Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net income	$ 379,200	$ 109,100
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation	200
Contributed services		56,200
Changes in allowance for doubtful accounts	5,900	5,600
Gain on sale of patents	(269,800)
Unrealized gain from marketable securities	(14,200)
Changes in operating assets and liabilities:
Accounts receivable	(145,600)	(131,100)
Prepaid expenses and other current assets	(22,300)	(134,200)
Accounts payable	(8,500)	(11,500)
Accrued expenses	(13,100)	54,600
Accrued wages	3,900	8,100
Deferred revenue	78,000	(31,700)
Net cash used in operating activities	(6,300)	(74,900)
Cash flows from investing activities
Purchase of marketable securities	(242,600)
Proceeds from sale of patents	269,800
Purchase of property and equipment	(3,400)
Net cash provided by investing activities	23,800
Net change in cash	17,500	(74,900)
Cash, beginning of the period	4,375,300	1,541,900
Cash, end of the period	4,392,800	1,467,000
Supplemental disclosure of non-cash investing and financing information:
Non-cash activities: shares issued for settlement of accrued expenses		$ 39,600