Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 1,646,646	$ 1,168,620
Marketable securities	942,800	521,713
Accounts receivable	150	144
Prepaid expenses and other current assets	31,347	26,143
Total current assets	2,620,943	1,716,620
Property and equipment, net	75,414	42,160
Intangible assets, net	153	180
Restricted cash	18,071	16,848
Operating lease assets	179,381	50,865
Other non-current assets	5,557	1,293
Total assets	2,899,519	1,827,966
Current liabilities:
Accounts payable	10,145	9,094
Accrued expenses	67,101	53,782
Deferred revenue, current	2,071	2,341
Accrued tax liabilities	4,463	10,473
Operating lease liabilities	15,875	11,362
Other current liabilities	268	7,207
Total current liabilities	99,923	94,259
Deferred revenue, non-current	11,775	11,776
Operating lease liabilities, net of current portion	175,329	50,067
Other non-current liabilities	8,697	7,630
Total liabilities	295,724	163,732
Commitments and contingencies, see Note 6
Shareholders’ equity:
Common shares, CHF 0.03 par value, 145,364,335 and 115,172,786 shares authorized at June 30, 2021 and December 31, 2020, respectively, 76,273,769 and 74,110,160 shares issued at June 30, 2021 and December 31, 2020, respectively, 76,078,453 and 73,914,844 shares outstanding at June 30, 2021 and December 31, 2020, respectively.	2,352	2,277
Treasury shares, at cost, 195,316 shares at June 30, 2021 and December 31, 2020.	(63)	(63)
Additional paid-in capital	2,529,649	2,235,679
Retained earnings (deficit)	72,486	(573,576)
Accumulated other comprehensive loss	(629)	(83)
Total shareholders' equity	2,603,795	1,664,234
Total liabilities and shareholders’ equity	$ 2,899,519	$ 1,827,966