Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 136,604	$ 127,540
Restricted cash	0	11,512
Short-term investments	0	19,443
Accounts receivable	153	26,750
Prepaid expenses and other current assets	2,938	3,245
Total current assets	139,695	188,490
Investments at fair value	104,754	0
Equity Method Investments	2,195	0
Loan receivable and accrued interest	0	18,616
Investment warrants	0	1,960
Patents, net of accumulated amortization	61,917	86,319
Other assets	207	618
Total assets	308,768	296,003
Current liabilities:
Accounts payable and accrued expenses	7,956	14,283
Royalties and contingent legal fees payable	1,601	13,908
Total current liabilities	9,557	28,191
Other liabilities	3,552	369
Total liabilities	13,109	28,560
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, par value $0.001 per share; 10,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, par value $0.001 per share; 100,000,000 shares authorized; 50,639,926 shares issued and outstanding as of December 31, 2017 and 50,476,042 shares issued and outstanding as of December 31, 2016	51	50
Treasury stock, at cost, 1,729,408 shares as of December 31, 2017 and 2016	(34,640)	(34,640)
Additional paid-in capital	648,996	642,453
Accumulated comprehensive loss	(88)	(76)
Accumulated deficit	(320,018)	(342,198)
Total Acacia Research Corporation stockholders’ equity	294,301	265,589
Noncontrolling interests in operating subsidiaries	1,358	1,854
Total stockholders’ equity	295,659	267,443
Total liabilities and stockholders' equity	$ 308,768	$ 296,003