Subsequent Event	3 Months Ended
Mar. 31, 2016
Subsequent event
Subsequent event	13. Subsequent event In April 2016, we entered into an amendment to the agreement with Novartis under which Novartis received exclusive research, development and commercialization rights outside of the United States to ruxolitinib (excluding topical formulations) in the GVHD field. We are eligible to receive future additional payments from Novartis if defined development and regulatory milestones relating to ruxolitinib for GVHD outside of the United States are achieved. In addition, we remain eligible to receive potential milestone payments and royalties on total sales of ruxolitinib (including GVHD) by Novartis outside of the United States. In April 2016, we closed on the agreement of sale with Augustine Land II, L.P. for the purchase of the previously leased land and office building. In May 2016, we entered into a share purchase agreement with ARIAD Pharmaceuticals, Inc. (“ARIAD”) and a wholly-owned subsidiary of ARIAD pursuant to which we will acquire all of the outstanding shares of a wholly-owned subsidiary of ARIAD that is the parent company of ARIAD’s European subsidiaries responsible for the development and commercialization of Iclusig® (ponatinib) in the European Union and 22 other countries (the “Territory”) for an upfront payment of $140.0 million. In addition, we agreed upon the terms of a license agreement to be entered into by ARIAD and us, pursuant to which we will be granted an exclusive license to develop and commercialize Iclusig in the Territory. ARIAD will be eligible to receive from us tiered royalties on net sales of Iclusig in the Territory and up to $135.0 million in potential future oncology development and regulatory approval milestone payments. The closing under the share purchase agreement and effectiveness of the license agreement is expected to occur on June 1, 2016, pending satisfaction of customary closing conditions. We believe that the transaction will be accounted for as a business combination. Please see Item 5(a) of Part II of this Quarterly Report on Form 10-Q for a more detailed description of the share purchase agreement and license agreement.

13. Subsequent event

In April 2016, we entered into an amendment to the agreement with Novartis under which Novartis received exclusive research, development and commercialization rights outside of the United States to ruxolitinib (excluding topical formulations) in the GVHD field. We are eligible to receive future additional payments from Novartis if defined development and regulatory milestones relating to ruxolitinib for GVHD outside of the United States are achieved. In addition, we remain eligible to receive potential milestone payments and royalties on total sales of ruxolitinib (including GVHD) by Novartis outside of the United States.

In April 2016, we closed on the agreement of sale with Augustine Land II, L.P. for the purchase of the previously leased land and office building.

In May 2016, we entered into a share purchase agreement with ARIAD Pharmaceuticals, Inc. (“ARIAD”) and a wholly-owned subsidiary of ARIAD pursuant to which we will acquire all of the outstanding shares of a wholly-owned subsidiary of ARIAD that is the parent company of ARIAD’s European subsidiaries responsible for the development and commercialization of Iclusig® (ponatinib) in the European Union and 22 other countries (the “Territory”) for an upfront payment of $140.0 million. In addition, we agreed upon the terms of a license agreement to be entered into by ARIAD and us, pursuant to which we will be granted an exclusive license to develop and commercialize Iclusig in the Territory. ARIAD will be eligible to receive from us tiered royalties on net sales of Iclusig in the Territory and up to $135.0 million in potential future oncology development and regulatory approval milestone payments. The closing under the share purchase agreement and effectiveness of the license agreement is expected to occur on June 1, 2016, pending satisfaction of customary closing conditions. We believe that the transaction will be accounted for as a business combination. Please see Item 5(a) of Part II of this Quarterly Report on Form 10-Q for a more detailed description of the share purchase agreement and license agreement.