Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Taxes

Schedule of effective tax rates differing from U.S. federal statutory rate

	December 31,
	2021				2020				2019
	(in thousands, except percentages)
U.S. federal taxes (benefit) at statutory rate	$	(98,931)	(21.00)	%	$	(48,226)	(21.00)	%	$	(25,794)	(21.00)	%
State tax expense		(29,206)	(6.20)	%		(10,672)	(4.65)	%		(6,607)	(5.38)	%
Research and development credits		(9,193)	(1.95)	%		(3,964)	(1.73)	%		(1,645)	(1.34)	%
Stock-based compensation		(46,128)	(9.80)	%		(23,791)	(10.36)	%		(7,544)	(6.14)	%
Foreign tax		167	0.04	%		55	0.02	%		1,612	1.31	%
Other nondeductible items		344	0.07	%		792	0.35	%		769	0.63	%
Nondeductible officers' compensation		24,387	5.18	%		8,984	3.91	%		609	0.50	%
Acquisition costs		8,901	1.89	%		—	—	%		—	—	%
Change in valuation allowance		150,277	31.90	%		76,920	33.50	%		40,599	33.05	%
Provision for income taxes	$	618	0.13	%	$	98	0.04	%	$	1,999	1.63	%

Schedule of tax effects of temporary differences that give rise to significant portions of the deferred tax assets

	December 31,
	2021		2020
	(in thousands)
Deferred tax assets:
Net operating loss carryforwards	$	315,552	$	177,899
Intangibles		4,443		—
Research and development tax credit carryforwards		38,725		24,332
Reserves and accruals		14,098		21,770
Lease Liabilities		16,843		7,123
Deferred revenue		6,363		6,386
Stock-based compensation		15,928		10,673
Total deferred tax assets before valuation allowance		411,952		248,183
Less: valuation allowance		(396,079)		(222,521)
		15,873		25,662
Deferred tax liabilities:
Convertible debt		—		(19,143)
Right-of-use lease assets		(15,873)		(6,519)
Net deferred tax assets	$	—	$	—

Schedule of reconciliation of the beginning and ending amount of gross unrecognized tax benefits

	December 31,
	2021		2020		2019
	(in thousands)
Balance at beginning of year	$	11,500	$	8,619	$	7,362
Additions based on tax positions related to the current year		6,017		2,889		1,426
Additions (reductions) for tax positions of prior years		(3)		(8)		(169)
Balance at end of year	$	17,514	$	11,500	$	8,619