Condensed Consolidated Balance Sheets (unaudited) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 6,422,358	$ 4,763,364
Short term investments	48,166,583	44,254,862
Accounts receivable	4,681,885	3,810,792
Income tax receivable	56,930	494,711
Deferred royalty buy-down	1,566,078	1,451,893
Prepaid expenses and other current assets	673,064	624,345
Total current assets	61,566,898	55,399,967
Long-term investments	6,717,196	3,771,380
Deferred royalty buy-down - long term, net	757,021	1,976,456
Deferred tax assets, net	2,992,001	3,290,122
Patent costs, net	227,868	258,355
Total assets	72,260,984	64,696,280
Current liabilities:
Accounts payable and accrued expenses	785,275	738,649
Deferred revenue	1,134,031	1,179,848
Accrued liabilities of discontinued operations	78,138	78,138
Total current liabilities	1,997,444	1,996,635
Long-term deferred revenue	5,555,743	6,417,702
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; 7,575,167 and 7,555,167 shares issued, 7,164,233 and 7,156,281 shares outstanding as of September 30, 2017 and December 31, 2016, respectively	7,575	7,555
Additional paid-in capital	33,303,898	32,945,240
Retained earnings	39,294,524	30,610,849
Treasury stock, 410,934 and 398,886 shares at cost as of September 30, 2017 and December 31, 2016, respectively	(7,898,200)	(7,281,701)
Total stockholders' equity	64,707,797	56,281,943
Total liabilities and stockholders' equity	$ 72,260,984	$ 64,696,280