v3.26.3
Stock-Based Awards
 9 Months Ended
Sep. 30, 2026
Share-Based Payment Arrangement [Abstract]  
Stock-Based Awards Stock-Based Awards
The Company has issued stock-based awards from various equity incentive and stock purchase plans, as more fully described in Note 9, "Stock-Based Awards" to the consolidated financial statements in the Company's 2025 Annual Report on Form 10-K.
Stock Option Activity
The following table summarizes stock option activity for the nine months ended September 30, 2026:
Number of Options
Weighted-Average
Exercise Price
Balance at December 31, 202521,326,333 $26.39 
Granted
2,980,999 17.70 
Exercised
(1,125,249)16.27 
Forfeited
(879,600)20.66 
Expired
(1,058,477)36.42 
Balance at September 30, 202621,244,006 $25.44 
Vested and expected to vest at September 30, 202621,244,006 $25.44 
Exercisable at September 30, 202614,444,354 $28.34 

The estimated fair value of stock options granted to employees was calculated using the Black-Scholes option-pricing model using the following assumptions:

Nine Months Ended September 30,
20262025
Expected term (in years)
5.50 - 6.08
5.50 - 6.08
Volatility
61.7% - 66.7%
64.8% - 68.7%
Risk-free interest rate
3.7% - 4.6%
3.6% - 4.5%
Dividend yield
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Restricted Stock Activity
The following table summarizes restricted stock unit ("RSU") activity for the nine months ended September 30, 2026:
Number of RSU sharesWeighted-Average Fair Value at Date of Grant per Share
Unvested at December 31, 20255,124,629 $21.74 
Granted3,904,424 17.49 
Vested and released(1,711,988)23.99 
Forfeited(781,347)19.34 
Unvested and expected to vest at September 30, 20266,535,718 $18.90 
Stock-Based Compensation Expense
The Company’s results of operations include expenses relating to stock-based compensation as follows (in thousands):
Three Months Ended September 30,Nine Months Ended September 30,
2026202520262025
Research and development
$12,976 $15,178 $40,024 $45,503 
General and administrative
9,883 9,957 28,837 30,179 
Total
$22,859 $25,135 $68,861 $75,682