Stockholders' Equity

9 Months Ended

Sep. 30, 2021

Note 9 – Stockholders' Equity

Equity Compensation Plans

We maintain four equity compensation plans that provide for the issuance of shares of our common stock to our officers and other employees, directors, and consultants: the 2010 Stock Plan (the “2010 Plan”), the 2013 Equity Incentive Plan (the “2013 Plan”), the 2019 Equity Incentive Plan (the “2019 Plan”), and the 2019 Employee Stock Purchase Plan (the “ESPP”), which have all been approved by stockholders. Following our IPO in 2019, we have only issued awards under the 2019 Plan and the ESPP, and no additional awards will be granted under the 2010 and 2013 Plans. These plans provide for the issuance of incentive stock options (“ISOs”), nonqualified stock options (“NSOs”), stock appreciation rights (“SARs”), restricted stock awards, restricted stock units (“RSUs”), performance-based awards, and other awards (that are based in whole or in part by reference to our common stock).

Stock Option and SAR Activity

A summary of stock option and SAR activity for the nine months ended September 30, 2021 is as follows (in millions, except share amounts which are reflected in thousands, per share amounts, and years):


	SARs Outstanding Number of SARs	Options Outstanding Number of Shares	Weighted-Average Exercise Price Per Share		Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value
As of December 31, 2020	229	28,734	$	12.87	4.97	$	1,104
Assumed in connection with an acquisition (1)	—	4,314	$	5.10
Exercised	(58)	(7,954)	$	11.82
Canceled and forfeited	(7)	(400)	$	18.99
As of September 30, 2021	164	24,694	$	11.76	4.38	$	821
Vested and expected to vest as of September 30, 2021	135	18,008	$	8.76	3.60	$	671
Exercisable as of September 30, 2021	135	18,008	$	8.76	3.60	$	671

(1) Refer to Note 16 – Business Combinations for additional information on our acquisition of Cornershop Cayman.

RSU Activity

The following table summarizes the activity related to our RSUs for the nine months ended September 30, 2021 (in thousands, except per share amounts):


	Number of Shares	Weighted-Average Grant-Date Fair Value per Share
Unvested and outstanding as of December 31, 2020	83,736	$	34.17
Granted	40,031	$	51.55
Vested	(29,500)	$	37.32
Canceled and forfeited	(19,106)	$	37.23
Unvested and outstanding as of September 30, 2021	75,161	$	41.45

Stock-Based Compensation Expense

Stock-based compensation expense is allocated based on the cost center to which the award holder belongs. The following table summarizes total stock-based compensation expense by function (in millions):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2021		2020		2021
Operations and support	$	16	$	42	$	52	$	107
Sales and marketing	11		18		35		60
Research and development	102		152		341		434
General and administrative	54		69		163		233
Total	$	183	$	281	$	591	$	834

As of September 30, 2021, there was $3.0 billion of unamortized compensation costs related to all unvested awards. The unamortized compensation costs are expected to be recognized over a weighted-average period of approximately 2.75 years.

The tax benefits recognized in the condensed consolidated statements of operations for stock-based compensation arrangements were not material during the three and nine months ended September 30, 2020 and 2021, respectively.