Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 17	$ 197
Marketable securities	2,700	3,998
Prepaid expenses and other assets	188	150
Total current assets	2,905	4,345
Property and equipment, net	1	3
Patent portfolios and patent rights, net		3,578
Investments at fair value	10,345	1,020
Deposit		26
Total assets	13,251	8,972
Current liabilities
Accounts payable and accrued expenses	132	56
Accrued salaries and benefits	732	695
Warrant liabilities	82	822
Payable to DatChat	207
Short-term deferred revenue		957
Short-term lease liabilities		48
Total current liabilities	1,153	2,578
Long-term deferred revenue		2,288
Total liabilities	1,153	4,866
Stockholders' equity
Common stock, $0.0001 par value, 100,000,000 shares authorized; 8,542,542 and 6,234,910 shares issued at December 31, 2018 and 2017, respectively; 8,542,530 and 6,234,898 shares outstanding at December 31, 2018 and 2017, respectively	1
Additional paid-in-capital	152,444	149,425
Treasury stock, at cost, 12 shares at December 31, 2018 and 2017	(264)	(264)
Accumulated deficit	(140,083)	(145,055)
Total stockholders' equity	12,098	4,106
Total liabilities and stockholders' equity	13,251	8,972
Series D Preferred Stock [Member]
Stockholders' equity
Preferred Stock
Series D-1 Convertible Preferred Stock [Member]
Stockholders' equity
Preferred Stock