Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Revenue:
Product sales	$ 844	$ 1,440
Royalties	2,166	1,644
Total Revenue	3,010	3,084
Cost of revenue:
Product sales	355	544
Royalties	92	90
Total Cost of revenue	447	634
Gross profit	2,563	2,450
Operating expenses:
Selling, general and administrative	1,761	1,436
Research and development	819	816
Total Operating expenses	2,580	2,252
Operating income (loss) from operations	(17)	198
Other, net	0	3
Income (loss) from operations before income taxes	(17)	201
Income tax expense	0	4
Net income (loss)	$ (17)	$ 197
Net income (loss) per share:
Basic (in dollars per share)	$ 0.00	$ 0.04
Diluted (in dollars per share)	$ 0.00	$ 0.04
Weighted average number of common shares outstanding:
Basic (in shares)	5,181	5,096
Diluted (in shares)	5,181	5,096

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