2. SPONSORED RESEARCH AND LICENSE AGREEMENTS

        We conduct research and development programs independently and in connection with our corporate collaborators. We currently do not have significant active collaborations.

• AstraZeneca

  Fostamatinib

        In February 2010, we entered into an exclusive worldwide license agreement with AZ for the development and commercialization of our oral SYK inhibitors for the treatment of human diseases other than those primarily involving respiratory or pulmonary dysfunction. The agreement included a license of rights to fostamatinib, our late-stage investigational product candidate for the treatment of RA and other indications. AZ was responsible for conducting and funding all future development, regulatory filings, manufacturing and global commercialization of products containing most of our oral SYK inhibitors. The agreement became effective on March 26, 2010, and we received an upfront payment from AZ of $100.0 million in April 2010. In September 2010, we earned $25.0 million from AZ for completing the transfer of the fostamatinib long-term open label extension study to AZ and for their initiation of Phase 3 clinical trials in the fostamatinib program by AZ. Under the agreement, our deliverables were: (i) granting a license of rights to fostamatinib, (ii) transfer of technology (know-how) related to fostamatinib, and (iii) conducting, at our expense, the fostamatinib open label extension study until it was transferred to AZ on September 25, 2010. We concluded that these deliverables should be accounted for as one single unit of accounting, and we recognized the $100.0 million upfront payment received in April 2010 from AZ ratably over the performance period from March 26, 2010, the effective date of the agreement, through September 25, 2010, the completion date of the last deliverable, which was the transfer of the fostamatinib long-term open label extension study to AZ. We elected a straight-line method for recognition of this upfront payment as the effort to advance and transfer the study was consistent over the short transition period.

        In June 2013, based on the totality of the results of the OSKIRA Phase 3 program in patients with RA, AZ informed us that it would not proceed with regulatory filings and, instead would return the rights to the compound to us. AZ was solely responsible for all costs and expenses incurred by both parties in connection with the transfer of responsibilities up to the effective termination of the agreement on December 4, 2013.

        In September 2013, we announced that we would not continue further development of fostamatinib for the treatment of RA or lymphoma due to insufficient efficacy findings from recent clinical trials and the competitive landscape in those indications.

• Other Agreements

        We have several active collaborations with additional partners. Under these collaborations, which we enter into in the ordinary course of business, we received or may be entitled to receive upfront cash payments, progress dependent contingent payments on events achieved by such partners and royalties on any net sales of products sold by such partners under the agreements. Total future contingent payments to us under all of these current collaborations could exceed $152.3 million if all potential product candidates achieved all of the payment triggering events under all of our current collaborations (based on a single product candidate under each agreement). Of this amount, up to $61.2 million relates to the achievement of development events, up to $53.6 million relates to the achievement of regulatory events and up to $37.5 million relates to the achievement of certain commercial or launch events. This estimated future contingent amount does not include any estimated royalties that could be due to us if the partners successfully commercialize the licensed products.

        Since we do not control the research, development or commercialization of the product candidates generated under these collaborations, we are not able to reasonably estimate when, if at all, any contingent payments would become payable to us. As such, the contingent payments we could receive thereunder involve a substantial degree of risk to achieve and may never be received. Accordingly, we do not expect, and investors should not assume, that we will receive all of the potential contingent payments provided for under these collaborations and it is possible that we may never receive any additional significant contingent payments or royalties under these collaborations.

        In June 2012, we entered into an exclusive worldwide license agreement with AZ for the development and commercialization of our program, R256, an inhaled JAK inhibitor shown to inhibit IL-13 and IL-4 signaling, which is being investigated as a treatment for moderate to severe chronic asthma. AZ is responsible for beginning the first-in-human clinical studies for R256, and for designing and conducting the clinical development of the compound. AZ also has exclusive rights to commercialize R256 around the world. AZ paid us an upfront payment of $1.0 million in July 2012. Under the agreement, we were obligated to provide the following deliverables: (i) granting a license of rights to our program, and (ii) delivery of a small batch of compound to AZ. We concluded that these deliverables should be accounted for as separate units of accounting. As our obligations with respect to the deliverables were achieved by June 30, 2012, we recognized revenue of $1.0 million in the second quarter of 2012. On December 31, 2013, we earned revenue associated with the time-based non-refundable payment of $5.8 million from AZ in consideration for AZ's decision to continue its development of R256 in asthma.

        In June 2011, we entered into an exclusive license agreement with BerGenBio for the development and commercialization of an oncology program, which is currently in Phase 1 development. BerGenBio is responsible for all activities it wishes to perform under the license we granted to it. In July 2012, we received a time-based payment of $500,000 from BerGenBio due to us on June 29, 2012, pursuant to the terms of the agreement. We recognized the payment as revenue in the second quarter of 2012.

        In August 2002, we entered into a collaboration agreement with Daiichi to pursue research related to a specific target from a novel class of drug targets called ligases that control cancer cell proliferation through protein degradation. In April 2013, we received a $1.4 million non-refundable payment from Daiichi related to Daiichi's filing of an IND for an oncology compound, which is currently in Phase 1 development. In January 2012, we received a $750,000 payment from Daiichi. To date, we have earned payments under this arrangement totaling $7.9 million and may earn additional payments in connection with the achievement by Daiichi of certain clinical events. The research phase of this three-year collaboration expired in August 2005. Under the terms of the collaboration agreement, we retain the rights to co-develop and co-promote certain products resulting from this collaboration in North America, while Daiichi retains co-development and promotion rights in the remainder of the world. Future events that may trigger payments to us under the Daiichi agreement are based solely on Daiichi's future efforts and achievements of specified events.