Consolidated Balance Sheets - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 5,137,875	$ 9,810,816
Short term investments	28,347,542	10,900,436
Accounts receivable	2,547,920	2,938,731
Income tax receivable	916,843	653,116
Deferred tax asset	16,911	16,907
Deferred royalty buy-down	1,017,981	569,641
Prepaid expenses and other current assets	383,810	259,163
Total current assets	38,368,882	25,148,810
Long-term investments	3,596,541	1,250,000
Deferred royalty buy-down - long term	2,851,423	3,271,120
Deferred tax assets - long term	606,061	1,061,864
Patent costs, net	275,206	295,030
Total assets	45,698,113	31,026,824
Current liabilities:
Accounts payable and accrued expenses	611,009	543,696
Deferred revenue - license fees	149,378	49,378
Accrued liabilities of discontinued operations	78,138	78,138
Total current liabilities	838,525	671,212
Deferred revenue - license fees	$ 49,379	$ 98,757
Commitments and contingencies (Note 10)
Stockholders' equity:
Series A Preferred stock, $.50 par value, 700,000 shares authorized; none outstanding	$ 0	$ 0
Common stock, $.001 par value; 10,000,000 shares authorized; 7,290,167 and 7,062,209 shares issued and 6,918,579 and 6,730,622 outstanding at December 31, 2015 and 2014, respectively	7,290	7,062
Additional paid-in capital	31,797,418	25,059,458
Retained earnings	19,238,610	9,620,978
Treasury stock, 371,588 and 331,587 shares at cost as of December 31, 2015 and 2014	(6,233,109)	(4,430,643)
Total stockholders' equity	44,810,209	30,256,855
Total liabilities and stockholders' equity	$ 45,698,113	$ 31,026,824