Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of Share-based Compensation, Stock Options, Activity

A summary of the Company’s stock option activity under the 2012 Plan, the 2018 Plan and the 2023 Plan, and related information is as follows:

		Options Outstanding
	Shares Available for Grant	Shares Subject to Options Outstanding	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
	(unaudited)
						(in thousands)
Balance as of January 1, 2024	12,003,394	4,012,903	$	31.76	6.6	$	39,115
2018 Plan annual increase(1)	3,689,000	—
Granted	(427,767)	427,767	23.23
Exercised	—	(577,352)	4.46
Canceled	112,592	(112,592)	45.93
Restricted stock units granted	(1,699,265)	—	—
Restricted stock units canceled	486,612	—	—
Market-based restricted stock units canceled	2,260,764	—	—
Performance-based restricted stock units granted	(870,268)	—	—
Performance-based restricted stock units adjusted for performance achievement	(48,234)	—	—
Performance-based restricted stock units canceled	36,852	—	—
Balance as of June 30, 2024	15,543,680	3,750,726	$	34.56	6.9	$	31,292
Vested and Exercisable as of June 30, 2024		2,087,390	$	34.05	5.3	$	26,747

(1)Effective as of January 1, 2024, an additional 3,689,000 shares of common stock became available for issuance under the 2018 Plan, as a result of the operation of an automatic annual increase provision therein.

Schedule of Restricted Stock Activity

A summary of the Company’s restricted stock unit activity excluding the performance-based and market-based restricted stock units under the 2012 Plan, the 2018 Plan and the 2023 Plan, and related information is as follows:

	Restricted Stock Units Outstanding	Weighted-Average Grant Date Fair Value
	(unaudited)
Balance as of January 1, 2024	4,346,785	$	42.63
Granted	1,699,265	20.49
Vested and released	(388,290)	50.31
Canceled	(486,612)	45.55
Balance as of June 30, 2024	5,171,148	$	34.51

A summary of the Company’s PSU activity under the 2018 Plan and related information is as follows:

	Performance-based Restricted Stock Units Outstanding	Weighted-Average Grant Date Fair Value
	(unaudited)
Balance as of January 1, 2024	412,490	$	91.25
Granted	870,268	18.09
Vested and released	(2,251)	32.86
Adjusted for performance achievement	48,234	32.84
Canceled	(36,852)	76.65
Balance as of June 30, 2024	1,291,889	$	40.30

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan

The following table presents the effect of employee and non-employee related stock-based compensation expense:

	Three Months Ended June 30,				Six Months Ended June 30,
	2024		2023		2024		2023
	(unaudited)
	(in thousands)
Cost of precision oncology testing	$	1,275	$	1,176	$	2,536	$	2,378
Cost of development services and other	495		477		990		951
Research and development expense	9,838		8,221		19,770		16,899
Sales and marketing expense	7,162		5,823		14,418		13,326
General and administrative expense	8,465		6,657		16,562		11,066
Total stock-based compensation expense	$	27,235	$	22,354	$	54,276	$	44,620

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The grant date fair value of stock options was estimated using a Black-Scholes option-pricing model with the following weighted-average assumptions:

	Three Months Ended June 30,		Six Months Ended June 30,
	2024	2023	2024	2023
	(unaudited)
Expected term (in years)	5.50 - 5.78	5.50 – 6.01	5.50 - 5.78	5.50 – 6.10
Expected volatility	67.8% - 69.4%	69.5% –70.5%	67.8% - 69.4%	69.5% –70.5%
Risk-free interest rate	4.4% - 4.5%	3.4% – 4.0%	4.3% - 4.5%	3.4% – 4.2%
Expected dividend yield	—%	—%	—%	—%

The grant date fair value of the stock purchase right granted under the ESPP was estimated using a Black-Scholes option-pricing model with the following assumptions:

	Three and Six Months Ended June 30,
	2024	2023
	(unaudited)
Expected term (in years)	0.50	0.50
Expected volatility	64.2%	76.6%
Risk-free interest rate	5.4%	5.2%
Expected dividend yield	—%	—%