished building extensions along with a corresponding financing obligation for the same amount.

        The lease payments are recorded as interest expense using the effective interest method over the term of the lease. For the years ended December 31, 2011 and 2010, we recognized in our statement of operations $0.1 million and $29 thousand, respectively, of interest expense in connection with the imputed financing obligation on the Ohio facility. At December 31, 2011 and 2010, the imputed financing obligation balance in connection with the Ohio facility was $2.0 million and $0.8 million, respectively, which was classified under long-term imputed financing obligation. At the end of the intended use term, we would reverse the equal amounts of the net book value of the building and the corresponding imputed financing obligation.

        In November 2011, we entered into a lease agreement with Metropolitan Life Insurance (the "SF Landlord") for approximately 26,000 rentable square feet of office space in San Francisco, California (the "SF Lease") to be used for the CRI group's office space and which will be accounted as an operating lease. The SF Lease will have a commencement date of February 1, 2012 and a lease term of 75 months from the commencement date. The annual base rent for the SF Lease will be $0.9 million with a rent abatement for the first three months of the lease term and increases annually over the course of the term as set forth in the SF Lease until it reaches $1.0 million.

        In connection with the June 3, 2011 acquisition of CRI, we are obligated to pay retention bonuses to certain CRI employees and contractors, subject to certain eligibility and acceleration provisions including the condition of employment, in cash for the first retention milestone and cash or stock at the Company's election, for the following two payments. The three payments are to be equal amounts of approximately $16.7 million, on June 3, 2012, 2013 and 2014, respectively. The total retention bonus commitment is $50.0 million and may be forfeited in part or whole by the covered employees and contractors upon voluntary departure from employment or discontinuation of services. Any amounts forfeited will be accelerated and paid by us to a designated charity. See Note 18, "Acquisition," of Notes to Consolidated Financial Statements of this Form 10-K for additional information regarding the acquisition of CRI.

        On June 29, 2009, we entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by us of $150.0 million aggregate principal amount of 5% convertible senior notes due June 15, 2014. On July 10, 2009, an additional $22.5 million in aggregate principal amount of 2014 Notes were issued as a result of the underwriters exercising their overallotment option. The aggregate principal amount of the 2014 Notes outstanding as of December 31, 2011 was $172.5 million, offset by unamortized debt discount of $39.0 million in the accompanying consolidated balance sheets. The debt discount is currently being amortized over the remaining 30 months until maturity of the 2014 Notes on June 15, 2014. See Note 15, "Convertible Notes," of Notes to Consolidated Financial Statements of this Form 10-K for additional details.

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        As of December 31, 2011, our material contractual obligations are (in thousands):