Stock-based Compensation

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Stock-based Compensation

Stock-based CompensationStock-based compensation includes grants of equity incentive awards in the form of stock options and other stock-based awards as well as the issuance of common stock under a consulting agreement with a related party (see Note 14, Related Parties) and issuance of Earn-Out Shares to service providers in connection with the Business Combination.

There have been no significant changes to our equity incentive plans and types of stock-based incentive awards disclosed in our 2021 Form 10-K.

Stock-based compensation was recorded in the condensed consolidated statements of operations and comprehensive loss as shown in the following table:

	Three Months Ended March 31,
(in thousands)	2022		2021
Cost of assay services revenue	$	291	$	89
Cost of product revenue	7		1
Research and development	1,732		703
Selling, general and administrative	6,641		2,459
Total stock-based compensation	$	8,671	$	3,252

Stock-based compensation will fluctuate based on the grant-date fair value of awards, the number of awards, the requisite service period of the awards, modification of awards, employee forfeitures and the timing of the awards. Expense related to each stock option and restricted stock unit (“RSU”) award is recognized on a straight-line basis over the requisite service period of the entire award.

The following table summarizes our award activity for stock options and RSUs for the three months ended March 31, 2022:

	Stock Options(1)	RSUs(2)
Outstanding as of December 31, 2021	19,702,845	—
Granted	4,364,402	557,756
Exercised	(624,685)	—
Forfeited	(303,040)	(4,563)
Expired	—	n/a
Outstanding as of March 31, 2022	23,139,522	553,193

(1)    The stock options generally vest over four years, with 25% vesting upon the first-year anniversary of the grant date and the remaining options vesting ratably each month thereafter.

(2)    The RSUs vest subject to the satisfaction of service requirements. The grant date fair values of these awards are determined based on the closing price of our Common Stock on the date of grant.