In November 2006, we entered into an exclusive collaboration agreement with Cephalon, aimed at identifying and developing clinical candidates that demonstrate activity towards the two designated target kinases of the collaboration: B-raf and a second undisclosed kinase. Cephalon paid us an upfront fee of $15.5 million as partial consideration for access to our profiling technology and the licenses we contributed to the collaboration. We may be entitled to receive up to $46.5 million in milestone payments upon the achievement of development, regulatory and sales milestones. In addition, we may receive tiered royalty payments calculated as a percentage of net sales of the collaboration compounds. The collaboration portion of the agreement ended in November 2009, at which point we had completed all our research obligations under the agreement.