Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 72,394	$ 53,942
Marketable debt securities	475,922	526,689
Marketable equity securities	39,706	42,431
Accounts receivable	19,861	28,997
Prepaid expenses	22,093	23,283
Total current assets	629,976	675,342
Property and equipment, net	66,685	59,183
Patents, licenses, and other intangible assets, net	18,244	18,500
Marketable debt securities - long term	0	3,826
Marketable equity securities - long term	54,210	54,383
Notes receivable - long term	0	0
Right of use (ROU) asset	33,697	34,419
Other assets	599	613
Total assets	803,411	846,266
Current liabilities
Accounts payable	15,341	10,088
Accrued expenses	15,140	18,728
Lease liabilities	4,471	4,708
Deferred revenue	30,104	30,320
Total current liabilities	65,056	63,844
Lease liabilities, net of current portion	54,772	54,926
Total liabilities	119,828	118,770
Commitments and contingencies
Stockholders’ equity
Preferred stock, $0.01 par value: 10,000,000 authorized shares; -0- issued and outstanding shares at March 31, 2023 and December 31, 2022	0	0
Common stock, $0.01 par value: 200,000,000 authorized shares at March 31, 2023 and December 31, 2022; 60,381,600 issued and outstanding at March 31, 2023 and 59,997,713 issued and outstanding at December 31, 2022	605	601
Additional paid-in capital	1,085,651	1,072,132
Accumulated other comprehensive loss	(3,625)	(6,952)
Accumulated deficit	(399,048)	(338,285)
Total stockholders’ equity	683,583	727,496
Total liabilities and stockholders’ equity	$ 803,411	$ 846,266