Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets
Cash	$ 57,738	$ 54,649
Marketable securities	70,206
Accounts receivable	408	2,966
Interest receivable	659
Prepaid expenses and other current assets	865	134
Total current assets	129,876	57,749
Property and equipment
Computers, software and equipment	5,275	4,270
Furniture and fixtures	102	97
Leasehold improvements	3,612	3,086
Less accumulated depreciation and amortization	(6,696)	(6,554)
Property and equipment, net	2,293	899
Other assets
Patents, licenses, and other intangible assets, net	9,617	9,116
Marketable securities - long term	69,632
Other assets	63	59
Total other assets	79,312	9,175
Total assets	211,481	67,823
Current liabilities
Accounts payable	5,107	1,691
Accrued expenses	3,817	2,251
Current portion of deferred revenue	47,652	2,254
Total current liabilities	56,576	6,196
Deferred rent, less current portion	659
Deferred revenue, less current portion	931	2,337
Total liabilities	$ 58,166	$ 8,533
Commitments and contingencies
Stockholders' equity
Common stock, $0.01 par value: 200,000,000 authorized shares at September 30, 2015 and December 31, 2014; 40,477,003 issued and outstanding at September 30, 2015 and 31,434,272 issued and outstanding at December 31, 2014	$ 405	$ 314
Additional paid-in capital	422,258	302,969
Accumulated other comprehensive loss	(6)
Accumulated deficit	(269,342)	(243,993)
Total stockholders' equity	153,315	59,290
Total liabilities and stockholders' equity	$ 211,481	$ 67,823