STOCK BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of option activity

The option activity of the Plans for the year ended December 31, 2021, is as follows (shares in thousands):

				Weighted-Average
		Weighted-Average		Remaining	Aggregate
	Number of	Exercise Price		Contractual Term	Intrinsic Value
	Shares	per Share		(in years)	(in thousands)
Outstanding at January 1, 2021	19,553	$	1.53	7.75	$	306,408
Granted	86	$	4.47
Exercised	(5,732)	$	1.12
Forfeited/expired	(658)	$	1.46
Outstanding at December 31, 2021	13,249	$	1.73	7.23	$	42,775
Options vested at December 31, 2021	8,328	$	1.85	6.53	$	25,852
Options vested or expected to vest at December 31, 2021	12,704	$	1.74	7.18	$	40,852

Schedule of RSU activity

RSU activity under the 2020 Plan for the year ended December 31, 2021 is as follows (shares in thousands):

	Shares Subject	Weighted-Average
	to Vesting	Grant Date Fair Value
Balance of unvested shares as of January 1, 2021	683	$ 8.02
Granted	19,046	$ 7.12
Vested	(651)	$ 11.29
Cancelled/Forfeited	(2,683)	$ 3.12
Balance of unvested shares as of December 31, 2021	16,395	$ 7.54

RSU activity under the Plan

The activity for stock subject to vesting under the Plans for the year ended December 31, 2021 is as follows (shares in thousands):

	Shares Subject	Weighted-Average
	to Vesting	Grant Date Fair Value
Balance of unvested shares as of January 1, 2021	280	$ 4.08
Issuance of additional shares	476	$ 8.78
Vested	(492)	$ 6.64
Balance of unvested shares as of December 31, 2021	264	$ 7.79

Schedule of stock-based compensation expense

Total stock-based compensation expense related to all of the Company’s stock-based awards granted is reported in the consolidated statements of operations as follows (in thousands):

	Years Ended December 31,
	2021		2020
Research and development	$	11,446	$	3,276
General and administrative expense		10,939		3,464
Sales and marketing expense		4,593		894
Cost of sales		1,800		372
Total stock-based compensation expenses	$	28,778	$	8,006

Assumed Stock Options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions using Black-Scholes option-pricing model

Risk‑free interest rate		0.5% – 0.8	%
Expected volatility		57.2% – 59.4	%
Expected life (in years)		1.0 – 2.8
Expected dividend yield		—
Fair value of Common Stock	$	8.61

Market Based Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions using Black-Scholes option-pricing model

	October 2021
	Awards
Risk-free interest rate		1.3	%
Expected dividend yield		—	%
Remaining performance period (in years)		7.0
Expected volatility		55.0	%
Estimated grant date fair value (per share)	$	0.98 – 4.95
Target performance (number of shares)		9,070,269

Consultant

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions using Black-Scholes option-pricing model

	Year Ended
	December 31, 2020
Risk‑free interest rate		0.6% – 0.8	%
Expected volatility		54.3% – 54.8	%
Expected life (in years)		9.4 – 10.0
Expected dividend yield		—
Fair value of Common Stock	$	1.40 – 7.98

Employee

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions using Black-Scholes option-pricing model

	Year Ended
	December 31, 2020
Risk‑free interest rate		0.3% – 1.7	%
Expected volatility		52.7% – 54.2	%
Expected life (in years)		5.9 – 6.3
Expected dividend yield		—
Fair value of Common Stock	$	1.40 – 7.98