Concentration of Credit Risk

3 Months Ended

Mar. 31, 2016

Concentration of Credit Risk

Concentrations of Credit Risk

4.     Concentration of Credit Risk

In December 2009, we entered into a license, development and commercialization agreement with Eli Lilly and Company (“Lilly”). In November 2009, we entered into a collaboration and license agreement with Novartis. The concentration of credit risk related to our collaborative partners is as follows:

	Percentage of Total
	Contract Revenues for the
	Three Months Ended
	March 31,
	2016		2015
Collaboration Partner A	—	%	89	%
Collaboration Partner B	100	%	11	%

Collaboration Partner A and Collaboration Partner B comprised in the aggregate 22% and 39% of the accounts receivable balance as of March 31, 2016 and December 31, 2015, respectively.

In November 2011, we began commercialization and distribution of JAKAFI to a number of customers. Our product revenues are concentrated in a number of these customers. The concentration of credit risk related to our product revenues is as follows:

	Percentage of Total Net
	Product Revenues for the
	Three Months Ended
	March 31,
	2016		2015
Customer A	27	%	28	%
Customer B	18	%	20	%
Customer C	12	%	13	%
Customer D	8	%	8	%

We are exposed to risks associated with extending credit to customers related to the sale of products. Customer A, Customer B, Customer C and Customer D comprised in the aggregate 48% and 40% of the accounts receivable balance as of March 31, 2016 and December 31, 2015, respectively.