v3.22.2.2
Stock-Based Compensation
 9 Months Ended
Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]  
Stock-Based Compensation Stock-Based Compensation
Stock-Based Compensation Expense

The following table summarizes total stock-based compensation expense (in thousands):

Three Months Ended September 30,Nine Months Ended September 30,
2021202220212022
Operations and support$11,162 $17,947 $36,810 $46,556 
Product development131,277 135,905 418,804 398,713 
Sales and marketing23,711 27,446 73,676 77,771 
General and administrative44,689 53,066 143,874 153,344 
Restructuring charges(50)— (38)8 
Stock-based compensation expense$210,789 $234,364 $673,126 $676,392 

Stock Option and Restricted Stock Unit Activity

The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option-pricing model using the range of assumptions in the following table:

Three Months Ended September 30, Nine Months Ended September 30,
2021202220212022
Expected term (years)
8.0
6.1
8.0
6.1
Risk-free interest rate
1.1%
0.3%
1.1% - 1.5%
0.3% - 2.2%
Expected volatility
44.2%
58.4%
44.2% - 44.9%
48.6% - 58.4%
Expected dividend yield— — — — 
A summary of stock option and restricted stock unit (“RSU”) activity under the Plans was as follows (in thousands, except per share amounts):

Outstanding
Stock Options
Outstanding
Restricted Stock Units
 Shares
Available for
Grant		Number of
Shares		Weighted-
Average
Exercise
Price		Number of
Shares		Weighted-
Average
Grant
Date Fair
Value
As of December 31, 202181,365 24,122 $19.69 36,789 $61.22 
Granted(11,054)698 161.70 10,356 142.50 
Increase in shares available for grant31,675 — — — — 
Shares withheld for taxes3,683 — — (3,683)79.70 
Exercised/Vested— (1,920)9.96 (6,050)80.78 
Canceled2,820 (382)95.88 (2,438)98.69 
As of September 30, 2022108,489 22,518 $23.63 34,974 $77.36 

Number of
Shares		Weighted-
Average
Exercise
Price		Weighted-
Average
Remaining
Contractual
Life (years)		Aggregate
Intrinsic
Value
Options outstanding as of September 30, 202222,518 $23.63 3.15$1,907,995 
Options exercisable as of September 30, 202220,219 $16.52 2.56$1,811,550 

Restricted Stock Awards

The Company has granted restricted stock awards (“RSAs”) to certain continuing employees, primarily in connection with acquisitions. Vesting of this stock is primarily dependent on a service-based vesting condition that generally becomes satisfied over a period of four years. The Company has the right to repurchase or cancel shares for which the vesting condition is not satisfied.

The following table summarizes the activity related to the Company’s RSAs (in thousands, except for per share amounts):

Number of
Shares		Weighted-Average
Grant-Date 
Fair Value
Per Share
Unvested RSAs as of December 31, 2021632 $62.32 
Vested(88)62.37 
Unvested RSAs as of September 30, 2022544 $62.32 

Employee Stock Purchase Plan (“ESPP”)

In December 2020, the Company’s board of directors adopted the ESPP. The maximum number of shares of Class A common stock authorized for sale under the ESPP is equal to the sum of (i) 4,000,000 shares of Class A common stock and (ii) an annual increase on the first day of each year beginning in 2022 and ending in 2030, equal to the lesser of (a) 1% of shares of Class A common stock (on an as converted basis) on the last day immediately preceding year and (b) such number of shares of common stock as determined by the board of directors; provided, however, that no more than 89,785,394 shares may be issued under the ESPP. The Company estimates the fair value of shares to be issued under the ESPP based on a combination of options valued using the Black-Scholes option-pricing model. The Company recorded stock-based compensation expense related to the ESPP of $24.7 million and $9.0 million for the three months ended September 30, 2021 and 2022, respectively, and $89.5 million and $22.9 million for the nine months ended September 30, 2021 and 2022, respectively.

During the nine months ended September 30, 2021, 0.5 million shares of common stock were purchased under the ESPP at a weighted-average price of $57.80 per share, resulting in net cash proceeds of $25.5 million. During the nine months ended September 30, 2022, 0.2 million shares of common stock were purchased under the ESPP at a weighted-average price of $103.23 per share, resulting in net cash proceeds of $20.3 million.