Rover Group Inc - Ordinary Shares (ROVR) S-1/A 16 Nov 21 IPO registration (amended) Financial data

Cover Page

Cover Page	9 Months Ended
	Sep. 30, 2021
Cover [Abstract]
Document Type	S-1/A
Entity Registrant Name	ROVER GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Primary SIC Number	7200
Entity Tax Identification Number	85-3147201
Entity Address, Address Line One	720 Olive Way, 19th Floor
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98101
City Area Code	888
Local Phone Number	453-7889
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Central Index Key	0001826018
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($)	Sep. 30, 2021		Dec. 31, 2020		Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 290,327,000		$ 80,848,000		$ 67,654,000
Short-term investments			0		36,133,000
Accounts receivable, net	7,924,000		2,992,000		2,473,000
Prepaid expenses and other current assets	7,327,000		3,629,000		4,408,000
Total current assets	305,578,000		87,469,000		110,668,000
Property and equipment, net	21,952,000		24,923,000		30,991,000
Operating lease right-of-use assets	22,080,000		0
Intangible assets, net	5,260,000		7,967,000		13,151,000
Goodwill	33,159,000		33,159,000		33,159,000
Deferred tax asset, net	1,511,000		1,235,000		926,000
Other noncurrent assets	307,000		134,000		5,398,000
Total assets	389,847,000		154,887,000		194,293,000
Current liabilities
Accounts payable	3,480,000		1,301,000		5,769,000
Accrued compensation and related expenses	4,820,000		3,269,000		4,096,000
Accrued expenses and other current liabilities	2,829,000		2,747,000		4,663,000
Deferred revenue	6,003,000		751,000		2,488,000
Pet parent deposits	24,337,000		7,931,000		21,440,000
Pet service provider liabilities	9,743,000		6,140,000		11,460,000
Debt, current portion	0		4,128,000		0
Operating lease liabilities, current portion	2,726,000		0
Total current liabilities	53,938,000		26,267,000		49,916,000
Deferred rent, net of current portion	0		2,248,000		1,732,000
Debt, net of current portion	0		33,398,000		0
Operating lease liabilities, net of current portion	25,933,000		0
Earnout liabilities	266,390,000		0
Derivative warrant liabilities	34,294,000		0
Other noncurrent liabilities	795,000		4,659,000		3,977,000
Total liabilities	381,350,000		66,572,000		55,625,000
Commitments and contingencies (Note 10)
Redeemable convertible preferred stock, $0.00001 par value, 87,611 shares authorized as of December 31, 2019 and 2020; 90,805 and 90,814 shares issued and outstanding as of December 31, 2019 and 2020, respectively; aggregate liquidation preference of $294,740 and $294,802 as of December 31, 2019 and 2020, respectively	0	[1]	290,427,000	[2]	290,365,000	[2]
Stockholders’ equity (deficit):
Preferred stock, $0.0001 par value, 10,000 and no shares authorized as of September 30, 2021 and December 31, 2020, respectively; no shares issued and outstanding as of September 30, 2021 and December 31, 2020 respectively	0		0
Common stock, $0.0001 par value, 144,250 shares authorized as of December 31, 2019 and 2020; 29,614 and 30,398 shares issued and outstanding as of December 31, 2019 and 2020, respectively	16,000		3,000		3,000
Additional paid-in capital	362,471,000		53,909,000		46,923,000
Accumulated other comprehensive income	220,000		253,000		169,000
Accumulated deficit	(354,210,000)		(256,277,000)		(198,792,000)
Total stockholders’ equity (deficit)	8,497,000		(202,112,000)		(151,697,000)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	$ 389,847,000		$ 154,887,000		$ 194,293,000
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021		Dec. 31, 2020		Dec. 31, 2019
Statement of Financial Position [Abstract]
Convertible preferred stock, par value (in dollars per share)	$ 0.00001		$ 0.00001		$ 0.00001
Convertible preferred stock, shares authorized (in shares)			87,611,000		87,611,000
Convertible preferred stock, shares issued (in shares)			90,814,000		90,805,000
Convertible preferred stock, shares outstanding (in shares)	0	[1]	90,814,000	[1]	90,805,000	[2]
Convertible preferred stock, liquidation preference			$ 294,802		$ 294,740
Preferred stock, par value (in dollars per share)	$ 0.0001		$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000		0
Preferred stock, shares issued (in shares)	0		0
Preferred stock, shares outstanding (in shares)	0		0
Common stock, par value (in dollars per share)	$ 0.0001		$ 0.0001		$ 0.0001
Common stock, shares authorized (in shares)	990,000,000		144,250,000		144,250,000
Common stock, shares issued (in shares)	157,593,000		30,398,000		29,614,000
Common stock, shares outstanding (in shares)	157,593,000		30,398,000		29,614,000
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Revenue	$ 35,153	$ 13,260	$ 71,831	$ 35,632	$ 48,800	$ 95,052	$ 71,411
Costs and expenses:
Cost of revenue (exclusive of depreciation and amortization shown separately below)	8,036	4,322	18,494	15,949	19,823	23,522	16,173
Operations and support	4,199	2,460	9,916	9,997	12,371	19,882	17,430
Marketing	6,403	2,403	13,532	13,899	16,332	49,921	58,845
Product development	5,033	4,355	14,586	18,093	22,567	22,066	16,886
General and administrative	8,899	4,958	21,266	15,761	21,813	24,947	22,390
Depreciation and amortization	1,873	2,105	5,572	6,967	8,899	8,390	7,125
Total costs and expenses	34,443	20,603	83,366	80,666	101,805	148,728	138,849
Income (loss) from operations	710	(7,343)	(11,535)	(45,034)	(53,005)	(53,676)	(67,438)
Other income (expense), net:
Interest income	19	22	28	483	488	2,807	2,654
Interest expense	(1,534)	(1,185)	(2,933)	(2,443)	(3,154)	(204)	(141)
Loss from impairment of DogHero investment	0	(2,000)	0	(2,000)	(2,080)	0	0
Change in fair value of earnout liabilities	(71,318)	0	(71,318)	0
Change in fair value of derivative warrant liabilities	(12,261)	0	(12,261)	0
Other income (expense), net	(116)	77	(194)	(111)	172	(1,109)	(21)
Total other income (expense), net	(85,210)	(3,086)	(86,678)	(4,071)	(4,574)	1,494	2,492
Loss before income taxes	(84,500)	(10,429)	(98,213)	(49,105)	(57,579)	(52,182)	(64,946)
Benefit from (provision for) income taxes	(36)	70	280	122	94	468	269
Net loss	$ (84,536)	$ (10,359)	$ (97,933)	$ (48,983)	(57,485)	(51,714)	(64,677)
Deemed dividend to preferred stockholders					0	0	(491)
Net loss attributable to common stockholders					$ (57,485)	$ (51,714)	$ (65,168)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.73)	$ (0.35)	$ (1.64)	$ (1.64)	$ (1.92)	$ (1.77)	$ (2.40)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.73)	$ (0.35)	$ (1.64)	$ (1.64)	$ (1.92)	$ (1.77)	$ (2.40)
Weighted-average shares used in computing net loss per share, basic (in shares)	116,597,000	30,008,000	59,825,000	29,834,000	29,896,000	29,138,000	27,150,000
Weighted-average shares used in computing net loss per share, diluted (in shares)	116,597,000	30,008,000	59,825,000	29,834,000	29,896,000	29,138,000	27,150,000

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (84,536)	$ (10,359)	$ (97,933)	$ (48,983)	$ (57,485)	$ (51,714)	$ (64,677)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(62)	113	(33)	(27)	148	117	(12)
Unrealized gain (loss) on available-for-sale securities	0	(104)	0	(64)	(64)	71	23
Other comprehensive income (loss)	(62)	9	(33)	(91)	84	188	11
Comprehensive loss	$ (84,598)	$ (10,350)	$ (97,966)	$ (49,074)	$ (57,401)	$ (51,526)	$ (64,666)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands		Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock		Additional Paid-in Capital		Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Accumulated DeficitCumulative Effect, Period of Adoption, Adjustment
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2017	[1]	71,692,000
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2017	[1]	$ 153,074
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback (in shares)	[1]	17,233,000
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback	[1]	$ 123,655
Issuance of Series G redeemable convertible preferred stock and common stock for acquisition of Barking Dog Ventures, Ltd. (in shares)	[1]	1,380,000
Issuance of Series G redeemable convertible preferred stock and common stock for acquisition of Barking Dog Ventures, Ltd.	[1]	$ 10,007
Redeemable Convertible Preferred Stock, ending balance (in shares) at Dec. 31, 2018	[1]	90,305,000
Redeemable Convertible Preferred Stock, ending balance at Dec. 31, 2018	[1]	$ 286,736
Beginning balance (in shares) at Dec. 31, 2017	[1]			25,521,000
Beginning balance at Dec. 31, 2017		$ (53,599)		$ 3	[1]	$ 29,441	[1]	$ (30)	$ (83,013)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible Enumeration]		Accounting Standards Update 2014-09
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization (in shares)	[1]			1,337,000
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization		$ 4,304				4,304	[1]
Issuance of common stock from exercises of stock options (in shares)	[1]			1,920,000
Issuance of common stock from exercises of stock options		726				726	[1]
Stock-based compensation		6,682				6,682	[1]
Issuance of common stock warrants		239				239	[1]
Foreign currency translation adjustments		(12)						(12)
Unrealized gain (loss) on available-for-sale securities		23						23
Net loss		(64,677)							(64,677)
Ending balance (in shares) at Dec. 31, 2018	[1]			28,778,000
Ending balance at Dec. 31, 2018		$ (106,314)	$ 612	$ 3	[1]	41,392	[1]	(19)	(147,690)	$ 612
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback (in shares)	[1]	500,000
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback	[1]	$ 3,629
Redeemable Convertible Preferred Stock, ending balance (in shares) at Dec. 31, 2019	[1]	90,805,000
Redeemable Convertible Preferred Stock, ending balance at Dec. 31, 2019	[1]	$ 290,365
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization (in shares)	[1]			1,000
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization		$ 4				4	[1]
Issuance of common stock from exercises of stock options (in shares)		966,000		835,000	[1]
Issuance of common stock from exercises of stock options		$ 773				773	[1]
Stock-based compensation		4,067				4,067	[1]
Issuance of common stock warrants		687				687	[1]
Foreign currency translation adjustments		117						117
Unrealized gain (loss) on available-for-sale securities		71						71
Net loss		(51,714)							(51,714)
Ending balance (in shares) at Dec. 31, 2019	[1]			29,614,000
Ending balance at Dec. 31, 2019		$ (151,697)		$ 3	[1]	46,923	[1]	169	(198,792)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback (in shares)		9,000
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback		$ 62
Redeemable Convertible Preferred Stock, ending balance (in shares) at Mar. 31, 2020		90,814,000
Redeemable Convertible Preferred Stock, ending balance at Mar. 31, 2020		$ 290,427
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)				128,000
Issuance of common stock from exercises of stock options		134				134
Stock-based compensation		1,585				1,585
Issuance of common stock warrants		657				657
Foreign currency translation adjustments		141						141
Unrealized gain (loss) on available-for-sale securities		(115)						(115)
Net loss		(20,545)							(20,545)
Ending balance (in shares) at Mar. 31, 2020				29,742,000
Ending balance at Mar. 31, 2020		$ (169,840)		$ 3		49,299		195	(219,337)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2019	[1]	90,805,000
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2019	[1]	$ 290,365
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2020		90,814,000
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2020		$ 290,427
Beginning balance (in shares) at Dec. 31, 2019	[1]			29,614,000
Beginning balance at Dec. 31, 2019		(151,697)		$ 3	[1]	46,923	[1]	169	(198,792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments		(27)
Unrealized gain (loss) on available-for-sale securities		(64)
Net loss		(48,983)
Ending balance (in shares) at Sep. 30, 2020				30,015,000
Ending balance at Sep. 30, 2020		$ (195,405)		$ 3		52,289		78	(247,775)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2019	[1]	90,805,000
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2019	[1]	$ 290,365
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback (in shares)	[1]	9,000
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. holdback	[1]	$ 62
Redeemable Convertible Preferred Stock, ending balance (in shares) at Dec. 31, 2020	[2]	90,814,000
Redeemable Convertible Preferred Stock, ending balance at Dec. 31, 2020	[1]	$ 290,427
Beginning balance (in shares) at Dec. 31, 2019	[1]			29,614,000
Beginning balance at Dec. 31, 2019		$ (151,697)		$ 3	[1]	46,923	[1]	169	(198,792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)		907,000		784,000	[1]
Issuance of common stock from exercises of stock options		$ 788				788	[1]
Stock-based compensation		5,541				5,541	[1]
Issuance of common stock warrants		657				657	[1]
Foreign currency translation adjustments		148						148
Unrealized gain (loss) on available-for-sale securities		(64)						(64)
Net loss		(57,485)							(57,485)
Ending balance (in shares) at Dec. 31, 2020	[1]			30,398,000
Ending balance at Dec. 31, 2020		$ (202,112)		$ 3	[1]	53,909	[1]	253	(256,277)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Mar. 31, 2020		90,814,000
Redeemable Convertible Preferred Stock, beginning balance at Mar. 31, 2020		$ 290,427
Redeemable Convertible Preferred Stock, ending balance (in shares) at Jun. 30, 2020		90,814,000
Redeemable Convertible Preferred Stock, ending balance at Jun. 30, 2020		$ 290,427
Beginning balance (in shares) at Mar. 31, 2020				29,742,000
Beginning balance at Mar. 31, 2020		(169,840)		$ 3		49,299		195	(219,337)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)				86,000
Issuance of common stock from exercises of stock options		117				117
Stock-based compensation		894				894
Foreign currency translation adjustments		(281)						(281)
Unrealized gain (loss) on available-for-sale securities		155						155
Net loss		(18,079)							(18,079)
Ending balance (in shares) at Jun. 30, 2020				29,828,000
Ending balance at Jun. 30, 2020		$ (187,034)		$ 3		50,310		69	(237,416)
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2020		90,814,000
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2020		$ 290,427
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)				187,000
Issuance of common stock from exercises of stock options		190				190
Stock-based compensation		1,789				1,789
Foreign currency translation adjustments		113						113
Unrealized gain (loss) on available-for-sale securities		(104)						(104)
Net loss		(10,359)							(10,359)
Ending balance (in shares) at Sep. 30, 2020				30,015,000
Ending balance at Sep. 30, 2020		$ (195,405)		$ 3		52,289		78	(247,775)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2020	[2]	90,814,000
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2020	[1]	$ 290,427
Redeemable Convertible Preferred Stock, ending balance (in shares) at Mar. 31, 2021	[2]	90,814,000
Redeemable Convertible Preferred Stock, ending balance at Mar. 31, 2021	[2]	$ 290,427
Beginning balance (in shares) at Dec. 31, 2020	[1]			30,398,000
Beginning balance at Dec. 31, 2020		(202,112)		$ 3	[1]	53,909	[1]	253	(256,277)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)	[2]			470,000
Issuance of common stock from exercises of stock options		666				666	[2]
Stock-based compensation		1,001				1,001	[2]
Foreign currency translation adjustments		21						21
Net loss		(10,591)							(10,591)
Ending balance (in shares) at Mar. 31, 2021	[2]			30,868,000
Ending balance at Mar. 31, 2021		$ (211,015)		$ 3	[2]	55,576	[2]	274	(266,868)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2020	[2]	90,814,000
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2020	[1]	$ 290,427
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2021	[2]	0
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2021	[2]	$ 0
Beginning balance (in shares) at Dec. 31, 2020	[1]			30,398,000
Beginning balance at Dec. 31, 2020		$ (202,112)		$ 3	[1]	53,909	[1]	253	(256,277)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)		2,881,000
Foreign currency translation adjustments		$ (33)
Unrealized gain (loss) on available-for-sale securities		0
Net loss		(97,933)
Ending balance (in shares) at Sep. 30, 2021	[2]			157,593,000
Ending balance at Sep. 30, 2021		$ 8,497		$ 16	[2]	362,471	[2]	220	(354,210)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Mar. 31, 2021	[2]	90,814,000
Redeemable Convertible Preferred Stock, beginning balance at Mar. 31, 2021	[2]	$ 290,427
Redeemable Convertible Preferred Stock, ending balance (in shares) at Jun. 30, 2021	[2]	90,814,000
Redeemable Convertible Preferred Stock, ending balance at Jun. 30, 2021	[2]	$ 290,427
Beginning balance (in shares) at Mar. 31, 2021	[2]			30,868,000
Beginning balance at Mar. 31, 2021		(211,015)		$ 3	[2]	55,576	[2]	274	(266,868)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercises of stock options (in shares)	[2]			392,000
Issuance of common stock from exercises of stock options		816				816	[2]
Issuance of common stock from net exercises of warrants (in shares)	[2]			331,000
Stock-based compensation		1,147				1,147	[2]
Foreign currency translation adjustments		8						8
Net loss		(2,806)							(2,806)
Ending balance (in shares) at Jun. 30, 2021	[2]			31,591,000
Ending balance at Jun. 30, 2021		$ (211,850)		$ 3	[2]	57,539	[2]	282	(269,674)
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization (in shares)	[2]	90,814,000
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization	[2]	$ 290,427
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2021	[2]	0
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2021	[2]	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization (in shares)	[2]			90,814,000
Conversion of redeemable convertible preferred stock to common stock in connection with reverse recapitalization		290,427		$ 9	[2]	290,418	[2]
Reverse recapitalization transaction, net of costs (in shares)	[2]			32,721,000
Reverse recapitalization transaction, net of costs and acquired liabilities		213,459		$ 4	[2]	213,455	[2]
Earnout liability recognized upon the closing of the reverse recapitalization		(228,082)				(228,082)	[2]
Reclassification of earnout liability upon settlement		33,010				33,010	[2]
Issuance of common stock from exercises of stock options (in shares)	[2]			2,019,000
Issuance of common stock from exercises of stock options		1,856				1,856	[2]
Issuance of common stock from net exercises of warrants (in shares)	[2]			448,000
Taxes paid on net share settlement		(6,719)				(6,719)	[2]
Stock-based compensation		994				994	[2]
Foreign currency translation adjustments		(62)						(62)
Unrealized gain (loss) on available-for-sale securities		0
Net loss		(84,536)							(84,536)
Ending balance (in shares) at Sep. 30, 2021	[2]			157,593,000
Ending balance at Sep. 30, 2021		$ 8,497		$ 16	[2]	$ 362,471	[2]	$ 220	$ (354,210)
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parentheticals)	Jul. 30, 2021	Dec. 31, 2020
Statement of Stockholders' Equity [Abstract]
Recapitalization exchange ratio	1.0379	1.0379

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
OPERATING ACTIVITIES
Net loss	$ (97,933)	$ (48,983)	$ (57,485)	$ (51,714)	$ (64,677)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	3,142	4,268	5,541	4,067	6,682
Depreciation and amortization	10,815	15,099	18,713	13,596	9,656
Non-cash operating lease costs	1,490	0
Change in fair value of earnout liabilities	71,318	0
Change in fair value of derivative warrant liabilities	12,261	0
Net amortization (accretion) of investment premiums (discounts)	0	11	11	(639)	(700)
Issuance of common stock warrants			0	453	189
Amortization of debt issuance costs	695	721	841	186	59
Deferred income taxes	(309)	(314)	(303)	(588)	(278)
Loss on disposal of property and equipment	17	81	191	285	0
Impairment of DogHero investment	0	2,000	2,080	0	0
Changes in operating assets and liabilities:
Accounts receivable	(4,925)	590	(519)	(1,760)	(151)
Prepaid expenses and other current assets	(3,923)	588	460	(935)	(1,376)
Other noncurrent assets	(33)	0	(59)	(117)	9
Accounts payable	2,174	(3,919)	(4,437)	887	4,700
Accrued expenses and other current liabilities	2,069	(4,758)	(3,177)	666	1,675
Deferred revenue			(1,736)	518	870
Pet parent deposits			(13,508)	2,648	5,738
Other noncurrent assets	21,658	(807)
Pet service provider liabilities	3,603	(13,962)	(5,320)	2,846	3,401
Accrued expenses and other current liabilities	(1,637)	(5,297)
Other noncurrent liabilities	124	1,989	1,752	4,880	140
Net cash provided by (used in) operating activities	20,606	(52,693)	(56,955)	(24,721)	(34,063)
INVESTING ACTIVITIES
Purchase of property and equipment	(564)	(734)	(910)	(16,367)	(1,159)
Capitalization of internal-use software	(4,602)	(5,214)	(6,757)	(11,906)	(6,185)
Net cash used in acquisition of Barking Dog Ventures, Ltd.			0	0	(14,100)
Proceeds from disposal of property and equipment	19	0
Purchases of available-for-sale securities	0	(16,286)	(16,286)	(72,299)	(110,021)
Proceeds from sales of available-for-sale securities	0	28,002	29,002	22,356	0
Maturities of available-for-sale securities	0	21,450	23,450	97,933	89,473
Purchase of Series C preference shares of DogHero Ltd.			0	(5,000)	0
Proceeds from sale of DogHero investment			2,920	0	0
Repayment of note receivable			0	0	3,000
Net cash provided by (used in) investing activities	(5,147)	27,218	31,419	14,717	(38,992)
FINANCING ACTIVITIES
Proceeds from issuance of redeemable convertible preferred stock, net			0	0	123,655
Proceeds from exercise of common stock options	3,339	441	788	773	726
Taxes paid related to net share settlement of equity awards	(6,719)	0
Proceeds from reverse recapitalization and related financing	268,282	0
Payment of deferred transaction costs related to reverse recapitalization	(32,743)	0
Proceeds from borrowing on credit facilities	0	64,282	64,563	0	0
Repayment of borrowings on credit facilities	(38,124)	(26,439)	(26,439)	0	0
Issuance costs related to debt financing			(281)	0	(207)
Net cash provided by financing activities	194,035	38,284	38,631	773	124,174
Effect of exchange rate changes on cash and cash equivalents	(15)	(11)	99	(70)	44
Net increase (decrease) in cash and cash equivalents	209,479	12,798	13,194	(9,301)	51,163
Cash and cash equivalents, beginning of year	80,848	67,654	67,654	76,955	25,792
Cash and cash equivalents, end of year	290,327	80,452	80,848	67,654	76,955
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for income taxes	7	278	282	7	7
Cash paid for interest	2,511	1,504	2,073	19	83
Purchase of property and equipment in accounts payable and accrued liabilities	0	18
Right-of-use asset obtained in exchange for lease liabilities	766	0
Conversion of redeemable convertible preferred stock to common stock	290,427	0
Earnout liability recognized upon the closing of the reverse recapitalization	228,082	0
Derivative warrant liabilities recognized upon the closing of the reverse recapitalization	22,032	0
Reclassification of earnout liability to additional paid-in capital upon settlement	33,010	0
NON-CASH INVESTING AND FINANCING ACTIVITIES
Issuance of Series G redeemable convertible preferred stock and common stock for acquisition of Barking Dog Ventures, Ltd.			0	0	14,311
Issuance of common stock warrants under credit facility and subordinated credit facility agreements	0	657	657	234	50
Issuance of Series G redeemable convertible preferred stock to settle Barking Dog Ventures, Ltd. Holdback	0	62	62	3,633	0
Cash and cash equivalents	290,327	80,418	80,848	67,654
Restricted cash included in prepaid expenses and other current assets	0	34
Total cash, cash equivalents and restricted cash	$ 290,327	$ 80,452	$ 80,848	$ 67,654	$ 76,955

Organization and Description of

Organization and Description of Business	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business A Place for Rover, Inc., (the “Company”) a Delaware corporation, was incorporated on June 16, 2011 and is headquartered in Seattle, Washington, with offices in Spokane, Washington and internationally in Barcelona, Spain. The Company provides an online marketplace and other related tools, support and services that pet parents and pet service providers can use to find, communicate with, and interact with each other. In October 2018, the Company acquired all of the outstanding shares of Barking Dog Ventures, Ltd. (“DogBuddy”) to accelerate its presence and expand its growth in Europe. On February 10, 2021, the Company entered into a Business Combination Agreement and Plan of Merger (the “Business Combination Agreement”) with Nebula Caravel Acquisition Corp. (“Caravel”) and Fetch Merger Sub, Inc. (“Merger Sub”), a wholly owned subsidiary of Caravel. Pursuant to the terms of the Business Combination Agreement, Merger Sub was to merge with and into the Company (collectively with other transactions described in the Business Combination Agreement, the “Merger”). On July 30, 2021 (the “Closing Date”), Merger Sub merged with and into the Company, with the Company surviving as a wholly owned subsidiary of Caravel. At the Closing Date, Caravel was renamed “Rover Group, Inc.” The Company raised (1) $268.3 million of gross proceeds from the contribution of $128.3 million of net cash held in Caravel’s trust account from its initial public offering, in addition, as part of the Merger, (2) certain investors purchased an aggregate of 5,000,000 shares of Caravel Class A Common Stock at a purchase price per share of $10.00 and an aggregate purchase price of $50,000,000 (the “PIPE Investment”) and (3) $90.0 million from the sale of an aggregate of 9,000,000 shares of Class A common stock at $10.00 per share pursuant to the backstop subscription agreement with affiliates (and an assignee of such affiliates) of the sponsor of Caravel (the “Sponsor Backstop Subscription Agreement”). Immediately before the Merger, all of the Company’s outstanding warrants were net exercised for shares of Company common stock. Upon the consummation of the Merger, all holders of Company common stock and preferred stock received shares of Caravel Class A Common Stock at a deemed value of $10.379 per share after giving effect to the applicable exchange ratio based on the completion of the following transactions contemplated by the Business Combination Agreement, as amended: • the conversion of all outstanding shares of Company redeemable convertible preferred stock into shares of Company common stock at the then-effective conversion rate as calculated pursuant to Company’s certificate of incorporation; • the cancellation of each issued and outstanding share of Company common stock (including shares of common stock resulting from the conversion of Company redeemable convertible preferred stock) and the conversion into a number of shares of Caravel Class A Common Stock equal to an exchange ratio of 1.0379 (‘the “Exchange Ratio” ; and • the conversion of all outstanding vested and unvested Company stock options into options exercisable for shares of Caravel Class A Common Stock with the same terms except for the number of shares exercisable and the exercise price, each of which were adjusted using an exchange ratio of 1.2006. The Merger is accounted for as a reverse recapitalization under U.S. GAAP. For accounting purposes, the financial statements of the Rover Group, Inc. will represent a continuation of the financial statements of the Company with the Merger treated as the equivalent of the Company issuing stock for the net assets of Caravel, accompanied by a recapitalization. Accordingly, for periods prior to the Merger, the reported share and per share amounts have been retroactively converted by applying the Exchange Ratio. Issued and outstanding shares as disclosed herein have been adjusted reflecting the Exchange Ratio. Authorized shares of redeemable convertible preferred stock of 87,611,000 and Legacy Rover common stock of 144,250,000 shares authorized for issuance reflect the amounts legally authorized without giving effect to the applicable exchange ratio. Impact of COVID-19 On March 11, 2020, the World Health Organization declared the novel strain of coronavirus that causes the disease COVID-19 a global pandemic and recommended containment and mitigation measures worldwide, including travel restrictions and business slowdowns or shutdowns in affected areas. As a result, there has been a significant decline in demand for pet services. As a result of these developments, the Company experienced an unfavorable impact on its revenue, results of operations and cash flows in 2020 and to date in 2021. The Company may face longer term impact from COVID-19 due to, among other factors, evolving federal, state and local restrictions and shelter-in-place orders, changes in consumer behavior and health concerns which may impact customer demand and availability of pet service providers. The current events and economic conditions are significant in relation to the Company’s ability to fund its business operations. In response to the impact of COVID-19, the Company implemented a number of measures to minimize cash outlays, including reducing discretionary marketing and other expenses and implementing a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company incurred severance-related and legal costs, and modified the terms of stock options previously awarded to impacted employees. Additionally, in March 2020, the Company borrowed $11.4 million and $15.0 million under the revolving loan and growth capital advance components, respectively, of the credit facility, and $30.0 million under the subordinated credit facility (see Note 9—Debt). In April 2020, the Company was approved for and received a $8.1 million loan from the Small Business Administration’s Paycheck Protection Program (see Note 9—Debt). Liquidity The Company has incurred losses and negative cash flows from operations and had an accumulated deficit of $256.3 million as of December 31, 2020. The Company has primarily funded its operations with proceeds from the issuance of redeemable convertible preferred stock and other equity transactions, debt borrowings, and with customer payments. Management expects operating losses and negative cash flows from operations to continue in the foreseeable future as the Company continues to invest in expansion activities. Management believes that the Company’s current cash and cash equivalents will be sufficient to fund its operations for at least the next 12 months from the issuance of these consolidated financial statements. The Company’s assessment of the period of time through which its financial resources will be adequate to support its operations is a forward-looking statement and involves risks and uncertainties. The Company’s actual results could vary as a result of its near and long-term future capital requirements that will depend on many factors including its growth rate. The Company has based its estimates on assumptions that may prove to be wrong, and it could use its available capital resources sooner than its currently expects. The Company may be required to seek additional equity or debt financing. In the event that additional financing is required from outside sources, the Company may not be able to raise it on acceptable terms or at all. If the Company is unable to raise additional capital when desired, or if it cannot expand its operations or otherwise capitalize on its business opportunities because it lacks sufficient capital, its business, operating results, and financial condition would be adversely affected (see Note 18—Subsequent Events). Rover Group, Inc. (formerly known as Nebula Caravel Acquisition Corp.) and its wholly owned subsidiaries (collectively “Rover” or the “Company”) is headquartered in Seattle, Washington, with offices in Spokane, Washington and internationally in Barcelona, Spain. The Company provides an online marketplace and other related tools, support and services that pet parents and pet service providers can use to find, communicate with, and interact with each other. On July 30, 2021 (the “Closing Date” or “Closing”), Nebula Caravel Acquisition Corp. (“Caravel”) consummated the previously announced merger pursuant to a Business Combination Agreement and Plan of Merger, dated February 10, 2021 (the “Business Combination Agreement”), by and between Caravel, Fetch Merger Sub, Inc., a wholly owned subsidiary of Caravel (“Merger Sub”), and A Place for Rover, Inc. (hereinafter referred to as “Legacy Rover”). Pursuant to the terms of the Business Combination Agreement, Merger Sub merged with and into Legacy Rover, with Legacy Rover continuing as the surviving entity and as a wholly owned subsidiary of Caravel (together with the other transactions described in the Business Combination Agreement, the “Merger”). On the Closing Date, Caravel changed its name from Nebula Caravel Acquisition Corp. to “Rover Group, Inc.” See Note 3—Reverse Recapitalization for additional information. Impact of COVID-19 On March 11, 2020, the World Health Organization declared the novel strain of coronavirus that causes the disease COVID-19 a global pandemic and recommended containment and mitigation measures worldwide, including travel restrictions and business slowdowns or shutdowns in affected areas. As a result, there was a significant decline in demand for pet services. As a result of these developments, the Company experienced an unfavorable impact on its revenue, results of operations and cash flows in 2020 and in some of the periods to date in 2021. The COVID-19 pandemic event and economic conditions were significant in relation to the Company’s ability to fund its business operations. In response to the impact of COVID-19, the Company implemented a number of measures to minimize cash outlays, including reducing discretionary marketing and other expenses and implemented a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company incurred severance-related and legal costs, and modified the terms of stock options previously awarded to impacted employees. The ongoing COVID-19 pandemic continues to impact communities globally, including in the markets we serve in the United States, Canada and Europe. The restrictive measures have not only negatively impacted consumer and business spending habits, but they have also adversely impacted, and may further impact, our workforce and operations. Although certain of these measures have now eased in some geographic regions, overall measures to contain the COVID-19 outbreak may remain in place for a significant period of time as many geographic regions are experiencing a resurgence of COVID-19 infections, as well as new variants of the virus, such as the Delta variant. The duration and severity of this pandemic, including new variants, are unknown, and the extent of the business disruption and financial impact depend on factors beyond our knowledge and control. Liquidity On July 30, 2021, the Company completed the Merger and received net proceeds of $235.6 million, net of transaction costs of $32.7 million. See Note 3—Reverse Recapitalization for additional information. The Company has incurred losses from operations and had an accumulated deficit of $354.2 million as of September 30, 2021. The Company has primarily funded its operations with proceeds from the issuance of redeemable convertible preferred stock, common stock and other equity transactions, proceeds from the Merger, debt borrowings, and with customer payments. As the Company continues to invest in expansion activities,

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation and Basis of Presentation The consolidated financial statements and accompanying notes include the accounts of the Company and its wholly owned subsidiaries, after elimination of all intercompany balances and transactions. The Company has prepared the consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated balance sheet and the reported amounts of revenue and expenses during the reporting period. Significant items subject to such estimates and assumptions, include, but are not limited to, the capitalization and estimated useful life of the Company’s internal-use software development costs and the assumptions used in the valuation of common and preferred stock. These estimates and assumptions are based on information available as of the date of the consolidated financial statements; therefore, actual results could differ from management’s estimates. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. The Company adjusts such estimates and assumptions when facts and circumstances dictate. Changes in those estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods. As future events and their effects cannot be determined with precision, actual results could materially differ from those estimates and assumptions. Net Loss per Share Attributable to Common Stockholders The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. The Company’s redeemable convertible preferred stock contractually entitles the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in the Company’s losses. As such, net losses for the periods presented were not allocated to these securities. Basic net loss per share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is the same as basic net loss per share for each period presented since the effects of potentially dilutive securities are antidilutive given the Company’s net loss. Segment Information The Company has one operating segment and one reportable segment. As the Company’s chief operating decision maker, the Chief Executive Officer reviews financial information on a consolidated basis for purposes of allocating resources and evaluating financial performance. Substantially all long-lived assets are located in the United States and substantially all revenue is attributed to fees from pet parents and pet service providers based in the United States. Foreign Currencies The functional currency for the Company’s foreign subsidiaries is either the U.S. dollar or the local currency depending on the assessment of management. An entity’s functional currency is determined by the currency of the economic environment in which the majority of cash is generated and expended by the entity. The financial statements of all majority-owned subsidiaries and related entities with functional currencies other than the U.S. dollar have been translated into U.S. dollars. All assets and liabilities of the respective entities are translated at year-end exchange rates and all revenue and expenses are translated at average rates during the respective period. Translation adjustments are reported as other comprehensive income (loss) in the consolidated statements of comprehensive loss. Foreign currency transaction gains and losses are a result of the effect of exchange rate changes on transactions denominated in currencies other than the functional currency, including U.S. dollars. Gains and losses on those foreign currency transactions are included in determining net loss for the period of exchange and are recorded in other income (expense), net in the consolidated statements of operations. The net effect of foreign currency gains and losses was not material for any of the periods presented. Certain Significant Risks and Uncertainties The Company is subject to certain risks and challenges associated with other companies at a similar stage of development, including risks associated with: dependence on key personnel; marketing; adaptation to changing market dynamics and customer preferences; and competition including from larger companies that may have greater name recognition, longer operating histories, more and better established customer relationships and greater resources than the Company. The Company’s ability to provide a reliable platform largely depends on the efficient and consistent operation of its computer information systems and those of its third-party service providers. Any significant interruptions could harm the Company’s business and reputation and result in a loss of business. Further, there has been evidence that the Company has been the subject of cyber-attacks, and it is possible that it will be subject to similar attacks in the future. These attacks may be primarily aimed at interrupting the Company’s business, exposing it to financial losses, or exploiting information security vulnerabilities. To management’s knowledge, no prior attacks or breaches have, individually, or in the aggregate, resulted in any material liability to the Company, any material damage to its reputation, or any material disruption to the Company’s business. See Note 18—Subsequent Events for management’s evaluation of events that occurred subsequent to December 31, 2020 and through the issuance of these consolidated financial statements. Cash and Cash Equivalents The Company considers all highly liquid investments with stated maturities of three months or less from the date of purchase to be cash equivalents. As of December 31, 2019, and 2020, cash equivalents primarily consisted of money market fund investments. Accounts Receivable Accounts receivable primarily include funds collected by payment processors on the Company’s behalf from pet parents and pet service providers, net of an allowance for doubtful accounts. Bad debt expense and the allowance for doubtful accounts were not material for any of the periods presented. Short-term Investments The Company classifies its investments in debt securities as available-for-sale. Investment securities are stated at fair value with any unrealized gains or losses included as a component of accumulated other comprehensive income (loss) in stockholders’ deficit. Realized gains and losses and declines in the value of securities judged to be other-than-temporary are included in other income (expense), net in the consolidated statements of operations. The Company regularly reviews investments for other-than-temporary impairment using both qualitative and quantitative criteria. When assessing short-term investments for other-than-temporary declines in value, the Company considers factors such as, among other things, the extent and length of time the investment’s fair value has been lower than its cost basis, the financial condition and near-term prospects of the investee, the Company’s ability and intent to retain the investment for a period of time sufficient to allow for any anticipated recovery in fair value, and the expected cash flows from the security. If any adjustment to fair value reflects a decline in the value of the investment that the Company considers to be “other than temporary,” the Company reduces the investment to fair value through a charge to the consolidated statements of operations and consolidated statements of comprehensive loss. No such adjustments were necessary during the periods presented. The cost of investments for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Dividend and interest income, and any amortization of premiums and accretion of discounts to maturity are included in interest income, net in the consolidated statement of operations. The Company considers all available-for-sale debt securities, including those with maturity dates beyond 12 months, as available to support current operational liquidity needs, and therefore, classifies all securities that are not classified as cash and cash equivalents as current assets in the consolidated balance sheets. The interest earned on short-term investments is recorded in interest income in the consolidated statements of operations. Concentrations of Credit Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, consist of cash, investments and accounts receivable. The Company maintains cash balances that may exceed the insured limits set by the Federal Deposit Insurance Corporation. The Company reduces credit risk by placing cash balances with major financial institutions throughout the United States that management assesses to be of high-credit quality. For the years ended December 31, 2018, 2019 and 2020, no individual pet service provider, pet parent, or affiliate represented 10% or more of the Company’s revenue. As of December 31, 2019 and 2020, accounts receivable was $2.5 million and $3.0 million, respectively, and was comprised primarily of amounts due from payment processors who collected payment from pet parents on behalf of the Company. Comprehensive Loss Certain gains and losses are recognized in comprehensive loss but excluded from net loss. Comprehensive loss includes net loss, unrealized gains and losses on available-for-sale debt securities and foreign currency translation adjustments. Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels that are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1— Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2— Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3— Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the specific asset or liability. The Company recognizes transfers between levels within the fair value hierarchy, if any, at the end of each period. There were no transfers between levels during the periods presented. The carrying values of the Company’s cash equivalents, accounts receivable, accounts payable, and accrued expenses and other current liabilities approximate fair value based on the highly liquid, short-term nature of these instruments. The carrying amount of the Company’s outstanding debt approximates the fair value as the debt bears a floating rate that approximates the market interest rate. Property and Equipment, net Property and equipment are stated at cost and are depreciated or amortized using the straight-line method over the estimated useful lives of the assets. Depreciation provisions are based upon the following estimated useful lives: Asset Category Depreciation Period Computers 3 years Furniture and fixtures 5-7 years Leasehold improvements Shorter of estimated useful life of asset or remaining lease term Upon retirement or sale, the cost of disposed assets, and the related accumulated depreciation, is removed from the accounts and any resulting gain or loss is reflected in other income (expense), net in the consolidated statements of operations. Expenditures for maintenance and repairs are charged to expense as incurred, whereas additions and improvements that increase the value or extend the life of an asset are capitalized to property and equipment. Leasehold improvements include enhancements made to the Company’s leased office spaces (primarily in Seattle, Washington). Internal-Use Software Costs incurred to develop the Company’s website and software for internal use are capitalized and amortized over its estimated useful life. Capitalization of costs to develop software begin when preliminary development efforts are successfully completed, management has authorized and committed project funding and it is probable that the project will be completed, and the software will be used as intended. The Company also capitalizes costs related to upgrades and enhancements when it is probable the expenditures will result in significant additional functionality or will extend the useful life of existing functionality. Costs related to the design or maintenance of website development and internal-use software are expensed as incurred. The Company periodically reviews website development and internal-use software costs to determine whether the projects will be completed, placed in service, removed from service or replaced by other internally developed or third-party software. If the asset is not expected to provide any future use, the asset is retired, and any unamortized cost is expensed. Internal-use software is amortized on a straight-line basis over its estimated useful life, generally three years. Management evaluates the useful lives of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets. Management has determined that there has been no impairment of previously capitalized costs during 2018, 2019 and 2020. The Company capitalized $6.2 million, $11.9 million and $7.0 million of software development costs during the years ended December 31, 2018, 2019 and 2020, respectively. Stock-based compensation costs included in capitalized internal-use software development costs were not material for the years ended December 31, 2018, 2019 and 2020. The Company recorded amortization expense for capitalized internal use software of $2.5 million, $5.2 million and $7.2 million for the years ended December 31, 2018, 2019 and 2020, respectively, which is included in cost of revenue (exclusive of depreciation and amortization shown separately) in the consolidated statements of operations. Capitalized website development and internal-use software costs are included in property and equipment, net in the consolidated balance sheets. Business Combinations The results of businesses acquired in a business combination are included in the Company’s consolidated financial statements from the date of acquisition. The Company allocates the purchase price of a business combination, which is the sum of the consideration provided and may consist of cash, equity or a combination of the two, to the identifiable assets acquired and liabilities assumed of the acquired business at their acquisition date fair values. The excess of the purchase price over the amount allocated to the identifiable assets and liabilities, if any, is recorded as goodwill. Determining the fair value of assets acquired and liabilities assumed requires management to use judgment and estimates, including the selection of valuation methodologies, cost of capital estimates of future revenue and cash flows, discount rates, and selection of comparable companies, among others. The Company’s estimates of fair value are based on assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. During the measurement period, not to exceed one year from the date of acquisition, the Company may record adjustments to the assets acquired and liabilities assumed, with a corresponding offset to goodwill. When the Company issues stock-based or cash awards to an acquired company’s stockholders, the Company evaluates whether the awards are contingent consideration or compensation for post-combination services. The evaluation includes, among other things, whether the vesting of the awards is contingent on the continued employment of the acquired company’s stockholder beyond the acquisition date. If continued employment is required for vesting, the awards are treated as compensation for post-combination services and recognized as expense over the requisite service period. Acquisition-related transaction costs are expensed in the period in which the costs are incurred and included in general and administrative expense in the Company consolidated statements of operations. Goodwill Goodwill represents the excess of the aggregate fair value of the consideration transferred in a business combination over the fair value of the assets acquired, net of liabilities assumed. Goodwill is not amortized, but is subject to an annual impairment test. Management has determined that the Company has a single reporting unit and performs its annual goodwill impairment test as of October 31, or more frequently if events or changes in circumstances indicate that the goodwill may be impaired. Events or changes in circumstances which could trigger an impairment review include significant changes in the manner of the Company’s use of the acquired assets or the strategy for the Company’s overall business, significant negative industry or economic trends, significant underperformance relative to historical or projected future results of operations, a significant adverse change in the business climate, cost factors that have a negative effect on earnings and cash flows, an adverse action or assessment by a regulator, estimated per share fair value of common stock, unanticipated competition or a loss of key personnel. The Company has the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is not more-likely-than-not that the fair value of the reporting unit is less than its carrying amount, then additional impairment testing is not required. However, if the Company concludes otherwise, then it is required to perform a quantitative assessment for impairment. The quantitative assessment involves comparing the estimated fair value of the reporting unit with its respective book value, including goodwill. If the estimated fair value exceeds book value, goodwill is considered not to be impaired and no additional steps are necessary. If, however, the book value of the reporting unit exceeds the fair value, an impairment loss is recognized in an amount equal to the excess, not to exceed the total amount of goodwill allocated to that reporting unit. The Company completed a qualitative analysis as of October 31, 2018 and 2019. The Company experienced significant disruption to its business in 2020 as a result of the rapid development of COVID-19 and the corresponding reduction in the demand for its marketplace services. The Company completed qualitative analyses as of March 31, 2020, June 30, 2020, September 30, 2020, and October 31, 2020. No impairment of goodwill was recognized during any of the periods presented. Intangible Assets Intangible assets are amortized over the estimated useful life of the assets. Amortization of intangible assets associated with or used in the services provided by the Company from which it generates revenue are classified within cost of revenue (exclusive of depreciation and amortization shown separately) in the Company’s statements of operations. Amortization of intangible assets not associated with or used in the services provided by the Company from which it generates revenue are classified within depreciation and amortization expense within the Company’s statements of operations. For the periods presented, amortization of the Company’s capitalized internal-use software costs related to its online platform has been included within costs of revenues. For the periods presented, amortization expense related to other intangible assets have been classified within depreciation and amortization within the Company’s statement of operations. The Company reviews intangible assets for impairment under the long-lived asset model described below. No impairment of intangible assets was recorded during any of the periods presented. The Company identified certain intangible assets, consisting of technology and tradenames, as defensive assets. These are assets that the Company acquired but does not intend to actively use. Rather, the Company intends to hold the assets to prevent others from obtaining access to the assets. Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be fully recoverable. When such events occur, management determines whether there has been impairment by comparing the anticipated undiscounted future net cash flows to the carrying value of the asset or asset group. If impairment exists, the assets are written down to its estimated fair value. There was no impairment of long-lived assets for any of the periods presented. Revenue Recognition (Topic 606) The Company operates an online marketplace that provides a platform for pet parents and pet service providers to communicate and arrange for pet services. The Company derives its revenue principally from pet parents’ and pet service providers’ use of the Company’s platform and related services that enable pet service providers to offer, book and fulfill pet services. Additionally, the Company earns revenue from fees paid by pet service providers for background checks in order to use the Company’s platform. The Company enters into terms of service with pet service providers and pet parents who wish to use the Company’s platform. The terms of service define the pet service providers’ rights and responsibilities when using the Company’s platform as well as general payment terms. The Company charges a fixed percentage service fee for each arrangement of pet services between the pet parent and the pet service provider on the Company’s platform (a booking). The fixed percentage service fees are established at the time a pet parent or pet provider joined the platform and do not vary based on the volume of transactions. A booking defines the explicit fee from which the Company earns its fixed percentage service fee. The creation of a booking combined with the terms of service establish enforceable rights and obligations for the transaction. A contract exists between the pet service provider and the Company upon the creation of a booking and after the pet service providers’ cancellation period has lapsed. Pet parents are considered the Company’s customers to the extent that they pay a fixed percentage fee to the Company for the booking. Similarly, a contract exists between the pet parent and the Company upon the creation of a booking and after the pet service providers’ cancellation period has lapsed. Pet parents pay for services at the time of booking. The Company considers the facilitation of the connection between pet service provider and pet parent to be the promise in the contracts. This is consistent with the terms of service, as well as the substance of what a pet service provider or pet parent is expecting from the use of the Company’s platform. While customers have access to the use of the platform, customer support, and other activities, these activities are not considered distinct from each other in the context of the overall arrangement, which is the facilitation of a connection between a pet service provider and a pet parent. As such, the Company has determined that its sole performance obligation is to facilitate a connection between pet service providers and pet parents through its platform. The Company’s performance obligation is satisfied at a point-in-time when the connection has been completed, which is when the pet service provider and pet parent have completed a booking, any related cancellation period has lapsed, and the related underlying pet services have begun. The Company derives revenue from pet service providers and pet parents primarily in the United States, as well as Canada and Europe. Revenue related to background checks is recorded upon completion of the related background check. From time to time, the Company issues credits or refunds to its pet parents or pet service providers as a result of customer satisfaction matters. Such amounts have historically been immaterial. Judgment is required in determining whether the Company is the principal or agent in transactions with pet service providers and pet parents. The Company evaluates the presentation of revenue on a gross or net basis based on whether it controls the service provided to the pet parent and is therefore the principal, or the Company arranges for other parties to provide the service to the pet parent and is therefore the agent. The Company has concluded it is the agent in transactions with pet service providers and pet parents because, among other factors, it is not responsible for the delivery of pet services provided by the pet service provider to the pet parent. Accordingly, the Company recognizes revenue on a net basis, representing the fee the Company expects to receive in exchange for providing the access to the Company’s platform to pet service providers and pet parents. The Company has no significant financing components in its contracts with customers. The Company recognizes revenue net of any sales tax paid related to its revenue transactions. Revenue Recognition (Prior to adoption of Topic 606) The Company recognizes revenue when (i) persuasive evidence of an arrangement exists, (ii) services provided by the Company have been rendered, (iii) the amount of fees to be paid by the Company’s customer is fixed or determinable, and (iv) the collection of fees is reasonably assured. Revenue related to marketplace services is recognized as the Company’s services are provided when the pet service provider and pet parent have completed a booking, any related cancellation period has lapsed, and the related underlying pet service have begun. Revenue related to background checks is recorded upon completion of the related background check. The Company evaluates whether it is appropriate to recognize revenue on a gross or net basis based upon its evaluation of whether it is the primary obligor in a transaction, has inventory risk and has latitude in establishing pricing and selecting suppliers, among other factors. The Company primarily derives revenue from two sources: 1) percentage-based fees charged to pet service providers for services that were arranged on the marketplace, and 2) percentage-based fees charged to pet parents for services arranged on the marketplace. Revenue related to these fees is recognized ratably over the period pet services are provided, which matches the Company’s obligation to provide support to both pet parents and pet service providers over the service period. Pet Parent Discounts The Company offers discounts to pet parents to encourage use of the Company’s platform. Discounts are primarily in the form of coupon codes for prospective pet parents and are accounted for as reductions to revenue. Deferred Revenue Deferred revenue represents payment received from pet parents in advance of the related performance obligation being satisfied and revenue being recognized and could be subject to return to pet parents upon the cancellation of the booking prior to fulfilment of the Company’s performance obligation based on the applicable terms of service. Pet Parent Deposits and Pet Service Provider Liabilities The Company records payments received from pet parents, excluding the revenue portion due to the Company, in advance of the related services being provided as pet parent deposits. As the related performance obligations are satisfied, these amounts are reclassified from pet parent deposits to pet service provider liabilities in the consolidated balance sheets. The Company is subject to compliance with escheat laws applicable by jurisdiction where pet service providers do not claim the amounts owed to them for services rendered. Cost of Revenue (Exclusive of Depreciation and Amortization Shown Separately) Cost of revenue (exclusive of depreciation and amortization shown separately) includes fees paid to payment processors for credit card and other funding transactions, server hosting costs, internal-use software amortization, third-party costs for background checks for pet care providers, claim costs paid out under the Rover Guarantee (“Rover Guarantee”) and other direct and indirect costs arising as a result of bookings that take place on our platform. Operations and Support Operations and support expenses include payroll, employee benefits, stock-based compensation and other personnel-related costs associated with the Company’s operations and support team, and third-party costs related to outsourced support providers. This team assists with onboarding new pet care providers, quality reviews of pet care provider profiles, fraud monitoring and prevention across our marketplace, and community support provided via phone, email, and chat to our pet parents and pet care providers. This support includes assistance and responding to pet parents’ inquiries regarding the general use of our platform or how to make or modify a booking through our platform. The Company allocates a portion of overhead costs which includes lease expense, utilities and information technology expense to operations and support expense based on headcount. Marketing Marketing expenses include payroll, employee benefits, stock-based compensation expenses and other personnel-related costs associated with the Company’s marketing team. These expenses also include digital marketing, brand marketing, public relations, broadcast television, marketing partnerships and other promotions. Digital marketing primarily consists of targeted promotional campaigns through electronic channels, such as social media, search engine marketing, affiliate programs and display advertising, all of which are primarily focused on pet parent acquisition and brand marketing. Except for content creation, advertising expenses are expensed as incurred, and are included in marketing expenses on the consolidated statements of operations. The Company allocates a portion of overhead costs which includes lease expense, utilities and information technology expense to marketing expense based on headcount. Advertising expenses were $47.6 million, $37.9 million and $8.1 million during the years ended December 31, 2018, 2019 and 2020, respectively. Product Development Product development expenses include payroll, employee benefits, stock-based compensation e

Reverse Recapitalization

Reverse Recapitalization	9 Months Ended
	Sep. 30, 2021
Reverse Recapitalization [Abstract]
Reverse Recapitalization	Reverse Recapitalization In connection with the Merger, the Company raised $268.3 million of gross proceeds from (1) the contribution of $128.3 million of net cash held in Caravel’s trust account from its initial public offering, (2) $50.0 million from the sale of 5,000,000 shares of Class A common stock at $10.00 per share in a transaction exempt from the registration requirement of the Securities Act of 1933, and (3) $90.0 million from the sale of an aggregate of 9,000,000 shares of Class A common stock at $10.00 per share pursuant to the backstop subscription agreement with affiliates (and an assignee of such affiliates) of the sponsor of Caravel (the “Sponsor Backstop Subscription Agreement”). Immediately before the Merger, all of Legacy Rover’s outstanding warrants were net exercised for shares of Legacy Rover common stock. Upon the consummation of the Merger, all holders of Legacy Rover common stock and preferred stock received shares of our Class A Common Stock at a deemed value of $10.379 per share after giving effect to the applicable exchange ratio based on the completion of the following transactions contemplated by the Business Combination Agreement: • the conversion of all outstanding shares of Legacy Rover redeemable convertible preferred stock into shares of Legacy Rover common stock at the then-effective conversion rate as calculated pursuant to Legacy Rover’s certificate of incorporation; • the cancellation of each issued and outstanding share of Legacy Rover common stock (including shares of common stock resulting from the conversion of Legacy Rover redeemable convertible preferred stock) and the conversion into a number of shares of our Class A Common Stock equal to an exchange ratio of 1.0379 (“Exchange Ratio”); and • the conversion of all outstanding vested and unvested Legacy Rover stock options into options exercisable for shares of our Class A Common Stock with the same terms except for the number of shares exercisable and the exercise price, each of which were adjusted using the exchange ratio of 1.2006. No cash consideration was paid out to Legacy Rover stockholders as there was insufficient cash after Caravel common stockholders exercised their right to redeem shares for cash. In connection with the Merger, the Company incurred $32.7 million of transaction costs. These costs consisted of underwriting, legal, and other professional fees, of which $14.5 million was recorded to additional paid-in capital and the remaining $18.2 million related to liabilities assumed from Caravel that were settled immediately after Closing. The number of shares of Class A common stock issued immediately following the consummation of the Merger at July 30, 2021 was: Number of Shares Common stock of Caravel outstanding prior to the Merger 27,500,000 Less redemption of Caravel shares (14,677,808) Caravel Sponsor Earnout Shares outstanding prior to the Merger 6,875,000 Less forfeiture of Caravel Sponsor Earnout Shares(1) (975,873) Common stock of Caravel (1) 18,721,319 Shares issued in PIPE financing 5,000,000 Shares issued in Sponsor Backstop Subscription Agreement 8,000,000 Shares issued in Assignment Agreement 1,000,000 Merger and PIPE financing shares 32,721,319 Legacy Rover shares (2) 124,477,819 Total 157,199,138 __________ (1) Upon the Merger closing, 3,437,500 Sponsor Earnout Shares vested, 975,873 were forfeited and 2,461,627 Sponsor Earnout Shares remained outstanding and unvested. At Closing, the remaining 2,461,627 Sponsor Earnout Shares were subject to vesting conditions based upon the occurrence of certain triggering events. At the close of trading on September 29, 2021, pursuant to the Business Combination Agreement and the achievement of Trigger Events I and II, 1,969,300 Founder Shares vested. (2) The number of Legacy Rover shares was determined from the 32,434,987 shares of Legacy Rover common stock and 87,496,938 shares of Legacy Rover redeemable convertible preferred stock outstanding, which were converted to an equal number of shares of Legacy Rover common stock upon the closing of the Merger, and then converted at the Exchange Ratio of 1.0379 to Class A common stock of the Company. All fractional shares were rounded down to the nearest whole share. The Merger was accounted for as a reverse recapitalization under GAAP because Legacy Rover has been determined to be the accounting acquirer under Financial Accounting Standards Board’s Accounting Standards Codification (“ASC”) Topic 805, Business Combinations. Under this method of accounting, Caravel was treated as the “acquired” company for financial reporting purposes. Accordingly, for accounting purposes, the financial statements of the Company will represent a continuation of the financial statements of Legacy Rover with the Merger treated as the equivalent of Legacy Rover issuing stock for the net assets of Caravel, accompanied by a recapitalization. The net assets of Caravel are stated at historical cost, with no goodwill or other intangible assets recorded. Operations prior to the Merger are those of Legacy Rover. Legacy Rover was determined to be the accounting acquirer based on evaluation of the following facts and circumstances: • Legacy Rover stockholders comprising a relative majority of the voting power of Rover; • Legacy Rover will have the ability to nominate a majority of the members of the board of directors of Rover; • Legacy Rover’s operations prior to the acquisition comprising the only ongoing operations of Rover; • Legacy Rover’s senior management comprising a majority of the senior management of Rover; and • Rover substantially assuming the Legacy Rover name.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Business Combinations	3. Business Combinations On October 31, 2018, the Company acquired all of the outstanding shares of DogBuddy in exchange for the issuance of 1.4 million shares of the Company’s common stock, 1.9 million shares of the Company’s Series G redeemable convertible preferred stock, which includes a holdback of 539,000 shares of Series G preferred stock, and cash payment of $19.4 million to the stockholders of DogBuddy. The aggregate estimated value of the consideration described above, on the date of the acquisition was $37.6 million. The estimated fair value of the Series G preferred stock issued for the DogBuddy acquisition was $10.0 million. The Company, as acquirer, retained a holdback of Series G preferred stock for up to a one-year period as partial security against certain indemnity obligations. The holdback has an estimated fair value of $3.9 million based on the recent transaction price of the Company’s Series G redeemable convertible preferred stock and was recorded to accrued expenses and other current liabilities in the consolidated balance sheets. In connection with the acquisition of DogBuddy, the Company also assumed outstanding options to purchase shares of DogBuddy’s capital stock, which were converted into options to purchase an additional 67,000 shares of the Company’s common stock. In May 2017, the Company issued a note with a principal amount of $3.0 million to DogBuddy. Interest accrued on such note at a rate of 4% per year, with accrued interest payable upon maturity. In connection with the Company’s acquisition of DogBuddy on October 31, 2018, the principal amount and accrued interest was repaid in full. In November 2019, the Company released and issued 0.5 million shares of Series G preferred stock to former stockholders of DogBuddy related to the holdback. The acquisition date estimated fair value of the holdback shares issued during 2019 was $3.6 million. At December 31, 2019, the remaining holdback liability of $0.3 million was recorded in accrued expenses and other current liabilities in the consolidated balance sheets. In February 2020, final settlement of the holdback was completed through the issuance of approximately 9,000 shares of Series G preferred stock. The remaining approximately 30,000 shares were never issued and retained by the Company to cover additional expenses. The table below presents components of the purchase consideration, and the tangible and intangible assets acquired, and liabilities assumed, at fair value, in connection with the acquisition (in thousands): Assets Current assets Cash and cash equivalents $ 5,219 Accounts receivable 7 Prepaid expenses and other current assets 163 Total current assets 5,389 Property and equipment 67 Intangible assets 10,850 Goodwill 23,728 Other noncurrent assets 57 Total assets 40,091 Liabilities Current liabilities Accounts payable 28 Accrued expenses and other current liabilities 74 Deferred revenue 109 Pet parent deposits 681 Total current liabilities 892 Deferred tax liability 1,551 Total liabilities 2,443 Total consideration $ 37,648 The table below summarizes the estimated useful lives of the acquired intangible assets and the methodologies employed in determining their related estimated fair values (in thousands): Fair Value Estimated Useful Life (years) Pet parent relationships $ 6,600 8 Pet service provider relationships 2,000 3 Technologies 2,200 2 Non-competition agreements 50 1 Total intangible assets $ 10,850 Goodwill recorded in connection with the acquisition is primarily attributed to the increased geographic coverage throughout Europe and synergies gained, such as advertising purchasing power and integrated pet service provider networks. None of the resulting goodwill is deductible for tax purposes. The Company incurred $1.0 million in acquisition-related costs in the year ended December 31, 2018, which were included in general and administrative expenses in the consolidated statements of operations. An intangible asset comprised of $2.2 million of technologies represents a defensive asset as it will not be used substantially beyond the post-acquisition transition period of seven months from the date of acquisition. The Company recognized revenue of $0.3 million and net loss of $1.0 million from DogBuddy from the acquisition date to December 31, 2018 in the consolidated statements of operations for the year ended December 31, 2018. During the year ended December 31, 2019, a measurement period adjustment was made to reduce goodwill from the DogBuddy acquisition by $1.7 million primarily due to an adjustment to the deferred tax asset for pre-acquisition losses that were originally estimated to be unrealizable (see Note 8—Goodwill and Intangible Assets). There was no impact to the consolidated statements of operation for this adjustment. Unaudited Pro Forma Information The following table summarizes certain supplemental pro forma financial information for the year ended December 31, 2018 as if the acquisition of DogBuddy had occurred as of January 1, 2018 (in thousands): Year Ended December 31, 2018 As Reported Pro Forma Revenue $ 71,411 $ 73,261 Net loss (64,677) (69,962) Net loss attributable to common stockholders $ (65,168) $ (70,453) The unaudited pro forma information for the year ended December 31, 2018 reflects: (1) the elimination of $1.5 million of transaction costs related to the DogBuddy acquisition recorded in 2018 and (2) the increase of $2.2 million in amortization expense based on the fair value adjustments to the intangible assets acquired from DogBuddy. The unaudited pro forma results also include the accounting effects resulting from the acquisition of DogBuddy such as the reversal of costs related to special retention bonuses and other payments to employees and transaction costs directly related to the acquisition of DogBuddy. The unaudited pro forma financial information presented was prepared for comparative purposes only and does not purport to present what the actual results would have been had the acquisition of DogBuddy actually occurred on January 1, 2018, nor is the information intended to project results for any future period.

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Contract Balances The Company’s contract liabilities consist of deferred revenue. The changes in the Company’s contract liabilities were as follows (in thousands): Balance at December 31, 2018 $ 2,585 Revenue recognized (92,063) Bookings and other 91,966 Balance at December 31, 2019 2,488 Revenue recognized (45,585) Bookings and other 43,848 Balance at December 31, 2020 $ 751 Contract Balances The Company’s contract liabilities consist of deferred revenue. The changes in the Company’s contract liabilities were as follows (in thousands): Balance at December 31, 2020 $ 751 Bookings and other 73,900 Revenue recognized (68,648) Balance at September 30, 2021 $ 6,003 Balance at June 30, 2021 $ 8,167 Bookings and other 32,067 Revenue recognized (34,231) Balance at September 30, 2021 $ 6,003

Investments

Investments	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Investments	5. Investments Available-for-sale investments consist of fixed-income securities that are accounted for at fair value. Premiums and discounts paid on securities at the time of purchase are amortized over the period of maturity. The amortized cost and fair value of the available-for-sale investments and unrealized gains and losses were as follows (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Corporate securities and commercial paper $ 25,291 $ 64 — $ 25,355 Asset-backed securities 660 — — 660 Certificates of deposit 10,118 — — 10,118 Total $ 36,069 $ 64 — $ 36,133 There were no available-for-sale investments at December 31, 2020. There were no other-than-temporary impairments recognized in accumulated other comprehensive income during all periods presented. Realized gains and losses on sales of available-for-sale securities were not material for all periods presented. The contractual maturity of the available-for-sale investments were as follows (in thousands): December 31, 2019 Less than 1 year 1 to 5 years More than 5 years Total Corporate securities and commercial paper $ 17,187 $ 8,168 $ — $ 25,355 Asset-backed securities 0 660 0 660 Certificates of deposit 8,120 1,998 0 10,118 Total $ 25,307 $ 10,826 $ — $ 36,133 Other Investments In March 2019, the Company purchased 3.4 million Series C Preference Shares of DogHero Ltd. (“DogHero”), an online marketplace for pet services in South America, for $5.0 million. The 3.4 million shares acquired represents 17% of DogHero’s fully diluted outstanding equity. In accordance with Accounting Standards Codification (“ASC”) 321, Investments – Equity Securities, the Company elected the measurement alternative to value this equity investment without a readily determinable fair value. The carrying amount of the investment is included in other noncurrent assets in the consolidated balance sheets. In accordance with ASC 321, for each reporting period, the Company completes a qualitative assessment considering impairment indicators to evaluate whether the investment is impaired. In connection with the purchase of Series C Preference Shares, the Company also entered into a call option to purchase the remaining equity of DogHero at a defined exercise price within a two-year period after the initial investment. In July 2020, the Company received notification that a letter of intent to acquire DogHero had been submitted. The Company was provided the option of receiving cash consideration of $3.0 million or share consideration in the acquiring company. The Company determined that the letter of intent was an indicator of impairment and recorded an impairment loss of $2.0 million, reducing the carrying amount of the investment to $3.0 million. In November 2020, the Company sold its investment and call option in DogHero for $2.9 million. As such, the Company recorded an additional impairment loss of $0.1 million upon disposal of the investment and its related carrying value.

Fair Value

Fair Value	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value	Fair Value The following table presents the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2019 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 15,088 $ — $ — $ 15,088 Investments: Commercial paper — 6,032 — 6,032 Corporate securities — 19,323 — 19,323 Asset-backed securities — 660 — 660 Certificate of deposits — 10,118 — 10,118 Total $ 15,088 $ 36,133 $ — $ 51,221 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,854 $ — $ — $ 37,854 Total $ 37,854 $ — $ — $ 37,854 The following table provides a summary of changes in the estimated fair value of the Company’s Level 3 assets measured on a non-recurring basis (in thousands): Balance at December 31, 2018 $ — Initial investment in DogHero 5,000 Balance at December 31, 2019 5,000 Impairment of DogHero investment $ (2,080) Sale of DogHero investment (2,920) Balance at December 31, 2020 $ — The following table presents the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,854 $ — $ — $ 37,854 Total assets measured at fair value $ 37,854 $ — $ — $ 37,854 September 30, 2021 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,859 $ — $ — $ 37,859 Total assets measured at fair value $ 37,859 $ — $ — $ 37,859 Liabilities Earnout liabilities $ — $ — $ 266,390 $ 266,390 Derivative warrant liabilities (Public Warrants) 23,320 — — 23,320 Derivative warrant liabilities (Private Warrants) — — 10,974 10,974 Total liabilities measured at fair value $ 23,320 $ — $ 277,364 $ 300,684 The following table provides a reconciliation of the beginning and ending balances for the level 3 financial liabilities measured at fair value using significant unobservable inputs (in thousands): Earnout Private Warrant Balance at December 31, 2020 $ — $ — Additions during the period 228,082 7,677 Change in fair value 71,318 3,297 Reclassification of earnout liability upon Triggering Events (33,010) — Balance at September 30, 2021 $ 266,390 $ 10,974 Valuation of Earnout Liabilities Upon the closing of the Merger, the Earnout Shares were accounted for as a liability because the triggering events that determine the number of shares to be earned included events that were not indexed to the common stock of the Company, with the change fair value recognized in Change in fair value of earnout liabilities in the condensed consolidated statement of operations. The estimated fair value of the Earnout Shares was determined using a Monte Carlo simulation valuation model using the following assumptions at each valuation date: July 30, September 29, 2021 September 30, 2021 Stock price $ 10.99 $ 13.59 $ 13.59 Risk-free interest rate 1.00 % 1.29 % 1.29 % Expected term (in years) 7.0 6.8 6.8 Expected volatility 57.20 % 56.50 % 56.50 % Dividend yield — % — % — % Current stock price : The stock price was based on the closing price as of the valuation date. Risk-free interest rate : The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of issuance for zero-coupon U.S. Treasury notes with maturities corresponding to the expected seven-year term of the earnout period. Expected term : The expected term is the seven-year term of the earnout period. Expected volatility : The volatility rate was determined using an average of historical volatilities of selected industry peers deemed to be comparable to the Company’s business corresponding to the expected seven-year term of the awards. Expected dividend yield : The expected dividend yield is zero as the Company currently has no history or expectation of declaring dividends in the foreseeable future. Triggering Event I and Triggering Event II occurred on September 29, 2021 resulting in the vesting of 1,969,302 Sponsor Earnout Shares on September 29, 2021 and 17,540,964 Rover Earnout Shares being subsequently issued on October 6, 2021. The estimated fair value of the earnout liability related to the Sponsor Earnout Shares was remeasured to $33.0 million on September 29, 2021, which included: (i) $26.7 million related to the Sponsor Earnout Shares that vested upon the occurrence of Triggering Event I and Triggering Event II associated with the $12.00 and $14.00 volume-weighted Class A common stock average price (“VWAP”) per share thresholds as of September 29, 2021, and was recorded to additional paid-in capital on September 29, 2021 as such shares were issued and outstanding and thus the obligation was considered settled; and (ii) $6.3 million related to the estimated fair value of the remaining 492,325 Sponsor Earnout Shares subject to vesting upon the occurrence of the Triggering Event III associated with the $16.00 VWAP per share threshold based on a Monte Carlo simulation valuation model as of September 29, 2021. On September 29, 2021, the fair value of the remaining unvested Sponsor Earnout Shares was reclassified to equity because the Sponsor Earnout Shares became an instrument contingently issuable upon the occurrence of a triggering event into a fixed number of Class A common shares that is not based on an observable market price or index other than the Company’s own common stock price. The estimated fair value of the earnout liability related to the Rover Earnout Shares was remeasured to $266.4 million on September 30, 2021, which included: (i) $238.4 million related to the Rover Earnout Shares issuable upon the occurrence of Triggering Event I and Triggering Event II associated with the $12.00 and $14.00 VWAP per share thresholds as of September 30, 2021; and (ii) $28.0 million related to the estimated fair value of the remaining 2,192,687 Rover Earnout Shares issuable upon the occurrence of the Triggering Event III associated with the $16.00 VWAP per share threshold based on a Monte Carlo simulation valuation model as of September 30, 2021. The change in fair value of the earnout liability resulted in a loss of $71.3 million recognized in the condensed consolidated statement of operations for the three and nine months ended September 30, 2021. The 17,540,964 Rover Earnout Shares that vested upon the occurrence of Triggering Event I and Triggering Event II on September 29, 2021 will be recorded at fair value until issued on October 6, 2021, at which time the then current fair value will be reclassified to additional paid in capital. Valuation of Private Warrant Derivative Liability The Private Warrants were initially recorded as a liability on the Closing Date, at a fair value of $7.7 million and were remeasured to fair value as of September 30, 2021, resulting in a loss of $3.3 million for the three and nine months ended September 30, 2021, classified within Change in fair value of derivative warrant liabilities, in the condensed consolidated statements of operations. The estimated fair value of the Private Warrants was determined using a Monte Carlo simulation valuation model using the following assumptions at each valuation date: July 30, September 30, 2021 Stock price $ 10.99 $ 13.59 Risk-free interest rate 0.69 % 0.94 % Expected term (in years) 5.0 4.8 Expected volatility 31.50 % 36.50 % Dividend yield — % — % Current stock price : The stock price was based on the closing price as of the valuation date. Risk-free interest rate : The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of issuance for zero-coupon U.S. Treasury notes with maturities corresponding to the expected with the term of the warrant expiration. Expected term : The expected term represents the period that the warrants are expected to be outstanding and is determined based on maturity of the warrants. Expected volatility : The volatility rate was determined using the implied volatility of the Public Warrants to estimate the volatility for the Private Warrants. Expected dividend yield : The expected dividend yield is zero as the Company currently has no history or expectation of declaring dividends in the foreseeable future.

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Components	Balance Sheet Components Property and Equipment, net The following table presents the detail of property and equipment, net as follows (in thousands): December 31, 2019 2020 Computers $ 1,534 $ 1,346 Furniture and fixtures 3,913 3,906 Leasehold improvements 13,136 13,660 Internal-use software 23,753 20,850 Total property and equipment 42,336 39,762 Less: Accumulated depreciation and amortization (11,345) (14,839) Total property and equipment, net $ 30,991 $ 24,923 Depreciation of property and equipment was $0.6 million, $0.6 million and $3.7 million for the years ended December 31, 2018, 2019 and 2020, respectively, and was recorded to depreciation and amortization in the consolidated statements of operations. Internal-use software amortization was $2.5 million, $5.2 million and $7.2 million for the years ended December 31, 2018, 2019 and 2020, respectively and was recorded to cost of revenue (exclusive of depreciation and amortization shown separately) in the consolidated statements of operations. In December 2019, the Company moved into its new headquarters in Seattle, Washington. Through December 31, 2020, the Company added leasehold improvements of $12.1 million and furniture and fixtures of $2.7 million in connection with the new leased space. In April 2020, the Company accelerated the amortization of $2.6 million in internal-use software related to the Rover Now service, which was discontinued and is recorded in cost of revenue (exclusive of depreciation and amortization shown separately) in the consolidated statements of operations. Accrued Expenses and Other Current Liabilities The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, 2019 2020 Accrued merchant fees $ 778 $ 172 Income and other tax liabilities 711 185 Accrued legal expenses and open claims 656 382 Lease incentive, current 453 491 Coupon liabilities 352 226 Accrued interest — 259 Accrued professional services 213 872 Series G preferred stock holdback liability 320 — Other current liabilities 1,180 160 Total accrued expenses and other current liabilities $ 4,663 $ 2,747 Property and Equipment, net The following table presents the detail of property and equipment, net as follows (in thousands): December 31, September 30, Computers $ 1,346 $ 1,632 Furniture and fixtures 3,906 3,857 Leasehold improvements 13,660 13,663 Internal-use software 20,850 22,081 Total property and equipment 39,762 41,233 Less: Accumulated depreciation and amortization (14,839) (19,281) Total property and equipment, net $ 24,923 $ 21,952 Depreciation and amortization of property and equipment was $1.0 million and $2.9 million for the three and nine months ended September 30, 2021, respectively, and $0.9 million and $2.7 million for the three and nine months ended September 30, 2020, respectively. Depreciation and amortization of property and equipment was recorded to depreciation and amortization in the condensed consolidated statements of operations. Internal-use software amortization was $1.7 million and $5.2 million for the three and nine months ended September 30, 2021, respectively, and $1.8 million and $5.6 million for the three and nine months ended September 30, 2020, respectively. Internal-use software amortization was recorded to cost of revenue (exclusive of depreciation and amortization shown separately) in the condensed consolidated statements of operations. In April 2020, the Company accelerated the amortization of $2.6 million in internal-use software related to the Rover Now service which was discontinued and is recorded in cost of revenue (exclusive of depreciation and amortization shown separately) in the condensed consolidated statements of operations. Accrued Expenses and Other Current Liabilities The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, September 30, Accrued merchant fees $ 172 $ 8 Income and other tax liabilities 185 1,012 Accrued legal expenses and open claims 382 1,017 Lease incentive, current 491 — Accrued interest 259 14 Accrued professional services 872 540 Other current liabilities 386 238 Total accrued expenses and other current liabilities $ 2,747 $ 2,829

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill The following table summarizes the changes in the carrying amount of goodwill (in thousands): Balance at December 31, 2018 $ 34,811 Measurement period adjustment – DogBuddy (see Note 3—Business Combinations) (1,652) Balance at December 31, 2019 $ 33,159 There was no change in the carrying amount of goodwill during the year ended December 31, 2020. Intangible Assets The gross book value and accumulated amortization of intangible assets were as follows (in thousands): December 31, 2019 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (6,364) $ 9,926 Technologies 10,100 (8,525) 1,575 Pet service provider relationships 2,000 (778) 1,222 Tradenames 950 (522) 428 Total $ 29,340 $ (16,189) $ 13,151 December 31, 2020 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (9,117) $ 7,173 Pet service provider relationships 2,000 (1,444) 556 Tradenames 950 (712) 238 Total $ 19,240 $ (11,273) $ 7,967 The weighted average amortization period remaining as of December 31, 2020 for each class of intangible assets were as follows (in years): Pet parent relationships 4.3 Pet service provider relationships 0.8 Tradenames 1.3 Amortization expense related to acquired intangible assets for the years ended December 31, 2018, 2019 and 2020 was $6.6 million, $7.7 million and $5.2 million, respectively. The Company did not recognize any intangible asset impairment losses for any of the periods presented. Based on amounts recorded at December 31, 2020 the Company estimates intangible asset amortization expense in each of the years ending December 31 as follows (in thousands): 2021 $ 3,499 2022 1,347 2023 814 2024 814 2025 814 Thereafter 679 Total $ 7,967 Goodwill The Company tests goodwill for impairment on an annual basis or sooner, if deemed necessary. No impairment of goodwill was recognized during any of the periods presented. Intangible Assets The gross book value and accumulated amortization of intangible assets were as follows (in thousands): December 31, 2020 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (9,117) $ 7,173 Pet service provider relationships 2,000 (1,444) 556 Tradenames 950 (712) 238 Total $ 19,240 $ (11,273) $ 7,967 September 30, 2021 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 (11,181) $ 5,109 Pet service provider relationships 2,000 (1,944) 56 Tradenames 950 (855) 95 Total $ 19,240 $ (13,980) $ 5,260 The weighted average amortization period remaining as of September 30, 2021 for each class of intangible assets were as follows (in years): Pet parent relationships 4.2 Pet service provider relationships 0.1 Tradenames 0.5 Amortization expense related to acquired intangible assets for the three and nine months ended September 30, 2021 was $0.9 million and $2.7 million, respectively, and $1.2 million and $4.2 million for the three and nine months ended September 30, 2020, respectively. The Company did not recognize any intangible asset impairment losses for any of the periods presented. Based on amounts recorded at September 30, 2021, the Company estimates intangible asset amortization expense in each of the years ending December 31 as follows (in thousands): Remainder of 2021 $ 792 2022 1,347 2023 814 2024 814 2025 814 Thereafter 679 Total $ 5,260

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt In May 2018, the Company entered into a $30.0 million credit facility agreement with a lender consisting of a $15.0 million variable rate revolving line of credit and a $15.0 million variable rate growth capital advance, which originally matured in May 2020 and May 2022, respectively. In August 2019, the Company amended the credit facility with the lender which extended the period in which the Company may make borrowings under the growth capital advance component and extended the maturity dates by one year to May 2021 for the revolving line of credit and to May 2023 for the variable rate growth capital advance. Concurrently, the Company entered into a subordinated credit facility agreement with a lender consisting of a $30.0 million variable rate term loan advance, which matures in August 2022. In March 2020, the Company borrowed $11.4 million and $15.0 million under the variable rate revolving line of credit and variable rate growth capital advance components, respectively, of the credit facility, and $30.0 million under the subordinated credit facility. In April 2020, the Company was approved for and received a $8.1 million loan from the Small Business Administration’s Paycheck Protection Program. Revolving Line of Credit The Company renegotiated the credit facility during August 2020 to extend the maturity of the revolving line of credit to May 2022. Subject to the terms and conditions of the credit facility, the lender agreed to make revolving loans to the Company in an amount not to exceed $15.0 million during the term of the agreement. Interest accrues at the greater of (1) 4.50% and (2) the Prime Rate plus a margin of 0.50% per year (4.50% at December 31, 2020), unless certain milestones are achieved then interest accrues at the greater of (1) 4.00% and (2) the Prime Rate. Interest is payable monthly. In connection with securing the revolving loan, the Company incurred $22,500 in costs related to originating the debt which were capitalized as debt issuance costs. The costs are recorded as current and long-term assets in the consolidated balance sheets and are amortized into interest expense over the term of the revolving loan. The Company is required to pay an unused credit facility fee to the lender each quarter in an amount equal to 0.30% per year times the average unused portion of the revolving line. The Company borrowed and repaid $11.4 million on the revolving loan during the year ended December 31, 2020 and issued a $3.5 million letter of credit for the security deposit on its Seattle headquarters office space, which reduced the amount available under the revolving line of credit. The Company had $11.4 million available to borrow under the revolving line of credit at December 31, 2020. Growth Capital Advance The Company renegotiated the credit facility during August 2020 to amend the growth capital advance component, including extending the maturity to June 2024. Subject to the terms and conditions of the credit facility, the lender agreed to make advances to the Company in three tranches not to exceed $5.0 million under each tranche, up to the total amount of $15.0 million during the draw period, which was available until June 30, 2021. Advance requests must be in an amount equal to or greater than $1.0 million. After principal repayments, no growth capital advance may be reborrowed. The growth capital advances is interest only through June 2021 and is payable monthly. Beginning in July 2021 and continuing through the maturity date, principal and interest shall be payable in 36 consecutive equal monthly installments. Interest shall accrue at the greater of (1) 5.00% and (2) the Prime Rate plus a margin of 1.00% per year (5.00% at December 31, 2020), unless certain milestones are achieved then the margin is the greater of (1) 4.50% and (2) the Prime Rate plus a margin of 0.50% per year. In connection with securing the growth capital advance, the Company incurred $25,000 in costs related to originating the debt which were capitalized as debt issuance costs. The costs are recorded as current and long-term assets in the consolidated balance sheets and are amortized into interest expense over the term of the growth capital advance. During 2020, the Company had drawn on the $15.0 million growth capital advance and repaid the outstanding balance. At December 31, 2020, the Company had $15.0 million available to borrow. For the year ended December 31, 2020, the Company recognized a loss of $353,000 related to the early repayment of the growth capital advance, which is recorded in other income (expense), net in the consolidated statements of operations and included in amortization of debt issuance costs in the consolidated statements of cash flows. Subordinated Credit Facility The subordinated credit facility is a term loan advance. Subject to the terms and conditions of the subordinated credit facility, the lender agreed to make advances to the Company to the amount of $30.0 million during the draw period, which was available until June 30, 2020. Advance requests must be in an amount equal to or greater than $5.0 million. After principal repayments, no term loan advance may be reborrowed. The term loan advance is interest only on a monthly basis. Outstanding principal and accrued interest are due at the maturity date. Interest shall accrue at the Prime Rate plus a margin of 4.25% per year (7.50% at December 31, 2020). In connection with securing the term loan advance, the Company incurred $269,000 in costs related to originating the debt which were capitalized as debt issuance costs. The costs are recorded as a debt discount and are amortized to interest expense over the term of the term loan advance. At December 31, 2020, the Company has drawn the full $30.0 million term loan advance and no longer has the ability to make any future draws. The Company has collateralized the credit facility and the subordinated credit facility with substantially all of its tangible and intangible assets. The credit facility includes several affirmative and negative covenants, as well as financial covenants. Financial covenants include minimum liquidity and minimum net revenue amounts and are applicable if the Company’s overall liquidity, as defined by the credit facility, is less than or equal to $75.0 million at the end of a reporting period. If the Company defaulted under the terms of the credit facility, it would not be permitted to draw additional funds on the revolving line of credit and the lenders could accelerate the Company’s obligation to pay all outstanding amounts. The Company is in compliance with all of its financial covenants as of December 31, 2020. In conjunction with the credit facility and the subordinated credit facility, the Company issued warrants to the lenders to purchase the Company’s common stock (see Note 13—Common Stock). Small Business Administration’s Paycheck Protection Program In April 2020, the Company entered into the Paycheck Protection Program (“PPP”) Promissory Note and Agreement with a lender (the “PPP Loan”), pursuant to which it incurred $8.1 million aggregate principal amount of term borrowings. The PPP Loan was made under, and was subject to the terms and conditions of, the PPP which was established under the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) and is administered by the U.S. Small Business Administration. The term of the PPP Loan is two years with a maturity date of April 2022 and accrues interest at a rate of 1.00% per year. Interest is payable monthly. Payments of principal and interest on the PPP Loan are deferred until August 2021. The PPP Loan is eligible for forgiveness if the proceeds are used for qualified purposes within a specified period, however Rover expects to repay principal and accrued interest on the PPP Loan. At December 31, 2020, $8.1 million aggregate principal amount of borrowings was outstanding under the PPP loan. Future minimum payments of principal on the Company’s outstanding debt borrowings were as follows for the years ending December 31 (in thousands): Year Ending December 31 Amounts 2021 4,505 2022 33,619 2023 — 2024 — 2025 — Total principal amount 38,124 Unamortized discount (598) Carrying value of debt 37,526 In March 2020, the Company borrowed $11.4 million and $15.0 million under the variable rate revolving line of credit and variable rate growth capital advance components, respectively, of the credit facility, and $30.0 million under the subordinated credit facility. In April 2020, the Company was approved for and received a $8.1 million loan from the Small Business Administration’s Paycheck Protection Program (“PPP”). In August 2020, the Company repaid the outstanding balance of the revolving line of credit and the growth capital advance. Upon closing of the Merger, the Company repaid in full the subordinated credit facility of $30.0 million and the PPP loan of $8.1 million. Additionally, in accordance with the subordinated credit facility, the Company made a final termination payment of $0.9 million and accelerated $0.4 million of unamortized debt issuance costs at the termination of the subordinated credit facility. As of September 30, 2021, the Company had no debt outstanding and terminated its revolving line of credit. Revolving Line of Credit The Company renegotiated the credit facility during August 2020 to extend the maturity of the revolving line of credit to May 2022. Subject to the terms and conditions of the credit facility, the lender agreed to make revolving loans to the Company in an amount not to exceed $15.0 million during the term of the agreement. Interest accrued at the greater of (1) 4.50% and (2) the Prime Rate plus a margin of 0.50% per year (4.50% at September 30, 2021), unless certain milestones were achieved then interest accrued at the greater of (1) 4.00% and (2) the Prime Rate. Interest was payable monthly. The Company was required to pay an unused credit facility fee to the lender each quarter in an amount equal to 0.30% per year times the average unused portion of the revolving line. The Company borrowed and repaid $11.4 million on the revolving loan during the year ended December 31, 2020 and issued a $3.5 million letter of credit for the security deposit on its Seattle headquarters and Spokane office space, which reduced the amount available under the revolving line of credit. At September 30, 2021, the Company closed its revolving line of credit and retained an unsecured $3.5 million letter of credit for the security deposit on its Seattle headquarters and Spokane office space. Growth Capital Advance The Company renegotiated the credit facility during August 2020 to amend the growth capital advance component, including extending the maturity to June 2024. Subject to the terms and conditions of the credit facility, the lender agreed to make advances to the Company in three tranches not to exceed $5.0 million under each tranche, up to the total amount of $15.0 million during the draw period, which was available until June 30, 2021. During 2020, the Company drew on the $15.0 million growth capital advance and repaid the outstanding balance. At September 30, 2021, no amounts were outstanding, and the Company can no longer borrow under the growth capital advance component of the credit facility. Subordinated Credit Facility The subordinated credit facility was a term loan advance. Subject to the terms and conditions of the subordinated credit facility, the lender agreed to make advances to the Company to the amount of $30.0 million during the draw period, which was available until June 30, 2020. After principal repayments, no term loan advance were able to be reborrowed. The term loan advance was interest only on a monthly basis. Outstanding principal and accrued interest were due at the maturity date. Interest accrued at the Prime Rate plus a margin of 4.25% per year (7.50% at September 30, 2021). In connection with securing the term loan advance, the Company incurred $269,000 in costs related to originating the debt which were initially capitalized as debt issuance costs. Once the term loan advance of $30.0 million was drawn down in March 2020, the costs were recorded as a debt discount and amortized to interest expense over the term of the term loan advance. Upon closing of the Merger, the Company repaid the full $30.0 million term loan advance, and accrued interest of $0.2 million. As of September 30, 2021, the Company no longer has the ability to make any future draws. The Company had collateralized the credit facility and the subordinated credit facility with substantially all of its tangible and intangible assets. The credit facility included several affirmative and negative covenants, as well as financial covenants. Financial covenants included minimum liquidity and minimum net revenue amounts and were applicable if the Company’s overall liquidity, as renegotiated in March 2021, was less than or equal to $65.0 million at the end of a reporting period. If the Company defaulted under the terms of the credit facility, it would not be permitted to draw additional funds on the revolving line of credit and the lenders could accelerate the Company’s obligation to pay all outstanding amounts. The Company was in compliance with all of its financial covenants as of the date of its full repayment of the term loan advance upon the Closing of the Merger. In conjunction with the credit facility and the subordinated credit facility, the Company issued warrants to the lenders to purchase the Company’s common stock. Small Business Administration’s Paycheck Protection Program In April 2020, the Company entered into the PPP Promissory Note and Agreement, pursuant to which it incurred $8.1 million aggregate principal amount of term borrowings. The PPP loan was made under, and was subject to the terms and conditions of, the PPP which was established under the Coronavirus Aid, Relief, and Economic Security Act and was administered by the U.S. Small Business Administration. The term of the PPP loan was two years with a maturity date of April 2022 and accrued interest at a rate of 1.00% per year. Interest was payable monthly. Payments of principal and interest on the PPP loan were deferred until August 2021. The PPP loan was eligible for forgiveness if the proceeds were used for qualified purposes within a specified period. Upon the Closing of the Merger, the Company repaid the PPP loan of $8.1 million and accrued interest of $0.1 million.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases The Company entered into noncancelable operating lease agreements primarily covering certain of its offices in Seattle and Spokane, Washington and Barcelona, Spain, with the lease periods expiring between 2019 and 2030. In September 2018, the Company entered into a non-cancellable sublease agreement for a portion of one of its leased facilities that commenced on November 1, 2018. In February 2020, the Company amended the sublease to extend the term for an additional two years. Under the term of the amended sublease agreement, the Company will receive $1.4 million in base lease payments plus reimbursement of certain operating expenses over the term of the sublease, which ends in October 2022. During the years ended December 31, 2018, 2019 and 2020, the Company recognized $0.1 million, $0.7 million and $0.7 million, respectively, of sublease income under this agreement. In June 2019, the Company exited a leased property in Spokane, Washington. The Company entered into negotiation with the landlord to determine a termination fee during December 2019 after unsuccessfully being able to sublease the property. At the time of exit, the Company recognized a cease-use liability of $361,000. At December 31, 2019, a cease-use liability of $297,000 remained and is recorded in accrued expenses and other current liabilities in the consolidated balance sheets. The final termination fee was paid to the landlord in March 2020. The minimum future lease obligations in each of the years ending December 31 are as follows (in thousands): Year Ending December 31 Amounts 2021 $ 4,356 2022 4,303 2023 4,433 2024 4,563 2025 4,693 Thereafter 18,209 Total $ 40,557 Facilities rent expense under these operating leases was $2.1 million, $4.0 million and $3.6 million for the years ended December 31, 2018, 2019 and 2020, respectively. The Company is responsible for paying its proportionate share of the actual operating expenses and real estate taxes under these lease agreements. Guarantees and Indemnification In the ordinary course of business to facilitate sales of its services, the Company has entered into agreements with, among others, suppliers, and partners that include guarantees or indemnity provisions. The Company also enters into indemnification agreements with its officers and directors, and the Company’s certificate of incorporation and bylaws include similar indemnification obligations to its officers and directors. To date, there have been no claims under any indemnification provisions, therefore there is no accrual of such amounts for any of the periods presented. The Company is unable to determine the maximum potential impact of these indemnifications on the consolidated financial statements and maintains director and officer insurance coverage that would generally enable it to recover a portion of any future amounts paid. Litigation and Other From time to time, the Company may be a party to litigation and subject to claims incurred in the ordinary course of business, including personal injury and indemnification claims, intellectual property claims, labor and employment claims, threatened claims, breach of contract claims, and other matters. The Company accrues a liability when management believes information available prior to the issuance of the consolidated financial statements indicates it is probable a loss has been incurred as of the date of the consolidated financial statements and the amount of loss can be reasonably estimated. The Company adjusts its accruals to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular case. Legal costs are expensed as incurred. Although the results of litigation and claims are inherently unpredictable, management concluded that there was not a reasonable possibility that it had incurred a material loss during the periods presented related to such loss contingencies. Therefore, the Company has not recorded a reserve for any contingencies. Given the inherent uncertainties of litigation, the ultimate outcome of the ongoing matters cannot be predicted with certainty. While litigation is inherently unpredictable, the Company believes it has valid defenses with respect to the legal matters pending against it. Nevertheless, the consolidated financial statements could be materially adversely affected in a particular period by the resolution of one or more of these contingencies. Liabilities established to provide for contingencies are adjusted as further information develops, circumstances change, or contingencies are resolved; and such changes are recorded in the accompanying consolidated statements of operations during the period of the change and reflected in accrued and other current liabilities on the accompanying consolidated balance sheets. In addition, the Company may also find itself at greater risk to outside party claims or regulatory actions as it increases and continues its operations in jurisdictions where the laws with respect to the potential liability of online marketplaces or the employment classification of service providers who use online marketplaces are uncertain, unfavorable or unclear. Additionally, from time to time, the Company may become subject to audit by taxing authorities or subject to other forms of inspection or audit. Due to the uncertainties inherent in the final outcome of such matters, the Company can give no assurance that it will prevail in such matters which could have an adverse effect on the Company’s business. As of December 31, 2019 and 2020, the Company was not aware of any currently pending legal matters or claims, individually or in the aggregate, that are expected to have a material adverse impact on its consolidated financial statements. Leases The Company leases certain office space in Seattle and Spokane, Washington and Barcelona, Spain with the lease terms ranging from 21 to 137 months. These leases require monthly lease payments that may be subject to annual increases throughout the lease term. Certain of these leases also include renewal options at the election of the Company to renew or extend the lease for an additional 1 to 7 years. These renewal options have not been considered in the determination of the ROU assets and lease liabilities associated with these leases as the Company has determined it is not reasonably certain it will exercise such options. In September 2018, the Company entered into a non-cancellable sublease agreement for a portion of one of its leased facilities that commenced on November 1, 2018. In February 2020, the Company amended the sublease to extend the term for an additional two years. Under the terms of the amended sublease agreement, the Company will receive an additional $1.4 million in base lease payments plus reimbursement of certain operating expenses over the term of the sublease, which ends in October 2022. In April 2021, the Company entered into a non-cancellable sublease agreement for a portion of one of its leased facilities that commenced on September 1, 2021. Under the terms of the sublease agreement, the Company will receive $1.7 million in base lease payments plus reimbursement of certain operating expenses over the term of the sublease, which ends in August 2024. The subtenant has the option to renew the sublease for one The components of lease cost were as follows (in thousands): Three Months Ended Nine Months Ended Operating lease cost $ 1,046 $ 3,011 Short-term lease cost 19 138 Sublease income (304) (649) Total lease cost $ 761 $ 2,500 Other information related to leases was as follows (in thousands): Nine Months Ended Cash paid for operating lease liabilities $ 3,159 Lease term and discount rate were as follows: As of September 30, 2021 Weighted-average discount rate 7.12 % Weighted-average remaining lease term (years) 7.88 Maturities of lease liabilities were as follows as of September 30, 2021 (in thousands): Year Ending December 31 Amounts Remainder of 2021 $ 1,156 2022 4,669 2023 4,700 2024 4,563 2025 4,693 Thereafter 18,209 Total lease payments 37,990 Less: imputed interest (9,331) Present value of lease liabilities 28,659 Less: current portion of lease liabilities (2,726) Total lease liabilities, noncurrent $ 25,933 Under ASC Topic 840, Leases , contractual commitments related to operating leases were as follows as of December 31, 2020 (in thousands): Year Ending December 31 Amounts 2021 $ 4,356 2022 4,303 2023 4,433 2024 4,563 2025 4,693 Thereafter 18,209 Total $ 40,557 Net rent expense was $1.0 million and $2.8 million for the three and nine months ended September 30, 2020, respectively. Net rent expense includes sublease income of $0.2 million and $0.6 million for the three and nine months ended September 30, 2020, respectively. Guarantees and Indemnification In the ordinary course of business to facilitate sales of its services, the Company has entered into agreements with, among others, suppliers, and partners that include guarantees or indemnity provisions. The Company also enters into indemnification agreements with its officers and directors, and the Company’s certificate of incorporation and bylaws include similar indemnification obligations to its officers and directors. To date, there have been no claims under any indemnification provisions, therefore there is no accrual of such amounts for any of the periods presented. The Company is unable to determine the maximum potential impact of these indemnifications on the condensed consolidated financial statements and maintains director and officer insurance coverage that would generally enable it to recover a portion of any future amounts paid. Litigation and Other From time to time, the Company may be a party to litigation and subject to claims incurred in the ordinary course of business, including personal injury and indemnification claims, intellectual property claims, labor and employment claims, threatened claims, breach of contract claims, and other matters. The Company accrues a liability when management believes information available prior to the issuance of the condensed consolidated financial statements indicates it is probable a loss has been incurred as of the date of the condensed consolidated financial statements and the amount of loss can be reasonably estimated. The Company adjusts its accruals to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular case. Legal costs are expensed as incurred. Although the results of litigation and claims are inherently unpredictable, management concluded that there was not a reasonable possibility that it had incurred a material loss during the periods presented related to such loss contingencies. Therefore, the Company has not recorded a reserve for any contingencies. Given the inherent uncertainties of litigation, the ultimate outcome of the ongoing matters cannot be predicted with certainty. While litigation is inherently unpredictable, the Company believes it has valid defenses with respect to the legal matters pending against it. Nevertheless, the condensed consolidated financial statements could be materially adversely affected in a particular period by the resolution of one or more of these contingencies. Liabilities established to provide for contingencies are adjusted as further information develops, circumstances change, or contingencies are resolved; and such changes are recorded in the accompanying condensed consolidated statements of operations during the period of the change and reflected in accrued and other current liabilities on the accompanying condensed consolidated balance sheets. In addition, the Company may also find itself at greater risk to outside party claims or regulatory actions as it increases and continues its operations in jurisdictions where the laws with respect to the potential liability of online marketplaces or the employment classification of service providers who use online marketplaces are uncertain, unfavorable or unclear.

Employee Benefit Plan

Employee Benefit Plan	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Employee Benefit Plan	Employee Benefit PlanThe Company has established a 401(k) tax-deferred savings plan covering all employees who satisfy certain eligibility requirements. The 401(k) plan allows each participant to defer a percentage of their eligible compensation subject to applicable annual limits pursuant to the limits established by the Internal Revenue Service (“IRS”). The Company may, at its discretion, make contributions in the form of matching contributions, subject to limitations imposed by the IRS. As of December 31, 2020, the Company has not made any matching contributions.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders' Equity	Common Stock Common Stock As of December 31, 2019 and 2020, the Company was authorized to issue 144.3 million shares of common stock with a $0.0001 per share par value. Each holder of a share of common stock is entitled to one vote for each share held at all meetings of stockholders and is entitled to receive dividends whenever funds are legally available and when declared by the board of directors subject to the preferential rights of holders of all classes of stock outstanding. The total common stock outstanding as of December 31, 2019 and 2020 was 29.6 million and 30.4 million shares, respectively. The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows (in thousands): December 31 2019 2020 Conversion of redeemable convertible preferred stock 90,805 90,814 Common stock warrants outstanding 790 1,118 Stock options issued and outstanding 24,911 24,700 Shares available for future option grants 4,094 5,199 Total 120,600 121,831 Common Stock Warrants On March 29, 2017, in connection with the acquisition of DogVacay, Inc. (“DogVacay”), the Company issued warrants to investors to purchase up to 26,000 shares of common stock at an exercise price of $3.23 to $3.41 per share. The warrants were valued at the date of acquisition at $20,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $1.52, a risk-free interest rate of 2.38%, a contractual term of 10 years, a dividend rate of 0% and a volatility of 54.9% and were recorded within additional paid-in capital in stockholders’ deficit. At December 31, 2020, the warrants were outstanding and due to expire August 2026 and March 2027. On May 23, 2018, in conjunction with the credit facility described in Note 9—Debt, the Company issued to the lender a warrant to purchase up to 26,940 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $50,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.11, a risk-free interest rate of 2.99%, a contractual term of 10 years, a dividend rate of 0%, and a volatility of 45.0% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was recorded as deferred financing costs and was amortized to interest expense over the remaining term of the amended credit facility. At December 31, 2020, the warrant was outstanding and due to expire on May 23, 2028. On August 9, 2018, in conjunction with a consulting agreement, the Company issued to a consultant a warrant to purchase up to 487,816 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $642,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.11, a risk-free interest rate of 2.78%, a contractual term of 4.88 years, a dividend rate of 0% and a volatility of 45.0% and is recognized ratably within general and administrative expense over the service period of the related consulting agreement. At December 31, 2020, the warrant was outstanding and due to expire and no longer be exercisable on the earlier of: (1) June 1, 2023 and (2) the closing of a transaction that constitutes a qualified acquisition, reorganization, merger or consideration, a sale of substantially all the assets of the Company, or any liquidation event. On August 5, 2019, in conjunction with the subordinated credit facility described in Note 9—Debt, the Company issued warrants to two lenders to purchase up to 50,984 shares of common stock each at an exercise price of $3.52 per share. The warrants were valued at the date of issuance at $207,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.52, a risk-free interest rate of 1.74%, a contractual term of 10 years, a dividend rate of 0%, and a volatility of 46.3% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was initially recorded as deferred financing costs and will be reclassified to debt discount once amounts are borrowed under the agreement. The deferred financing costs and debt discount will be amortized to interest expense over the remaining term of the subordinated credit facility. At December 31, 2020, the warrants were outstanding and due to expire on August 5, 2029. On August 5, 2019, in conjunction with the extension of the maturity date of the credit facility described in Note 9—Debt, the Company issued to the lender a warrant to purchase up to 13,470 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $27,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.52, a risk-free interest rate of 1.74%, a contractual term of 8.75 years, a dividend rate of 0%, and a volatility of 46.3% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was initially recorded as deferred financing costs and the portion related to the term debt will be reclassified to debt discount once amounts are borrowed under the agreement. The deferred financing costs and debt discount will be amortized to interest expense over the remaining term of the credit facility. At December 31, 2020 the warrant was outstanding and due to expire on May 23, 2028. On March 20, 2020, in conjunction with the borrowing of $30.0 million under the subordinated credit facility described in Note 9—Debt, the Company issued warrants to two lenders to purchase up to 94,686 shares of common stock each at an exercise price of $3.52 per share. The warrants were valued on the date of issuance at $189,000 using the Black-Scholes option pricing model using an estimated per share fair value of $3.53, a risk-free interest rate of 0.90%, a contractual term of 9.4 years, a dividend rate of 0%, and a volatility of 49.0% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was recorded as debt discount and will be amortized to interest expense over the remaining term of the subordinated credit facility. At December 31, 2020, the warrants were outstanding and due to expire on August 5, 2029. Common Stock On August 2, 2021, the Company’s Class A common stock and Public Warrants began trading on the Nasdaq Global Select Market under the ticker symbols “ROVR” and “ROVW,” respectively. Pursuant to the Company’s certificate of incorporation, the Company is authorized to issue 990,000,000 shares of Class A common stock with a par value of $0.0001 per share. As of September 30, 2021, the Company had 157.6 million shares of Class A common stock issued and outstanding. Prior to the Merger, Legacy Rover had outstanding shares of Series A, Series B, Series C, Series D, Series D-1, Series E, Series F, and Series G redeemable convertible preferred stock. Upon the Closing, each share of Legacy Rover redeemable convertible preferred stock was converted to one share of Legacy Rover common stock. Holders of the outstanding Legacy Rover common stock received shares of the Company’s Class A common stock in an amount determined by application of the Exchange Ratio, as discussed in Note 3—Reverse Recapitalization. The Company had reserved shares of Class A common stock for issuance, on an as-converted basis, as follows (in thousands): December 31, September 30, Conversion of redeemable convertible preferred stock 90,814 — Common stock warrants outstanding 1,118 — Private Warrants — 2,574 Public Warrants — 5,500 Rover Earnout Shares — 19,734 Sponsor Earnout Shares — 492 Stock options issued and outstanding 24,700 19,955 Shares available for future equity grants 5,199 17,258 Total 121,831 65,513 Preferred Stock Pursuant to the Company’s certificate of incorporation, the Company is authorized to issue 10,000,000 shares of preferred stock having a par value of $0.0001 per share. The Company’s board of directors has the authority to issue preferred stock and to determine the rights, preferences, privileges, and restrictions, including voting rights, of those shares. As of September 30, 2021, no shares of preferred stock were issued and outstanding. The Company had outstanding redeemable convertible preferred stock as of December 31, 2020 as follows (in thousands, except per share amounts): Shares Authorized Shares Issued and Outstanding Issuance Price Per Share Net Carrying Value Liquidation Preference Series A 8,710 9,040 $0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802 As of September 30, 2021 all redeemable convertible preferred stock had been converted to Class A common stock of the Company. Dividend Class A common stock is entitled to dividends when and if declared by the Company’s board of directors, subject to the rights of all classes of stock outstanding having priority rights to dividends. The Company has not paid any cash dividends on common stock to date. The Company may retain future earnings, if any, for the further development and expansion of its business and has no current plans to pay cash dividends for the foreseeable future. Any future determination to pay dividends will be made at the discretion of the Company’s board of directors and will depend on, among other things, the Company’s financial condition, results of operations, capital requirements, restrictions contained in future agreements and financing instruments, business prospects and such other factors as the Company’s board of directors may deem relevant.

Common Stock

Common Stock	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Common Stock	Common Stock Common Stock As of December 31, 2019 and 2020, the Company was authorized to issue 144.3 million shares of common stock with a $0.0001 per share par value. Each holder of a share of common stock is entitled to one vote for each share held at all meetings of stockholders and is entitled to receive dividends whenever funds are legally available and when declared by the board of directors subject to the preferential rights of holders of all classes of stock outstanding. The total common stock outstanding as of December 31, 2019 and 2020 was 29.6 million and 30.4 million shares, respectively. The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows (in thousands): December 31 2019 2020 Conversion of redeemable convertible preferred stock 90,805 90,814 Common stock warrants outstanding 790 1,118 Stock options issued and outstanding 24,911 24,700 Shares available for future option grants 4,094 5,199 Total 120,600 121,831 Common Stock Warrants On March 29, 2017, in connection with the acquisition of DogVacay, Inc. (“DogVacay”), the Company issued warrants to investors to purchase up to 26,000 shares of common stock at an exercise price of $3.23 to $3.41 per share. The warrants were valued at the date of acquisition at $20,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $1.52, a risk-free interest rate of 2.38%, a contractual term of 10 years, a dividend rate of 0% and a volatility of 54.9% and were recorded within additional paid-in capital in stockholders’ deficit. At December 31, 2020, the warrants were outstanding and due to expire August 2026 and March 2027. On May 23, 2018, in conjunction with the credit facility described in Note 9—Debt, the Company issued to the lender a warrant to purchase up to 26,940 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $50,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.11, a risk-free interest rate of 2.99%, a contractual term of 10 years, a dividend rate of 0%, and a volatility of 45.0% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was recorded as deferred financing costs and was amortized to interest expense over the remaining term of the amended credit facility. At December 31, 2020, the warrant was outstanding and due to expire on May 23, 2028. On August 9, 2018, in conjunction with a consulting agreement, the Company issued to a consultant a warrant to purchase up to 487,816 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $642,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.11, a risk-free interest rate of 2.78%, a contractual term of 4.88 years, a dividend rate of 0% and a volatility of 45.0% and is recognized ratably within general and administrative expense over the service period of the related consulting agreement. At December 31, 2020, the warrant was outstanding and due to expire and no longer be exercisable on the earlier of: (1) June 1, 2023 and (2) the closing of a transaction that constitutes a qualified acquisition, reorganization, merger or consideration, a sale of substantially all the assets of the Company, or any liquidation event. On August 5, 2019, in conjunction with the subordinated credit facility described in Note 9—Debt, the Company issued warrants to two lenders to purchase up to 50,984 shares of common stock each at an exercise price of $3.52 per share. The warrants were valued at the date of issuance at $207,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.52, a risk-free interest rate of 1.74%, a contractual term of 10 years, a dividend rate of 0%, and a volatility of 46.3% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was initially recorded as deferred financing costs and will be reclassified to debt discount once amounts are borrowed under the agreement. The deferred financing costs and debt discount will be amortized to interest expense over the remaining term of the subordinated credit facility. At December 31, 2020, the warrants were outstanding and due to expire on August 5, 2029. On August 5, 2019, in conjunction with the extension of the maturity date of the credit facility described in Note 9—Debt, the Company issued to the lender a warrant to purchase up to 13,470 shares of common stock at an exercise price of $3.11 per share. The warrant was valued at the date of issuance at $27,000 using the Black-Scholes option pricing model using an estimated per share fair value of common stock of $3.52, a risk-free interest rate of 1.74%, a contractual term of 8.75 years, a dividend rate of 0%, and a volatility of 46.3% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was initially recorded as deferred financing costs and the portion related to the term debt will be reclassified to debt discount once amounts are borrowed under the agreement. The deferred financing costs and debt discount will be amortized to interest expense over the remaining term of the credit facility. At December 31, 2020 the warrant was outstanding and due to expire on May 23, 2028. On March 20, 2020, in conjunction with the borrowing of $30.0 million under the subordinated credit facility described in Note 9—Debt, the Company issued warrants to two lenders to purchase up to 94,686 shares of common stock each at an exercise price of $3.52 per share. The warrants were valued on the date of issuance at $189,000 using the Black-Scholes option pricing model using an estimated per share fair value of $3.53, a risk-free interest rate of 0.90%, a contractual term of 9.4 years, a dividend rate of 0%, and a volatility of 49.0% and were recorded within additional paid-in capital in stockholders’ deficit. The fair value of the common stock warrants was recorded as debt discount and will be amortized to interest expense over the remaining term of the subordinated credit facility. At December 31, 2020, the warrants were outstanding and due to expire on August 5, 2029. Common Stock On August 2, 2021, the Company’s Class A common stock and Public Warrants began trading on the Nasdaq Global Select Market under the ticker symbols “ROVR” and “ROVW,” respectively. Pursuant to the Company’s certificate of incorporation, the Company is authorized to issue 990,000,000 shares of Class A common stock with a par value of $0.0001 per share. As of September 30, 2021, the Company had 157.6 million shares of Class A common stock issued and outstanding. Prior to the Merger, Legacy Rover had outstanding shares of Series A, Series B, Series C, Series D, Series D-1, Series E, Series F, and Series G redeemable convertible preferred stock. Upon the Closing, each share of Legacy Rover redeemable convertible preferred stock was converted to one share of Legacy Rover common stock. Holders of the outstanding Legacy Rover common stock received shares of the Company’s Class A common stock in an amount determined by application of the Exchange Ratio, as discussed in Note 3—Reverse Recapitalization. The Company had reserved shares of Class A common stock for issuance, on an as-converted basis, as follows (in thousands): December 31, September 30, Conversion of redeemable convertible preferred stock 90,814 — Common stock warrants outstanding 1,118 — Private Warrants — 2,574 Public Warrants — 5,500 Rover Earnout Shares — 19,734 Sponsor Earnout Shares — 492 Stock options issued and outstanding 24,700 19,955 Shares available for future equity grants 5,199 17,258 Total 121,831 65,513 Preferred Stock Pursuant to the Company’s certificate of incorporation, the Company is authorized to issue 10,000,000 shares of preferred stock having a par value of $0.0001 per share. The Company’s board of directors has the authority to issue preferred stock and to determine the rights, preferences, privileges, and restrictions, including voting rights, of those shares. As of September 30, 2021, no shares of preferred stock were issued and outstanding. The Company had outstanding redeemable convertible preferred stock as of December 31, 2020 as follows (in thousands, except per share amounts): Shares Authorized Shares Issued and Outstanding Issuance Price Per Share Net Carrying Value Liquidation Preference Series A 8,710 9,040 $0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802 As of September 30, 2021 all redeemable convertible preferred stock had been converted to Class A common stock of the Company. Dividend Class A common stock is entitled to dividends when and if declared by the Company’s board of directors, subject to the rights of all classes of stock outstanding having priority rights to dividends. The Company has not paid any cash dividends on common stock to date. The Company may retain future earnings, if any, for the further development and expansion of its business and has no current plans to pay cash dividends for the foreseeable future. Any future determination to pay dividends will be made at the discretion of the Company’s board of directors and will depend on, among other things, the Company’s financial condition, results of operations, capital requirements, restrictions contained in future agreements and financing instruments, business prospects and such other factors as the Company’s board of directors may deem relevant.

Redeemable Convertible Preferre

Redeemable Convertible Preferred Stock	9 Months Ended
	Sep. 30, 2021
Temporary Equity Disclosure [Abstract]
Redeemable Convertible Preferred Stock	Redeemable Convertible Preferred Stock The Company had outstanding redeemable convertible preferred stock as follows (in thousands, except per share amounts): December 31, 2019 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0080 6,981 7,000 Series E 11,021 11,439 3.4968 39,906 40,000 Series F 11,772 12,218 5.3200 64,833 65,000 Series G 18,537 19,112 7.2539 137,291 138,636 Total 87,611 90,805 $ 290,365 $ 294,740 December 31, 2020 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $ 7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802 Financing Rounds of Preferred Stock In November 2019, 0.5 million shares or $3.6 million of the Series G preferred stock holdback, discussed in Note 3—Business Combinations, were released to former stockholders of DogBuddy. In February 2020, 9,000 shares or $0.1 million of the Series G preferred stock holdback were released to former stockholders of DogBuddy. Preferred Stock Provisions Dividends In any calendar year, the holders of outstanding shares of redeemable convertible preferred stock (Series A, B, C, D, D-1, E, F and G) shall be entitled to receive dividends when, as and if declared by the board of directors, out of any assets legally available for distributions at the time, at the dividend rate specified for such shares of preferred stock payable in preference and priority to any declaration or payment of any distribution on common stock of the Company in such calendar year. No distributions shall be made with respect to the common stock unless dividends on the preferred stock have been declared in accordance with the preferences and all declared dividends on the preferred stock have been paid or set aside for payment to the holders of preferred stock. The right to receive dividends on shares of preferred stock shall not be cumulative, and no right to dividends shall accrue to holders of preferred stock by reason of the fact that dividends on said shares are not declared or paid. Payment of any dividends to the holders of preferred stock shall be on a pro rata, pari passu basis in proportion to the dividend rates for each series of preferred stock. No additional dividends shall be declared on a series of preferred stock unless a pro rata per share amount is declared on each other series of preferred stock. Liquidation Preference The liquidation preference of the Company’s preferred stock is: Series A Liquidation Preference at $0.4478 per share; Series B Liquidation Preference at $0.6528 per share; Series C Liquidation Preference at $1.1238 per share; Series D Liquidation Preference at $2.0080 per share; Series D-1 Liquidation Preference at $2.0078 per share; Series E Liquidation preference at $3.4969 per share; Series F Liquidation at $5.3199 per share; and Series G Liquidation Preference at $7.2536 per share. In the event of any liquidation, dissolution or winding up of the Company, either voluntary or involuntary, the holders of the preferred stock shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Company to the holders of the common stock by reason of their ownership of such stock, (1) with respect to Series A preferred stock, an amount per share equal to the Series A Liquidation Preference plus any declared but unpaid dividends on such shares of Series A preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series A preferred stock; (2) with respect to Series B preferred stock, an amount per share equal to the Series B Liquidation Preference plus any declared but unpaid dividends on such shares of Series B preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series B preferred stock; (3) with respect to Series C preferred stock, an amount per share equal to the Series C Liquidation Preference plus any declared but unpaid dividends on such shares of Series C preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series C preferred stock; (4) with respect to Series D preferred stock, an amount per share equal to the Series D Liquidation Preference plus any declared but unpaid dividends on such share of Series D preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series D preferred stock; (5) with respect to Series D-1 preferred stock, an amount per share equal to the Series D-1 Liquidation Preference plus any declared but unpaid dividends on such shares of Series D-1 preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series D-1 preferred stock; (6) with respect to Series E preferred stock, an amount per share equal to the Series E Liquidation Preference plus any declared but unpaid dividends on such shares of Series E preferred stock, or such lesser amount as may be approved by the holders of the majority of the outstanding shares of Series E preferred stock; (7) with respect to the Series F preferred stock, an amount per share equal to the Series F Liquidation Preference plus any declared but unpaid dividends on such shares of Series F preferred stock, or such lesser amount as may be approved by the holders of at least 56% of the then outstanding shares of Series F preferred stock; and (8) with respect to the Series G preferred stock, an amount per share equal to the Series G Liquidation Preference plus any declared but unpaid dividends on such shares of Series G preferred stock, or such lesser amount as may be approved by the holders of at least two-thirds of the outstanding shares of Series G preferred stock. If upon the liquidation, dissolution or winding up of the Company, the assets of the Company’s legally available for distribution to the holders of the preferred stock are insufficient to permit the payment of the full amounts to such holders, then all of the assets of the Company’s legally available for distribution shall be distributed to the holders of preferred stock on pari passu basis in proportion to the preferential amount each such holder otherwise would have been entitled to receive in connection with the full payment of the preferential amounts. The preferred stock agreements contain provisions that, in the event of a change in the control of the Company, give the holders of the series of redeemable convertible preferred stock the right to receive a cash distribution equal to the liquidation preference on the redeemable convertible preferred stock. Due to these redemption characteristics, which are not solely within the Company’s control, the redeemable convertible preferred stock has been presented within the mezzanine section on the consolidated balance sheets. The Company does not adjust the carrying values of the redeemable convertible preferred stock to its deemed liquidation values since a liquidation event was not probable at any of the balance sheet dates. Subsequent adjustments to increase or decrease the carrying values to the ultimate liquidation values will be made only if and when it becomes probable that such a liquidation event will occur. Conversion Each share of preferred stock shall be convertible, at the option of the holder thereof, at any time after the date of issuance of such share, into that number of fully-paid, nonassessable shares of common stock determined by dividing the original issue price for the relevant series by the conversion price for such series. The current conversion ratio is on a 1:1 basis for Series A, Series B, Series C, Series D, Series D-1, Series E, Series F and Series G preferred stock. The conversion ratio shall be subject to appropriate adjustments for stock splits, stock dividends, combinations, subdivisions, or recapitalization events. In addition, if the Company should issue preferred stock or common stock without consideration or for a consideration per share less than the conversion price for the redeemable convertible preferred stock, the conversion price for each series shall automatically be adjusted in accordance with anti-dilution provisions contained in the Company’s amended and restated certificate of incorporation. As of December 31, 2019 and 2020, the applicable conversion price for each series of redeemable convertible preferred stock was the respective original issue price. Automatic Conversion Each share of preferred stock shall automatically be converted into fully-paid, nonassessable shares of common stock at the then effective conversion rate for such share: (1) immediately prior to the Effective Time of the first amended and restated certificate of incorporation filed by the Company with the Secretary of State of the State of Delaware after such time that a registration statement filed by the Company under the Securities Act of 1933, as amended, with the Securities and Exchange Commission is declared effective in connection with a firm commitment underwritten initial public offering for securities traded on the New York Stock Exchange, the NYSE American, Nasdaq market or another internationally recognized exchange, provided that the aggregate gross proceeds to the Company are not less than $50.0 million; or (2) in the case of the Series A, Series B, Series C and Series D-1 preferred stock (together, the “Additional Preferred Stock”), upon the receipt by the Company of a written request for such conversion from the holders of at least 70% of the then outstanding Additional Preferred Stock voting together as a single class on an as-converted to Common Stock basis, or in the case of Series D Preferred Stock, upon the receipt by the Company of a written request for such conversion from the holders of at a majority of the Series D preferred stock then outstanding, voting together as a separate class, or in the case of Series E preferred stock, upon the receipt by the Company of a written request for such conversion from the holders of at least a majority of the Series E preferred stock then outstanding, voting together as a separate class, or in the case of Series F preferred stock, upon the receipt by the Company of a written request for such conversion from the holders of at least 56% of the Series F preferred stock then outstanding, voting together as a separate class, or in the case of Series G preferred stock, upon the receipt by the Company of a written request for such conversion from the holders of at least two-thirds of the Series G preferred stock then outstanding, voting together as a separate class, in any case if later, the effective date for conversion specified in any such requests. Voting Each holder of preferred stock shall be entitled to the number of votes equal to the number of shares of common stock into which the shares of preferred stock held by such holder could be converted. Redemption Except in the case of a liquidation event, the preferred stock is not redeemable, in whole or in part.

Stock Warrants

Stock Warrants	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stock Warrants	Stock Warrants Public and Private Warrants Prior to the Merger, Caravel issued 5,166,667 Private Warrants and 5,500,000 Public Warrants. Upon the Closing of the Merger, 2,592,503 Private Warrants were forfeited. Each whole warrant entitles the holder to purchase one share of the Company’s Class A common stock at a price of $11.50 per share, subject to adjustments. The Warrants become exercisable on December 11, 2021 and terminate five years after the Closing. Once the Public Warrants become exercisable, the Company may redeem the outstanding warrants, in whole and not in part, upon a minimum of 30 days’ prior written notice of redemption (“Redemption Period”). The Company may redeem the outstanding Public Warrants for cash at a price of $0.01 per warrant if the Reference Value equals or exceeds $18.00 per share. The warrant holders have the right to exercise their outstanding warrants prior to the scheduled redemption date during the Redemption Period at $11.50 per share. If the Company calls the Public Warrants for redemption, the Company will have the option to require all holders that wish to exercise the Public Warrants to do so on a “cashless basis”, as described in the warrant agreement. For purposes of the redemption, “Reference Value” shall mean the last reported sales price of the Company’s Class A common stock for any twenty thirty The Private Warrants are identical to the Public Warrants except that the Private Warrants are not transferable, assignable or salable until 30 days after the completion of the Merger, subject to certain limited exceptions. Additionally, the Private Warrants are exercisable on a cashless basis and are non-redeemable so long as they are held by the initial purchasers or their permitted transferees. If the Private Warrants are held by someone other than the initial purchasers or their permitted transferees then such warrants will be redeemable by the Company and exercisable by the warrant holders on the same basis as the Public Warrants. On September 14, 2021, the Company filed a Registration Statement on Form S-1. This Registration Statement relates to, among other things, the registration of the offer and sale of the Private Warrants and the issuance of an aggregate of up to 8,074,164 shares of Class A common stock underlying the Warrants. As of September 30, 2021, there were 8,074,164 Warrants outstanding, and no Warrants had been exercised. Other Common Stock Warrants Legacy Rover also issued common stock warrants to various service providers, lenders, and investors, at various points in time, which were subsequently converted to common stock warrants of the Company. Upon consummation of the Merger, each Legacy Rover warrant that was outstanding was assumed by Caravel and converted into a common stock warrant exercisable for Class A common stock equal to the product (rounded down to the nearest whole number) of (1) the number of shares of Legacy Rover capital stock subject to the Legacy Rover warrant immediately prior to the Merger multiplied by (2) the Exchange Ratio. Such warrants have a per share exercise price equal to the quotient (rounded up to the nearest whole cent) obtained by dividing (1) the exercise price per share of Legacy Rover capital stock subject to the Legacy Rover warrant immediately prior to the Merger by (2) the Exchange Ratio, and, except as specifically provided in the Merger Agreement, each warrant continues to be governed by the same terms and conditions (including vesting and exercise terms) as were applicable to the corresponding former Legacy Rover warrant immediately prior to the Merger. Upon the Closing of the Merger, warrants to purchase 631,000 shares of common stock were net exercised resulting in the issuance of 448,000 shares of Class A common stock.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation 2011 Equity Incentive Plan On August 23, 2011, the Company adopted the 2011 Equity Incentive Plan (the “2011 Plan’’), which provides for the issuance of incentive and nonqualified stock options, restricted stock and other stock-based awards to employees, nonemployees, and directors of the Company. The Company reserved 29.0 million shares of common stock for issuance under the 2011 Plan. The board of directors administers the 2011 Plan and determines the exercise price of options, purchase price for restricted stock, the rates at which awards vest and the other terms and conditions of the awards. Options generally vest over four years and are subject to the employee’s continued employment with us. Options granted to consultants or other nonemployees generally vest over the expected service period to the Company. The options expire 10 years from the date of grant. The Company issues new shares to satisfy stock option exercises. Through December 31, 2020, only stock options had been issued under the 2011 Plan. Stock Options A summary of stock option activity is as follows (in thousands, except per share amounts and years): Options Available for Grant Number of Options Outstanding Weighted- Average Exercise Price Per Share Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Balances as of December 31, 2018 2,190 20,578 $ 1.27 7.4 Options authorized 7,203 — Options granted (6,897) 6,897 2.77 Options exercised — (966) 0.82 Options cancelled and forfeited 1,598 (1,598) 2.09 Balances as of December 31, 2019 4,094 24,911 $ 1.65 7.1 $ 34,776 Options authorized 1,801 — Options granted (1) (11,258) 11,258 2.08 Options exercised — (907) 0.85 Options cancelled and forfeited (1) 10,562 (10,562) 2.67 Balances as of December 31, 2020 5,199 24,700 $ 1.45 6.4 $ 83,570 'Options vested and exercisable –December 31, 2020 17,262 $ 1.20 5.5 $ 62,719 ________________ (1) Includes options that were canceled and re-granted as part of the option repricing modification, as further discussed below. The weighted-average grant-date fair value of options granted during the years ended December 31, 2018, 2019 and 2020 was $1.29, $1.51 and $0.59, respectively. The aggregate intrinsic value of stock options exercised during the years ended December 31, 2018, 2019 and 2020 was $3.4 million, $2.1 million and $2.4 million, respectively. The fair value of options vested during the years ended December 31, 2018, 2019 and 2020 was $2.2 million, $4.1 million and $5.0 million, respectively. As there is no public market for the Company’s common stock, the board of directors, with the assistance of a third-party valuation specialist, determined the fair value of the Company’s common stock at the time of the grant of share options by considering a number of objective and subjective factors, including the Company’s actual operating and financial performance, market conditions and performance of comparable publicly-traded companies, developments and milestones in the Company, the likelihood of achieving a liquidity event and transactions involving the Company’s common stock, among other factors. The fair value of the underlying common stock was determined by the board of directors. The fair value of the Company’s common stock was determined in accordance with applicable elements of the American Institute of Certified Public Accountants guide, Valuation of Privately Held Company Equity Securities Issued as Compensation. The following table presents the range of assumptions used to estimate the fair value of options granted during the periods presented: Year Ended December 31 2018 2019 2020 Risk-free interest rate 2.34% - 3.08% 1.38% - 2.60% 0.24% - 1.43% Expected term (years) 3.09 - 6.97 4.51 - 6.75 3.99 - 6.80 Volatility 44.5% - 50.6% 44.5% - 46.3% 49.0% - 54.8% Dividend yield — % — % — % Risk-Free Interest Rate— The risk-free interest rate is based on the U.S. Treasury yield in effect at the time the options are granted for zero coupon U.S. Treasury notes with maturities approximately equal to the expected term of the option. Expected Term —The expected term is based upon the Company’s consideration of the historical life of options, the vesting period of the option granted, and the contractual period of the option granted. The Company has a limited history of granting options, accordingly, the expected life was calculated using the simplified method. Volatility— As the Company is not publicly traded, the expected volatility for the Company’s stock options was determined by using an average of historical volatilities of selected industry peers deemed to be comparable to the Company’s business corresponding to the expected term of the awards. Dividend Yield— The expected dividend rate is zero as the Company currently has no history or expectation of declaring dividends on its common stock. Stock-Based Compensation The following table summarizes stock-based compensation expense recorded in each component of costs and expenses in the Company’s consolidated statements of operations for the presented periods (in thousands): Year Ended December 31 2018 2019 2020 Operations and support $ 206 $ 277 $ 299 Marketing 181 301 397 Product development 2,391 1,486 1,873 General and administrative 3,904 2,003 2,972 Total stock-based compensation expense $ 6,682 $ 4,067 $ 5,541 In 2018, stock-based compensation expense of $2.7 million and $1.5 million was recorded to general and administrative expense and product development expense, respectively, relating to a secondary market offering. Investors acquired 1.3 million shares of the Company’s common stock at a premium of $3.42 per share over the estimated fair value of the common stock at the time of the offering. Of the 1.3 million shares offered, 1.2 million shares were purchased from employees and 144,000 shares were purchased from non-employees. The premium attributable to the shares purchased from non-employees of $491,000 was recorded as a deemed dividend. No income tax benefit related to stock-based compensation was recorded during the years ended December 31, 2018, 2019 and 2020 as the Company maintained a full valuation allowance against its net deferred tax assets within the United States. As of December 31, 2020, total unrecognized compensation cost related to unvested stock options was $8.7 million, which was expected to be recognized over a weighted average remaining service period of 2.5 years. As of December 31, 2020, the Company had 5.2 million shares available for grant under the 2011 Plan. To the extent any of the stock options to purchase 553,000 shares of the Company’s common stock issuable pursuant to the assumed DogVacay stock option plan expire unexercised, a corresponding number of shares shall be automatically added to the 2011 Plan and shall be available for future grant pursuant to the terms thereof. To the extent any of the stock options to purchase 65,000 shares of the Company’s common stock issuable pursuant to the assumed DogBuddy stock option plan expire unexercised, a corresponding number of shares shall be automatically added to the 2011 Plan and shall be available for future grant pursuant to the terms thereof. Stock Option Modification During the year ended December 31, 2020, the Company experienced significant disruption to its business as a result of the rapid development of COVID-19 and the corresponding reduction in the demand for its marketplace services. In response to the impact of COVID-19, the Company implemented a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company amended the terms of stock options previously awarded to impacted employees. For employees who were terminated as part of the restructuring, the Company allowed pro-rata vesting of pre-cliff awards up to the termination date that would have otherwise been forfeited upon termination and extended the exercise period of vested stock options from 90 days to three years from the termination date. For employees who remained employed after the restructuring, the stock options were modified based on the fair value of the Company’s common stock as determined by the board of directors. As part of the restructuring, the Company modified 3,102,000 options held by terminated employees. The Company reversed the previously recognized expense for pre-cliff awards, recorded the incremental expense based on the modification-date fair value of awards that became vested under the pro-rata acceleration, and recorded any excess between the fair value of the vested awards immediately prior to and after the modification. The Company immediately recognized net incremental expense of $0.3 million related to these options. In July 2020, the Company modified 6,800,000 options held by then-current employees. The Company repriced options held by current employees with an exercise price greater than $1.99 per share. As part of the repricing, the original options were canceled and new options were granted with an exercise of $1.99 per share and a remaining contractual term of ten years. The new options were subject to the same service-based vesting schedule as the original options. The repricing was recorded as a stock option modification whereby the incremental fair value of each option was determined at the date of the modification and $0.4 million was immediately recognized related to vested options. During the year ended December 31, 2020, the Company recognized total stock-based compensation expense of $0.6 million related to these repriced options. As of December 31, 2020, there was remaining incremental fair value of $0.6 million which will be recognized over the remaining requisite service period. 2011 Equity Incentive Plan Legacy Rover’s 2011 Equity Incentive Plan (the “2011 Plan’’) allowed Legacy Rover to grant incentive and non-qualified stock options, restricted stock and other stock-based awards to employees, non-employees, and directors of Legacy Rover. In connection with the Closing of the Merger, the 2011 Plan was terminated, the remaining unallocated share reserve under the 2011 Plan was cancelled and no new awards will be granted under the 2011 Plan. 2021 Equity Incentive Plan In connection with the Closing of the Merger, the Company adopted the 2021 Equity Incentive Plan (the “2021 Plan”) under which 17.2 million shares of Class A common stock were initially reserved for issuance, plus up to 20.4 million shares subject to stock options that were assumed in the Merger and expire or otherwise terminate without having been exercised in full, are tendered to or withheld by the Company for payment of an exercise price or for tax withholding obligations, or are forfeited to or repurchased by the Company due to failure to vest. The 2021 Plan permits the grant of incentive and non-qualified stock options, restricted stock, restricted stock units and other stock-based awards to employees, directors, and consultants of the Company. As of September 30, 2021, the Company had 17.3 million shares of Class A common stock reserved for future issuance under the 2021 Plan, which includes shares subject to stock options that were assumed in the Merger that expired or otherwise terminated without having been exercised in full or were forfeited due to failure to vest. Upon the Closing, each option to purchase shares of Legacy Rover common stock that was outstanding, whether vested or unvested, was automatically converted into an option to purchase shares of the Company’s Class A common stock with the same terms except for the number of shares exercisable and the exercise price, using the exchange ratio of 1.2006 (“Option Exchange Ratio”). For periods prior to the Merger, the number of options and per share amounts have been retroactively converted by applying the Option Exchange Ratio. Stock Options A summary of stock option activity is as follows (in thousands, except per share amounts and years): Options Number of Weighted- Weighted- Aggregate Balances as of December 31, 2020 4,330 20,574 $ 1.74 6.4 $ 83,570 Retroactive application of reverse recapitalization 869 4,126 Balance as of December 31, 2020, as converted 5,199 24,700 $ 1.45 6.4 $ 83,570 Options authorized 17,200 Options exercised — (2,881) 1.08 Options cancelled in connection with termination of 2011 Plan (7,005) Options cancelled and forfeited 1,864 (1,864) 2.68 Balances as of September 30, 2021 17,258 19,955 $ 1.53 6.1 $ 240,692 Options vested and exercisable – September 30, 2021 15,369 $ 1.36 5.5 $ 187,904 The weighted-average grant-date fair value of options granted during the three and nine months ended September 30, 2020 was $0.21 and $0.49, respectively. There were no options granted during the nine months ended September 30, 2021. The aggregate intrinsic value of stock options exercised during the three and nine months ended September 30, 2021 was $14.5 million and $19.9 million, respectively, and was $0.2 million and $0.7 million during the three and nine months ended September 30, 2020, respectively. The fair value of options vested during the three and nine months ended September 30, 2021 was $0.9 million and $2.9 million, respectively, and was $1.2 million and $4.0 million during the three and nine months ended September 30, 2020, respectively. Stock-Based Compensation The following table summarizes stock-based compensation expense recorded in each component of operating expenses in the Company’s condensed consolidated statements of operations for the presented periods (in thousands): Three Months Ended September 30, Nine Months Ended 2020 2021 2020 2021 Operations and support $ 100 $ 43 $ 261 $ 144 Marketing 123 71 348 238 Product development 510 287 1,459 981 General and administrative 1,056 593 2,200 1,779 Total stock-based compensation expense $ 1,789 $ 994 $ 4,268 $ 3,142 No income tax benefit related to stock-based compensation was recorded during the three and nine months ended September 30, 2021 and 2020 as the Company maintained a full valuation allowance against its net deferred tax assets within the United States. As of September 30, 2021, total unrecognized compensation cost related to unvested stock options was $5.3 million, which was expected to be recognized over a weighted average remaining service period of 1.9 years. Stock Option Modification During the year ended December 31, 2020, the Company experienced significant disruption to its business as a result of the rapid development of COVID-19 and the corresponding reduction in the demand for its marketplace services. In response to the impact of COVID-19, the Company implemented a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company amended the terms of stock options previously awarded to impacted employees. For employees who were terminated as part of the restructuring, the Company allowed pro-rata vesting of pre-cliff awards up to the termination date that would have otherwise been forfeited upon termination and extended the exercise period of vested stock options from 90 days to three years from the termination date. For employees who remained employed after the restructuring, the stock options were modified based on the fair value of the Company’s common stock as determined by the board of directors. In April 2020, the Company modified options to exercise 3,100,000 shares held by terminated employees. The Company reversed the previously recognized expense for pre-cliff awards, recorded the incremental expense based on the modification-date fair value of awards that became vested under the pro-rata acceleration, and recorded any excess between the fair value of the vested awards immediately prior to and after the modification. The Company immediately recognized net incremental expense of $0.3 million related to these options. In July 2020, the Company modified options to exercise 6,800,000 shares held by then-current employees. The Company repriced options held by current employees with an exercise price greater than $1.99 per share. As part of the repricing, the original options were canceled and new options were granted with an exercise of $1.99 per share and a remaining contractual term of ten years. The new options were subject to the same service-based vesting schedule as the original options. The repricing was recorded as a stock option modification whereby the incremental fair value of each option was determined at the date of the modification and $0.4 million was immediately recognized related to vested options. During the three and nine months ended September 30, 2021, the Company recognized total stock-based compensation expense of $0.1 million and $0.3 million related to these repriced options, respectively. For the three and nine ended September 30, 2020, the Company recognized total stock-based compensation expense of $0.5 million related to these repriced options. As of September 30, 2021, there was remaining incremental fair value of $0.4 million which will be recognized over the remaining requisite service period.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following table presents the components of loss before income taxes (in thousands): Year Ended December 31, 2018 2019 2020 U.S. (63,467) (48,650) (56,758) Foreign (1,479) (3,532) (821) Total (64,946) (52,182) (57,579) The following table presents the components of the (provision for) benefit from income taxes (in thousands): Year Ended December 31, 2018 2019 2020 Current tax expense: U.S. Federal $ — $ — $ — State — (29) (5) Foreign (9) (91) (204) Total current (9) (120) (209) Deferred tax expense: U.S. Federal — — — State — — — Foreign 278 588 303 Total deferred tax benefit 278 588 303 Total income tax benefit $ 269 $ 468 $ 94 The following table presents a reconciliation of the statutory federal rate to the Company’s effective tax rate: Year Ended December 31, 2018 2019 2020 Federal income taxes at statutory rate 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 1.8 1.7 1.6 Tax credits 1.3 1.6 0.2 Equity compensation (1.1) (1.0) (0.9) Change in valuation allowance (21.3) (20.6) (20.9) Other, net (1.3) (1.8) (0.8) Effective income tax rate 0.4 % 0.9 % 0.2 % The following table presents the significant components of the Company’s deferred tax assets and liabilities (in thousands): December 31, 2019 2020 Deferred tax assets: Net operating loss carryforward $ 46,810 $ 55,649 Tax credit carryforward 2,199 2,298 Reserves and accruals 1,030 909 Stock based compensation 498 1,011 Property, plant and equipment — 214 Other 21 898 Total deferred tax assets 50,558 60,979 Less: Deferred tax assets valuation allowance (45,180) (57,225) Total deferred tax assets, net of valuation allowance 5,378 3,754 Deferred tax liabilities: Capitalized internal-use software costs (3,223) (2,477) Intangibles (1,076) (42) Property, plant and equipment (153) — Total deferred tax liabilities (4,452) (2,519) Net deferred tax assets $ 926 $ 1,235 The following table presents a rollforward of the valuation allowance (in thousands): Year Ended December 31, 2018 2019 2020 Balance at beginning of period $ 20,620 $ 34,435 $ 45,180 Increase in valuation allowance 13,815 10,745 12,045 Balance at end of period $ 34,435 $ 45,180 $ 57,225 As of December 31, 2020, the Company had federal net operating loss carryforwards of $234.8 million, state net operating loss carryforwards of $80.5 million and foreign net operating loss carryforwards of $6.4 million which may be available to reduce future taxable income. The gross federal net operating loss (“NOL”) carryforwards generated during and after 2018 totaling $134.2 million are carried forward indefinitely, while all others, if not utilized, will expire beginning in 2031. The gross state NOL carryforwards will expire beginning in 2025. Realization of deferred tax assets is dependent upon the generation of future taxable income, if any, the timing and amount of which are uncertain. The Company has recorded a full valuation allowance against its net U.S. deferred tax assets as of December 31, 2019 and 2020 because, based on the weight of available evidence, it is more-likely-than-not (a likelihood of more than 50%) that some or all of the deferred tax assets will not be realized. The Company is open to examination by the U.S. federal tax jurisdiction for the years ended December 31, 2017 through 2020. The Company is also open to examination for 2011 and forward with respect to U.S. federal net operating loss carryforwards generated and carried forward from those years. There are currently no federal or state income tax audits in process. The NOLs are subject to review and possible adjustment by the IRS and state tax authorities. NOL carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders over a three-year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has not yet conducted a study to determine if any such changes have occurred that could limit the Company’s ability to use the net operating losses and tax credit carryforwards. In the event the Company experienced an ownership change, or should experience an ownership change in the future, the amount of net operating loss and tax credit carryforwards available in any taxable year could be limited and may expire unutilized. A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2018 2019 2020 Beginning of period $ 218 $ 383 $ 550 Current year tax position increases 165 167 24 End of period $ 383 $ 550 $ 574 The gross unrecognized tax benefits as of December 31, 2018, 2019 and 2020, if recognized, would not affect the effective tax rate as these unrecognized tax benefits would increase deferred tax assets that would be subject to a full valuation allowance. No material changes in the gross unrecognized tax benefits are expected over the next twelve months. The Company’s tax provision for interim periods is determined using an estimated annual effective tax rate, adjusted for discrete items in the related period. The effective tax rate for the three months ended September 30, 2021 and 2020 was 0.0% and 0.7%, respectively, and 0.3% and 0.2% for the nine months ended September 30, 2021 and 2020, respectively. The change in effective tax rate is primarily due to a discrete item in the second quarter of 2021 related to the enacted tax law change which increased the general United Kingdom tax rate from 19.0% to 25.0%, effective April 1, 2023 and the effect of U.S. losses being excluded from the Company’s estimated annual effective tax rate due to recording a full valuation allowance on the U.S. deferred tax assets. During the three and nine months ended September 30, 2021, the amount of gross unrecognized tax benefits increased by $5 thousand and $12 thousand, respectively, of which all, if recognized, would not affect the effective tax rate as these unrecognized tax benefits would increase deferred tax assets that would be subject to a full valuation allowance.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	Net Loss Per Share Attributable to Common Stockholders The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except per share amounts): Year Ended December 31, 2018 2019 2020 Numerator: Net loss $ (64,677) $ (51,714) $ (57,485) Deemed dividend to preferred stockholders (491) — — Net loss attributable to common stockholders $ (65,168) $ (51,714) $ (57,485) Denominator: Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, basic and diluted 27,150 29,138 29,896 Net loss per share attributable to common stockholders, basic and diluted $ (2.40) $ (1.77) $ (1.92) The following potentially dilutive shares were not included in the calculation of diluted shares outstanding for the periods presented as the effect would have been anti-dilutive (in thousands): Year Ended December 31, 2018 2019 2020 Redeemable convertible preferred stock 90,305 90,805 90,814 Outstanding stock options 20,578 24,911 24,700 Outstanding common stock warrants 674 790 1,118 Total 111,557 116,506 116,632 The following table sets forth the computation of basic and diluted net loss per common share attributable to common stockholders (in thousands, except share and per share data): Three Months Ended September 30, Nine Months Ended 2020 2021 2020 2021 Numerator: Net loss $ (10,359) $ (84,536) $ (48,983) $ (97,933) Denominator: Weighted-average shares used to compute basic and diluted net loss per share 30,008 116,597 29,834 59,825 Net loss per common share - basic and diluted $ (0.35) $ (0.73) $ (1.64) $ (1.64) As a result of the Merger, the weighted-average number of shares of Class A common stock used in the calculation of net loss per share have been retroactively converted by applying the Exchange Ratio. The following potentially dilutive shares were not included in the calculation of diluted shares outstanding for the periods presented as the effect would have been anti-dilutive (in thousands): September 30, 2020 2021 Redeemable convertible preferred stock 90,814 — Outstanding stock options 25,481 19,955 Outstanding common stock warrants 1,118 — Private Warrants — 2,574 Public Warrants — 5,500 Sponsor Earnout Shares — 492 Total 117,413 28,521 The 2,192,687 remaining unvested Rover Earnout Shares are excluded from basic and diluted net loss per share as such shares are contingently issuable until the share price of the Company’s common stock exceeds specified thresholds that have not been achieved as of September 30, 2021.

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Restructuring	RestructuringDuring the year ended December 31, 2020, the Company experienced significant disruption to its business in 2020 as a result of the rapid development of COVID-19 and the corresponding reduction in the demand for its marketplace services. In response to the impact of COVID-19, the Company implemented a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company incurred severance-related and legal costs of $3.8 million, as well modified the terms of stock options previously awarded to impacted employees (see Note 14—Stock-Based Compensation). As of December 31, 2020, there was no remaining liability for restructuring-related costs. The following table summarizes restructuring charges recorded in each component of costs and expenses in the Company’s consolidated statements of operations (in thousands): December 31, 2020 Operations and support $ 796 Marketing 593 Product development 1,743 General and administrative 631 Total restructuring charges $ 3,763 In response to the impact of COVID-19, the Company implemented a restructuring plan in April 2020 whereby approximately 50% of employees were terminated or placed on standby. In connection with this restructuring, the Company incurred total severance-related and legal costs of $3.8 million, as well as modified the terms of stock options previously awarded to impacted employees (see Note 12—Stock-Based Compensation). As of September 30, 2021 and December 31, 2020, there was no remaining liability for restructuring-related costs. The following table summarizes restructuring charges recorded in each component of costs and expenses in the Company’s condensed consolidated statements of operations (in thousands): Three Months Ended Nine Months Ended Operations and support $ 174 $ 795 Marketing 84 592 Product development 138 1,741 General and administrative 116 623 Total restructuring charges $ 512 $ 3,751 There were no restructuring charges recorded in costs and expenses in the Company’s condensed consolidated statements of operations for the three and nine months ended September 30, 2021.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated subsequent events through March 29, 2021, the date the financial statements were available to be issued and has determined that the following subsequent events require disclosure in the consolidated financial statements. In February 2021, the Company entered into a Business Combination Agreement and Plan of Merger (as it may be amended or restated from time to time, the “Business Combination Agreement”) with Nebula Caravel Acquisition Corp. (“Caravel”) and Fetch Merger Sub, Inc. (“Sub”), a wholly owned subsidiary of Caravel. Pursuant to the terms of the Business Combination Agreement, Merger Sub will merge with and into Rover, with Rover continuing as the surviving entity (the “Merger”). Concurrently with the execution and delivery of the Business Combination Agreement, certain accredited investors (the “PIPE Investors”), entered into subscription agreements (the “PIPE Subscription Agreements”) with Caravel pursuant to which the PIPE Investors have committed to purchase 5,000,000 shares (the “PIPE Shares”) of Caravel Class A Common Stock (the “Caravel Class A Common Stock”) at a purchase price per share of $10.00 and an aggregate purchase price of $50,000,000 (the “PIPE Investment”). The purchase of the PIPE Shares is conditioned upon, among other conditions, and will be consummated concurrently with, the closing of the Merger (the “Closing”). In March 2021, the Company renegotiated the overall liquidity covenant on its credit facility with the lender to $65.0 million. Events subsequent to Original Issuance of Consolidated Financial Statements (unaudited) At closing of the Merger, legacy stockholders of the Company were entitled to receive up to 19,734,183 shares (“Rover Earnout Shares”) of Class A common stock subject to the occurrence of certain triggering events and the Sponsor subjected 2,461,627 shares (“Sponsor Earnout Shares”) to vesting and potential forfeiture (and related transfer restrictions) based on a seven year post-Closing earnout. Certain of the triggering events occurred on September 29, 2021 resulting in the vesting of 1,969,302 Sponsor Earnout Shares on September 29, 2021, and the vesting of 17,540,964 Rover Earnout Shares on September 29, 2021 which were subsequently issued on October 6, 2021.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation and Basis of PresentationThe consolidated financial statements and accompanying notes include the accounts of the Company and its wholly owned subsidiaries, after elimination of all intercompany balances and transactions.
Basis of Presentation	The Company has prepared the consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”).
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated balance sheet and the reported amounts of revenue and expenses during the reporting period. Significant items subject to such estimates and assumptions, include, but are not limited to, the capitalization and estimated useful life of the Company’s internal-use software development costs and the assumptions used in the valuation of common and preferred stock. These estimates and assumptions are based on information available as of the date of the consolidated financial statements; therefore, actual results could differ from management’s estimates. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. The Company adjusts such estimates and assumptions when facts and circumstances dictate. Changes in those estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods. As future events and their effects cannot be determined with precision, actual results could materially differ from those estimates and assumptions.
Net Loss per Share Attributable to Common Stockholders	Net Loss per Share Attributable to Common Stockholders The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. The Company’s redeemable convertible preferred stock contractually entitles the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in the Company’s losses. As such, net losses for the periods presented were not allocated to these securities.
Segment Information	Segment Information The Company has one operating segment and one reportable segment. As the Company’s chief operating decision maker, the Chief Executive Officer reviews financial information on a consolidated basis for purposes of allocating resources and evaluating financial performance. Substantially all long-lived assets are located in the United States and substantially all revenue is attributed to fees from pet parents and pet service providers based in the United States.
Foreign Currencies	Foreign CurrenciesThe functional currency for the Company’s foreign subsidiaries is either the U.S. dollar or the local currency depending on the assessment of management. An entity’s functional currency is determined by the currency of the economic environment in which the majority of cash is generated and expended by the entity. The financial statements of all majority-owned subsidiaries and related entities with functional currencies other than the U.S. dollar have been translated into U.S. dollars. All assets and liabilities of the respective entities are translated at year-end exchange rates and all revenue and expenses are translated at average rates during the respective period. Translation adjustments are reported as other comprehensive income (loss) in the consolidated statements of comprehensive loss. Foreign currency transaction gains and losses are a result of the effect of exchange rate changes on transactions denominated in currencies other than the functional currency, including U.S. dollars. Gains and losses on those foreign currency transactions are included in determining net loss for the period of exchange and are recorded in other income (expense), net in the consolidated statements of operations.
Certain Significant Risks and Uncertainties	Certain Significant Risks and Uncertainties The Company is subject to certain risks and challenges associated with other companies at a similar stage of development, including risks associated with: dependence on key personnel; marketing; adaptation to changing
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with stated maturities of three months or less from the date of purchase to be cash equivalents. As of December 31, 2019, and 2020, cash equivalents primarily consisted of money market fund investments.
Accounts Receivable	Accounts Receivable Accounts receivable primarily include funds collected by payment processors on the Company’s behalf from pet parents and pet service providers, net of an allowance for doubtful accounts. Bad debt expense and the allowance for doubtful accounts were not material for any of the periods presented.
Short term Investment	Short-term Investments The Company classifies its investments in debt securities as available-for-sale. Investment securities are stated at fair value with any unrealized gains or losses included as a component of accumulated other comprehensive income (loss) in stockholders’ deficit. Realized gains and losses and declines in the value of securities judged to be other-than-temporary are included in other income (expense), net in the consolidated statements of operations. The Company regularly reviews investments for other-than-temporary impairment using both qualitative and quantitative criteria. When assessing short-term investments for other-than-temporary declines in value, the Company considers factors such as, among other things, the extent and length of time the investment’s fair value has been lower than its cost basis, the financial condition and near-term prospects of the investee, the Company’s ability and intent to retain the investment for a period of time sufficient to allow for any anticipated recovery in fair value, and the expected cash flows from the security. If any adjustment to fair value reflects a decline in the value of the investment that the Company considers to be “other than temporary,” the Company reduces the investment to fair value through a charge to the consolidated statements of operations and consolidated statements of comprehensive loss. No such adjustments were necessary during the periods presented. The cost of investments for purposes of computing realized and unrealized gains and losses is based on the specific identification method. Dividend and interest income, and any amortization of premiums and accretion of discounts to maturity are included in interest income, net in the consolidated statement of operations. The Company considers all available-for-sale debt securities, including those with maturity dates beyond 12 months, as available to support current operational liquidity needs, and therefore, classifies all securities that are not classified as cash and cash equivalents as current assets in the consolidated balance sheets. The interest earned on short-term investments is recorded in interest income in the consolidated statements of operations.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, consist of cash, investments and accounts receivable. The Company maintains cash balances that may exceed the insured limits set
Comprehensive Loss	Comprehensive Loss Certain gains and losses are recognized in comprehensive loss but excluded from net loss. Comprehensive loss includes net loss, unrealized gains and losses on available-for-sale debt securities and foreign currency translation adjustments.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels that are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1— Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2— Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3— Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the specific asset or liability. The Company recognizes transfers between levels within the fair value hierarchy, if any, at the end of each period. There were no transfers between levels during the periods presented. The carrying values of the Company’s cash equivalents, accounts receivable, accounts payable, and accrued expenses and other current liabilities approximate fair value based on the highly liquid, short-term nature of these instruments. The carrying amount of the Company’s outstanding debt approximates the fair value as the debt bears a floating rate that approximates the market interest rate.
Property and Equipment net	Property and Equipment, net Property and equipment are stated at cost and are depreciated or amortized using the straight-line method over the estimated useful lives of the assets. Depreciation provisions are based upon the following estimated useful lives: Asset Category Depreciation Period Computers 3 years Furniture and fixtures 5-7 years Leasehold improvements Shorter of estimated useful life of asset or remaining lease term Upon retirement or sale, the cost of disposed assets, and the related accumulated depreciation, is removed from the accounts and any resulting gain or loss is reflected in other income (expense), net in the consolidated statements of operations. Expenditures for maintenance and repairs are charged to expense as incurred, whereas additions and improvements that increase the value or extend the life of an asset are capitalized to property and equipment.
Internal-Use Software	Internal-Use Software Costs incurred to develop the Company’s website and software for internal use are capitalized and amortized over its estimated useful life. Capitalization of costs to develop software begin when preliminary development efforts are successfully completed, management has authorized and committed project funding and it is probable that the project will be completed, and the software will be used as intended. The Company also capitalizes costs related to upgrades and enhancements when it is probable the expenditures will result in significant additional functionality or will extend the useful life of existing functionality. Costs related to the design or maintenance of website development and internal-use software are expensed as incurred. The Company periodically reviews website development and internal-use software costs to determine whether the projects will be completed, placed in service, removed from service or replaced by other internally developed or third-party software. If the asset is not expected to provide any future use, the asset is retired, and any unamortized cost is expensed. Internal-use software is amortized on a straight-line basis over its estimated useful life, generally three years. Management evaluates the useful lives of these assets on an annual basis and tests for impairment whenever events or changes in circumstances occur that could impact the recoverability of these assets. Management has determined that there has been no impairment of previously capitalized costs during 2018, 2019 and 2020. The Company capitalized $6.2 million, $11.9 million and $7.0 million of software development costs during the years ended December 31, 2018, 2019 and 2020, respectively. Stock-based compensation costs included in capitalized internal-use software development costs were not material for the years ended December 31, 2018, 2019 and 2020. The Company recorded amortization expense for capitalized internal use software of $2.5 million, $5.2 million and $7.2 million for the years ended December 31, 2018, 2019 and 2020, respectively, which is included in cost of revenue (exclusive of depreciation and amortization shown separately) in the consolidated statements of operations. Capitalized website development and internal-use software costs are included in property and equipment, net in the consolidated balance sheets.
Business Combinations	Business Combinations The results of businesses acquired in a business combination are included in the Company’s consolidated financial statements from the date of acquisition. The Company allocates the purchase price of a business combination, which is the sum of the consideration provided and may consist of cash, equity or a combination of the two, to the identifiable assets acquired and liabilities assumed of the acquired business at their acquisition date fair values. The excess of the purchase price over the amount allocated to the identifiable assets and liabilities, if any, is recorded as goodwill. Determining the fair value of assets acquired and liabilities assumed requires management to use judgment and estimates, including the selection of valuation methodologies, cost of capital estimates of future revenue and cash flows, discount rates, and selection of comparable companies, among others. The Company’s estimates of fair value are based on assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. During the measurement period, not to exceed one year from the date of acquisition, the Company may record adjustments to the assets acquired and liabilities assumed, with a corresponding offset to goodwill. When the Company issues stock-based or cash awards to an acquired company’s stockholders, the Company evaluates whether the awards are contingent consideration or compensation for post-combination services. The evaluation includes, among other things, whether the vesting of the awards is contingent on the continued employment of the acquired company’s stockholder beyond the acquisition date. If continued employment is required for vesting, the awards are treated as compensation for post-combination services and recognized as expense over the requisite service period. Acquisition-related transaction costs are expensed in the period in which the costs are incurred and included in general and administrative expense in the Company consolidated statements of operations.
Goodwill	Goodwill Goodwill represents the excess of the aggregate fair value of the consideration transferred in a business combination over the fair value of the assets acquired, net of liabilities assumed. Goodwill is not amortized, but is subject to an annual impairment test. Management has determined that the Company has a single reporting unit and performs its annual goodwill impairment test as of October 31, or more frequently if events or changes in circumstances indicate that the goodwill may be impaired. Events or changes in circumstances which could trigger an impairment review include significant changes in the manner of the Company’s use of the acquired assets or the strategy for the Company’s overall business, significant negative industry or economic trends, significant underperformance relative to historical or projected future results of operations, a significant adverse change in the business climate, cost factors that have a negative effect on earnings and cash flows, an adverse action or assessment by a regulator, estimated per share fair value of common stock, unanticipated competition or a loss of key personnel. The Company has the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is not more-likely-than-not that the fair value of the reporting unit is less than its carrying amount, then additional impairment testing is not required. However, if the Company concludes otherwise, then it is required to perform a quantitative assessment for impairment. The quantitative assessment involves comparing the estimated fair value of the reporting unit with its respective book value, including goodwill. If the estimated fair value exceeds book value, goodwill is considered not to be impaired and no additional steps are necessary. If, however, the book value of the reporting unit exceeds the fair value, an impairment loss is recognized in an amount equal to the excess, not to exceed the total amount of goodwill allocated to that reporting unit. The Company completed a qualitative analysis as of October 31, 2018 and 2019. The Company experienced significant disruption to its business in 2020 as a result of the rapid development of COVID-19 and the corresponding reduction in the demand for its marketplace services. The Company completed qualitative analyses as of March 31, 2020, June 30, 2020, September 30, 2020, and October 31, 2020. No impairment of goodwill was recognized during any of the periods presented.
Intangible Assets	Intangible Assets Intangible assets are amortized over the estimated useful life of the assets. Amortization of intangible assets associated with or used in the services provided by the Company from which it generates revenue are classified within cost of revenue (exclusive of depreciation and amortization shown separately) in the Company’s statements of operations. Amortization of intangible assets not associated with or used in the services provided by the Company from which it generates revenue are classified within depreciation and amortization expense within the Company’s statements of operations. For the periods presented, amortization of the Company’s capitalized internal-use software costs related to its online platform has been included within costs of revenues. For the periods presented, amortization expense related to other intangible assets have been classified within depreciation and amortization within the Company’s statement of operations. The Company reviews intangible assets for impairment under the long-lived asset model described below. No impairment of intangible assets was recorded during any of the periods presented.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be fully recoverable. When such events occur, management determines whether there has been impairment by comparing the anticipated undiscounted future net cash flows to the carrying value of the asset or asset group. If impairment exists, the assets are written down to its estimated fair value. There was no impairment of long-lived assets for any of the periods presented.
Revenue Recognition	Revenue Recognition (Topic 606) The Company operates an online marketplace that provides a platform for pet parents and pet service providers to communicate and arrange for pet services. The Company derives its revenue principally from pet parents’ and pet service providers’ use of the Company’s platform and related services that enable pet service providers to offer, book and fulfill pet services. Additionally, the Company earns revenue from fees paid by pet service providers for background checks in order to use the Company’s platform. The Company enters into terms of service with pet service providers and pet parents who wish to use the Company’s platform. The terms of service define the pet service providers’ rights and responsibilities when using the Company’s platform as well as general payment terms. The Company charges a fixed percentage service fee for each arrangement of pet services between the pet parent and the pet service provider on the Company’s platform (a booking). The fixed percentage service fees are established at the time a pet parent or pet provider joined the platform and do not vary based on the volume of transactions. A booking defines the explicit fee from which the Company earns its fixed percentage service fee. The creation of a booking combined with the terms of service establish enforceable rights and obligations for the transaction. A contract exists between the pet service provider and the Company upon the creation of a booking and after the pet service providers’ cancellation period has lapsed. Pet parents are considered the Company’s customers to the extent that they pay a fixed percentage fee to the Company for the booking. Similarly, a contract exists between the pet parent and the Company upon the creation of a booking and after the pet service providers’ cancellation period has lapsed. Pet parents pay for services at the time of booking. The Company considers the facilitation of the connection between pet service provider and pet parent to be the promise in the contracts. This is consistent with the terms of service, as well as the substance of what a pet service provider or pet parent is expecting from the use of the Company’s platform. While customers have access to the use of the platform, customer support, and other activities, these activities are not considered distinct from each other in the context of the overall arrangement, which is the facilitation of a connection between a pet service provider and a pet parent. As such, the Company has determined that its sole performance obligation is to facilitate a connection between pet service providers and pet parents through its platform. The Company’s performance obligation is satisfied at a point-in-time when the connection has been completed, which is when the pet service provider and pet parent have completed a booking, any related cancellation period has lapsed, and the related underlying pet services have begun. The Company derives revenue from pet service providers and pet parents primarily in the United States, as well as Canada and Europe. Revenue related to background checks is recorded upon completion of the related background check. From time to time, the Company issues credits or refunds to its pet parents or pet service providers as a result of customer satisfaction matters. Such amounts have historically been immaterial. Judgment is required in determining whether the Company is the principal or agent in transactions with pet service providers and pet parents. The Company evaluates the presentation of revenue on a gross or net basis based on whether it controls the service provided to the pet parent and is therefore the principal, or the Company arranges for other parties to provide the service to the pet parent and is therefore the agent. The Company has concluded it is the agent in transactions with pet service providers and pet parents because, among other factors, it is not responsible for the delivery of pet services provided by the pet service provider to the pet parent. Accordingly, the Company recognizes revenue on a net basis, representing the fee the Company expects to receive in exchange for providing the access to the Company’s platform to pet service providers and pet parents. The Company has no significant financing components in its contracts with customers. The Company recognizes revenue net of any sales tax paid related to its revenue transactions. Revenue Recognition (Prior to adoption of Topic 606) The Company recognizes revenue when (i) persuasive evidence of an arrangement exists, (ii) services provided by the Company have been rendered, (iii) the amount of fees to be paid by the Company’s customer is fixed or determinable, and (iv) the collection of fees is reasonably assured. Revenue related to marketplace services is recognized as the Company’s services are provided when the pet service provider and pet parent have completed a booking, any related cancellation period has lapsed, and the related underlying pet service have begun. Revenue related to background checks is recorded upon completion of the related background check. The Company evaluates whether it is appropriate to recognize revenue on a gross or net basis based upon its evaluation of whether it is the primary obligor in a transaction, has inventory risk and has latitude in establishing pricing and selecting suppliers, among other factors. The Company primarily derives revenue from two sources: 1) percentage-based fees charged to pet service providers for services that were arranged on the marketplace, and 2) percentage-based fees charged to pet parents for services arranged on the marketplace. Revenue related to these fees is recognized ratably over the period pet services are provided, which matches the Company’s obligation to provide support to both pet parents and pet service providers over the service period.
Pet Parent Discounts	Pet Parent Discounts The Company offers discounts to pet parents to encourage use of the Company’s platform. Discounts are primarily in the form of coupon codes for prospective pet parents and are accounted for as reductions to revenue.
Deferred Revenue Policy Policy Text Block	Deferred Revenue Deferred revenue represents payment received from pet parents in advance of the related performance obligation being satisfied and revenue being recognized and could be subject to return to pet parents upon the cancellation of the booking prior to fulfilment of the Company’s performance obligation based on the applicable terms of service.
Pet Parent Deposits and Pet Service Provider Liabilities	Pet Parent Deposits and Pet Service Provider Liabilities The Company records payments received from pet parents, excluding the revenue portion due to the Company, in advance of the related services being provided as pet parent deposits. As the related performance obligations are satisfied, these amounts are reclassified from pet parent deposits to pet service provider liabilities in the consolidated balance sheets. The Company is subject to compliance with escheat laws applicable by jurisdiction where pet service providers do not claim the amounts owed to them for services rendered.
Cost of Revenue (Exclusive of Depreciation and Amortization Shown Separately)	Cost of Revenue (Exclusive of Depreciation and Amortization Shown Separately)Cost of revenue (exclusive of depreciation and amortization shown separately) includes fees paid to payment processors for credit card and other funding transactions, server hosting costs, internal-use software amortization, third-party costs for background checks for pet care providers, claim costs paid out under the Rover Guarantee (“Rover Guarantee”) and other direct and indirect costs arising as a result of bookings that take place on our platform.
Operations and Support	Operations and Support Operations and support expenses include payroll, employee benefits, stock-based compensation and other personnel-related costs associated with the Company’s operations and support team, and third-party costs related to outsourced support providers. This team assists with onboarding new pet care providers, quality reviews of pet care
Marketing	MarketingMarketing expenses include payroll, employee benefits, stock-based compensation expenses and other personnel-related costs associated with the Company’s marketing team. These expenses also include digital marketing, brand marketing, public relations, broadcast television, marketing partnerships and other promotions. Digital marketing primarily consists of targeted promotional campaigns through electronic channels, such as social media, search engine marketing, affiliate programs and display advertising, all of which are primarily focused on pet parent acquisition and brand marketing. Except for content creation, advertising expenses are expensed as incurred, and are included in marketing expenses on the consolidated statements of operations. The Company allocates a portion of overhead costs which includes lease expense, utilities and information technology expense to marketing expense based on headcount. Advertising expenses were $47.6 million, $37.9 million and $8.1 million during the years ended December 31, 2018, 2019 and 2020, respectively.
Product Development	Product DevelopmentProduct development expenses include payroll, employee benefits, stock-based compensation expense and other headcount-related costs for employees in engineering, design and product management, as well as maintenance and support costs for technology infrastructure, primarily related to non-revenue generating systems. Product development costs, except qualifying costs related to the development of internal-use software, are expensed as incurred. The Company allocates a portion of overhead costs which includes lease expense, utilities and information technology costs to product development expense based on headcount.
General and Administrative	General and Administrative General and administrative expenses include payroll, employee benefits, stock-based compensation expense and other personnel-related costs for employees in corporate functions, such as management, accounting, and legal as well as insurance and other expenses used to run the business. The Company allocates a portion of overhead costs which includes lease expense, utilities and information technology costs to general and administrative expense based on headcount.
Depreciation and Amortization	Depreciation and Amortization Depreciation and amortization expenses include depreciation of our property and equipment, leasehold improvements and amortization of intangible assets. Amortization related to internal-use software is included in cost of revenue (exclusive of depreciation and amortization shown separately).
Restructuring Charges	Restructuring Charges Costs and liabilities associated with restructuring are recorded in the period management commits to a restructuring or cost reduction plan, or executes specific actions contemplated by the plan and all criteria for liability recognition have been met. One-time employee termination costs are recognized at the time of communication to employees, unless future service is required, in which case the costs are recognized ratably over the future service period. Ongoing employee termination benefits are recognized as a liability when it is probable that a liability exists and the amount is reasonably estimable. Restructuring charges are recognized as an operating expense within the consolidated statements of operations and related liabilities are recorded within accrued compensation and related expenses on the consolidated balance sheets. The Company periodically evaluates and, if necessary, adjusts its estimates based on currently available information.
Interest Expense	Interest Expense Interest expense consists primarily of interest expense incurred under debt borrowings.
Loss Contingencies	Loss Contingencies Liabilities for loss contingencies arising from claims, assessments, litigation, fine, and penalties and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably be estimated. Legal costs for loss contingencies are expensed as incurred.
Rent Expense and Lease Hold Improvements	Rent Expense and Leasehold Improvements Rent expense for leases that provide for scheduled rent increases or free rent periods during the lease term are recognized on a straight-line basis over the term of the related leases. Certain leasehold improvements are funded by landlord incentives or allowances. Such incentives or allowances under operating leases are recorded as a component of other noncurrent liabilities and are amortized as a reduction of rent expense over the term of the related lease. The current portion of deferred rent is presented in accrued expenses and other current liabilities in the consolidated balance sheets. Rent expense and amortization of leasehold improvements are allocated to the different costs and expenses presented in the consolidated statements of operations.
Stock-Based Compensation	Stock-Based Compensation The Company grants stock option awards to certain employees and non-employee directors. The Company accounts for stock-based compensation expense by calculating the estimated fair value of each award at the grant date or modification date by applying the Black-Scholes option pricing model. The model utilizes the estimated per share fair value of the Company’s underlying common stock at the measurement date, the expected or contractual term of the option, the expected stock price volatility, risk-free interest rates, and the expected dividend yield of the common stock. Stock-based compensation expense is recognized on a straight-line basis over the period the employee or non-employee director is required to provide service in exchange for the award, which is generally the vesting period. The Company classifies stock-based compensation expense in its consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. The Company bases its estimate of expected volatility on the historical volatility of comparable companies from a representative peer group selected based on industry, financial, and market capitalization data. The Company recognizes forfeitures as they occur. Determining the grant date fair value of options using the Black-Scholes option pricing model requires management to make assumptions and judgments. These estimates involve inherent uncertainties and, if different assumptions had been used, stock-based compensation expense could have been materially different from the amounts recorded.
Income Taxes	Income Taxes Income taxes are accounted for using an asset and liability approach that requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement carrying amount and tax basis of assets and liabilities and are measured using enacted tax rates in effect for the year in which the difference is expected to reverse. The effect of a change in tax rates or tax law on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. A valuation allowance is provided on deferred tax assets if, based upon the available evidence, it is determined to be more-likely-than-not that some portion or all of the deferred tax assets will not be realized. Management regularly reviews the deferred tax assets for recoverability based on historical taxable income, projected taxable income, the expected timing of the reversals of existing temporary differences and tax planning strategies. The Company accounts for uncertain tax positions based on a two-step process of evaluating recognition and measurement criteria. The first step assesses whether the tax position is more-likely-than-not to be sustained upon examination by the taxing authority, including resolution of any appeals or litigation, on the basis of the technical merits of the position. If the tax position meets the more-likely-than-not criteria, the portion of the tax benefit that has a greater than 50% likelihood of being realized upon settlement with the relevant tax authority is recognized in the consolidated financial statements. The Company’s policy is to recognize interest and penalties related to
Recently Adopted and Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements The Company is provided the option to adopt new or revised accounting guidance as an “emerging growth company” under the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”) either (1) within the same periods as those otherwise applicable to public business entities, or (2) within the same time periods as private companies, including early adoption when permissible. With the exception of standards the Company elected to early adopt, when permissible, the Company has elected to adopt new or revised accounting guidance within the same time period as private companies, as indicated below. In May 2014, the Financial Accounting Standards Board ("FASB"), issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (Topic 606) . ASU 2014-09 amends the guidance for revenue recognition to replace numerous industry-specific requirements and converges areas under the Revenue from Contracts with Customers topic with those of the International Financial Reporting Standards. The guidance implements a five-step process for customer contract revenue recognition that focuses on transfer of control, as opposed to transfer of risk and rewards. The amendment also requires enhanced disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows from contracts with customers. Other major provisions include the capitalization and amortization of certain contract costs, ensuring the time value of money is considered in the transaction price, and allowing estimates of variable consideration to be recognized before contingencies are resolved in certain circumstances. Entities were given the option of transitioning to the standard either retrospectively or as a cumulative-effect adjustment as of the date of adoption (“modified retrospective”). The guidance is effective for the Company for the year beginning after December 15, 2018, with early adoption permitted. Since its issuance, the FASB has amended several aspects of the new guidance including provisions that clarify the implementation guidance on principal versus agent considerations in the new revenue recognition standard. The amendments clarify how an entity should identify the unit of accounting (i.e., the specified good or service) for the principal versus agent evaluation and how it should apply the control principle to certain types of arrangements. The Company adopted the new standard on a modified retrospective basis as of January 1, 2019 and there was a net impact of $0.6 million to the Company’s accumulated deficit on the date of adoption. In January 2016, the FASB issued ASU 2016-01, Financial Instruments – Overall (Subtopic 825-10) . ASU 2016-01 requires equity investments (except those accounted for under the equity method, those that result in consolidation of the investee and certain other investments) to be measured at fair value with any changes in fair value recognized in net income (loss). For equity investments that do not have readily determinable fair values and do not qualify for the existing practical expedient in ASC 820, Fair Value Measurements, to estimate fair value using the net asset value per share of the investment, the Company may choose to measure those investments at cost, less any impairment, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. The guidance in ASU 2016-01 is effective for the Company for the year beginning after December 15, 2018. The Company adopted this standard on January 1, 2019. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting , under which entities are permitted to make an accounting policy election to either estimate forfeitures on share-based payment awards, as previously required, or to recognize forfeitures as they occur. The guidance in ASU 2016-09 is effective for the Company for the year beginning after December 15, 2017. The Company adopted this standard on January 1, 2018 and made an accounting policy election to account for forfeitures as they occur. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments , which was intended to reduce diversity in practice in how certain cash receipts and payments are presented and classified in the statement of cash flows. The standard provides guidance in a number of situations including, among others, settlement of zero-coupon bonds, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, and distributions received from equity method investees. The ASU also provides guidance for classifying cash receipts and payments that have aspects of more than one class of cash flows. The guidance in ASU 2016-15 is effective for the Company for the year beginning after December 15, 2018. The Company adopted this standard on a retrospective basis on January 1, 2019. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory , to improve the accounting for income tax consequences of intra-entity transfers of assets other than inventory and to eliminate diversity of practice and a source of complexity in financial reporting. The guidance in ASU 2016-16 is effective for the Company for the year beginning after December 15, 2018. The Company adopted ASU 2016-16 on a modified retrospective basis on January 1, 2019. There was no impact of this standard at the date of adoption. The application of this standard resulted in the recognition of $0.4 million in income tax expense in the consolidated statement of operations for intra-entity transfers occurring during the year ended December 31, 2019. In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business. This ASU provides guidance to evaluate whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. If substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single asset or a group of similar assets, the assets acquired (or disposed of) are not considered a business. The guidance in ASU 2017-01 is effective for the Company for the year beginning after December 15, 2018, with early adoption permitted. The Company early adopted this standard on January 1, 2018. There was no impact of this standard at the date of adoption. The Company applied the new standard to its acquisition of DogBuddy in 2018 and accounted for the transaction as a business acquisition (see Note 3—Business Combinations). In May 2017, the FASB issued ASU 2017-09, Compensation – Stock Compensation (Topic 718)—Scope of Modification Accounting , which provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting. The amendments in this update will be applied prospectively to an award modified on or after the adoption date. The guidance in ASU 2017-09 is effective for the Company for the year beginning after December 15, 2017. The Company adopted this standard on January 1, 2018. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. In June 2018, the FASB issued ASU 2018-07, Compensation-Stock Compensation (Topic 718), Improvements to Nonemployee Share-based Payments. ASU 2018-07 expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The guidance in ASU 2018-07 is effective for the Company for the year beginning after December 15, 2019. Early adoption is permitted, but no earlier than a company’s adoption date of Topic 606. The Company early adopted this standard on January 1, 2019. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) - Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement. ASU 2018-13 removes the disclosure requirement for the amount and reasons for transfers between Level 1 and Level 2 fair value measurements as well as the process for Level 3 fair value measurements. In addition, the ASU adds the disclosure requirements for changes in unrealized gains and losses included in other comprehensive income (loss) for recurring Level 3 fair value measurements held at the end of the reporting period as well as the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The guidance is effective for the Company for the year beginning after December 15, 2019. The Company adopted this standard on January 1, 2020. The adoption of the new standard did not have a material impact on the Company’s consolidated financial statements. Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , as amended, with guidance regarding the accounting for and disclosure of leases. The standard requires lessees to recognize a right-of-use asset and lease liability on its consolidated balances sheet for all leases with a term longer than twelve months. This update also requires lessees and lessors to disclose key information about their leasing transactions. The guidance is effective for the Company for the year beginning after December 15, 2021. Early adoption is permitted. The Company early adopted ASU 2016-02 effective January 1, 2021 which resulted in the recognition of material right-of-use assets and lease liabilities. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, as amended, which amends guidance on reporting credit losses for assets held at amortized cost basis and available-for-sale debt securities from an incurred loss methodology to an expected loss methodology. For assets held at amortized cost basis, the guidance eliminates the probable initial recognition threshold and instead requires an entity to reflect its current estimate of all expected credit losses. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the assets to present the net amount expected to be collected. For available-for-sale debt securities, credit losses are recorded through an allowance for credit losses, rather than a write-down, limited to the amount by which fair value is below amortized cost. Additional disclosures about significant estimates and credit quality are also required. The guidance is effective for the Company for the year beginning after December 15, 2022. The Company is currently assessing the potential impact of adopting ASU 2016-13 on its consolidated financial statements and does not expect the adoption to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Intangible – Goodwill and Other-Internal-Use Software , which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The guidance is effective for the Company for the year beginning after December 15, 2020. Early adoption is permitted. The Company is currently assessing the potential impact of adopting ASU 2018-15 on its consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. This ASU removes certain exceptions to the general principles of Topic 740 and provides clarification and simplification of existing guidance. The guidance is effective for the Company for the year beginning after December 15, 2021. Early adoption is permitted. The Company is currently assessing the potential impact of adopting ASU 2019-12 on its consolidated financial statements. In January 2020, the FASB issued ASU 2020-01, Investments-Equity Securities (Topic 321), Investments-Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815) - Clarifying the Interactions between Topic 321, Topic 323, and Topic 815. This guidance addresses accounting for the transition into and out of the equity method and provides clarification of the interaction of rules for equity securities, the equity method of accounting, and forward contracts and purchase options on certain types of securities. The guidance is effective for the Company for the year beginning after December 15, 2021. The Company is currently assessing the potential impact of adopting ASU 2020-01 on its consolidated financial statements. In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40). The objective of this update is to simplify the accounting for convertible preferred stock by removing the existing guidance in ASC 470-20, “Debt: Debt with Conversion and Other Options,”, that requires entities to account for beneficial conversion features and cash conversion features in equity, separately from the host convertible debt or preferred stock. The guidance in ASC 470-20 applies to convertible instruments for which the embedded conversion features are not required to be bifurcated from the host contract and accounted for as derivatives. In addition, the amendments revise the scope exception from derivative accounting in ASC 815-40 for freestanding financial instruments and embedded features that are both indexed to the issuer’s own stock and classified in stockholders’ equity, by removing certain criteria required for equity classification. These amendments are expected to result in more freestanding financial instruments qualifying for equity classification (and, therefore, not accounted for as derivatives), as well as fewer embedded features requiring separate accounting from the host contract. This amendment also further revises the guidance in ASU 260, “Earnings per Share,” to require entities to calculate diluted earnings per share (EPS) for convertible instruments by using the if-converted method. In addition, entities must presume share settlement for purposes of calculating diluted EPS when an instrument may be settled in cash or shares. The guidance is effective

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Schedule of Property, Plant and Equipment	Property and equipment are stated at cost and are depreciated or amortized using the straight-line method over the estimated useful lives of the assets. Depreciation provisions are based upon the following estimated useful lives: Asset Category Depreciation Period Computers 3 years Furniture and fixtures 5-7 years Leasehold improvements Shorter of estimated useful life of asset or remaining lease term The following table presents the detail of property and equipment, net as follows (in thousands): December 31, 2019 2020 Computers $ 1,534 $ 1,346 Furniture and fixtures 3,913 3,906 Leasehold improvements 13,136 13,660 Internal-use software 23,753 20,850 Total property and equipment 42,336 39,762 Less: Accumulated depreciation and amortization (11,345) (14,839) Total property and equipment, net $ 30,991 $ 24,923 The following table presents the detail of property and equipment, net as follows (in thousands): December 31, September 30, Computers $ 1,346 $ 1,632 Furniture and fixtures 3,906 3,857 Leasehold improvements 13,660 13,663 Internal-use software 20,850 22,081 Total property and equipment 39,762 41,233 Less: Accumulated depreciation and amortization (14,839) (19,281) Total property and equipment, net $ 24,923 $ 21,952

Reverse Recapitalization (Table

Reverse Recapitalization (Tables)	9 Months Ended
	Sep. 30, 2021
Reverse Recapitalization [Abstract]
Schedule of Reverse Recapitalization	The number of shares of Class A common stock issued immediately following the consummation of the Merger at July 30, 2021 was: Number of Shares Common stock of Caravel outstanding prior to the Merger 27,500,000 Less redemption of Caravel shares (14,677,808) Caravel Sponsor Earnout Shares outstanding prior to the Merger 6,875,000 Less forfeiture of Caravel Sponsor Earnout Shares(1) (975,873) Common stock of Caravel (1) 18,721,319 Shares issued in PIPE financing 5,000,000 Shares issued in Sponsor Backstop Subscription Agreement 8,000,000 Shares issued in Assignment Agreement 1,000,000 Merger and PIPE financing shares 32,721,319 Legacy Rover shares (2) 124,477,819 Total 157,199,138 __________ (1) Upon the Merger closing, 3,437,500 Sponsor Earnout Shares vested, 975,873 were forfeited and 2,461,627 Sponsor Earnout Shares remained outstanding and unvested. At Closing, the remaining 2,461,627 Sponsor Earnout Shares were subject to vesting conditions based upon the occurrence of certain triggering events. At the close of trading on September 29, 2021, pursuant to the Business Combination Agreement and the achievement of Trigger Events I and II, 1,969,300 Founder Shares vested.

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Schedule of Purchase Consideration, Tangible and Intangible Assets Acquired	The table below presents components of the purchase consideration, and the tangible and intangible assets acquired, and liabilities assumed, at fair value, in connection with the acquisition (in thousands): Assets Current assets Cash and cash equivalents $ 5,219 Accounts receivable 7 Prepaid expenses and other current assets 163 Total current assets 5,389 Property and equipment 67 Intangible assets 10,850 Goodwill 23,728 Other noncurrent assets 57 Total assets 40,091 Liabilities Current liabilities Accounts payable 28 Accrued expenses and other current liabilities 74 Deferred revenue 109 Pet parent deposits 681 Total current liabilities 892 Deferred tax liability 1,551 Total liabilities 2,443 Total consideration $ 37,648
Schedule of Estimated Useful Lives of the Acquired Intangible Assets	The table below summarizes the estimated useful lives of the acquired intangible assets and the methodologies employed in determining their related estimated fair values (in thousands): Fair Value Estimated Useful Life (years) Pet parent relationships $ 6,600 8 Pet service provider relationships 2,000 3 Technologies 2,200 2 Non-competition agreements 50 1 Total intangible assets $ 10,850
Schedule of Supplemental Pro Forma Financial Information	The following table summarizes certain supplemental pro forma financial information for the year ended December 31, 2018 as if the acquisition of DogBuddy had occurred as of January 1, 2018 (in thousands): Year Ended December 31, 2018 As Reported Pro Forma Revenue $ 71,411 $ 73,261 Net loss (64,677) (69,962) Net loss attributable to common stockholders $ (65,168) $ (70,453)

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Contract Liabilities	The Company’s contract liabilities consist of deferred revenue. The changes in the Company’s contract liabilities were as follows (in thousands): Balance at December 31, 2018 $ 2,585 Revenue recognized (92,063) Bookings and other 91,966 Balance at December 31, 2019 2,488 Revenue recognized (45,585) Bookings and other 43,848 Balance at December 31, 2020 $ 751 The Company’s contract liabilities consist of deferred revenue. The changes in the Company’s contract liabilities were as follows (in thousands): Balance at December 31, 2020 $ 751 Bookings and other 73,900 Revenue recognized (68,648) Balance at September 30, 2021 $ 6,003 Balance at June 30, 2021 $ 8,167 Bookings and other 32,067 Revenue recognized (34,231) Balance at September 30, 2021 $ 6,003

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-sale Securities Reconciliation	The amortized cost and fair value of the available-for-sale investments and unrealized gains and losses were as follows (in thousands): December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Corporate securities and commercial paper $ 25,291 $ 64 — $ 25,355 Asset-backed securities 660 — — 660 Certificates of deposit 10,118 — — 10,118 Total $ 36,069 $ 64 — $ 36,133
Schedule of Contractual Maturity of Available-for-sale Investments	The contractual maturity of the available-for-sale investments were as follows (in thousands): December 31, 2019 Less than 1 year 1 to 5 years More than 5 years Total Corporate securities and commercial paper $ 17,187 $ 8,168 $ — $ 25,355 Asset-backed securities 0 660 0 660 Certificates of deposit 8,120 1,998 0 10,118 Total $ 25,307 $ 10,826 $ — $ 36,133

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis	The following table presents the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2019 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 15,088 $ — $ — $ 15,088 Investments: Commercial paper — 6,032 — 6,032 Corporate securities — 19,323 — 19,323 Asset-backed securities — 660 — 660 Certificate of deposits — 10,118 — 10,118 Total $ 15,088 $ 36,133 $ — $ 51,221 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,854 $ — $ — $ 37,854 Total $ 37,854 $ — $ — $ 37,854 The following table presents the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis (in thousands): December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,854 $ — $ — $ 37,854 Total assets measured at fair value $ 37,854 $ — $ — $ 37,854 September 30, 2021 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 37,859 $ — $ — $ 37,859 Total assets measured at fair value $ 37,859 $ — $ — $ 37,859 Liabilities Earnout liabilities $ — $ — $ 266,390 $ 266,390 Derivative warrant liabilities (Public Warrants) 23,320 — — 23,320 Derivative warrant liabilities (Private Warrants) — — 10,974 10,974 Total liabilities measured at fair value $ 23,320 $ — $ 277,364 $ 300,684
Schedule of Level 3 Financial Liabilities	The following table provides a summary of changes in the estimated fair value of the Company’s Level 3 assets measured on a non-recurring basis (in thousands): Balance at December 31, 2018 $ — Initial investment in DogHero 5,000 Balance at December 31, 2019 5,000 Impairment of DogHero investment $ (2,080) Sale of DogHero investment (2,920) Balance at December 31, 2020 $ — The following table provides a reconciliation of the beginning and ending balances for the level 3 financial liabilities measured at fair value using significant unobservable inputs (in thousands): Earnout Private Warrant Balance at December 31, 2020 $ — $ — Additions during the period 228,082 7,677 Change in fair value 71,318 3,297 Reclassification of earnout liability upon Triggering Events (33,010) — Balance at September 30, 2021 $ 266,390 $ 10,974
Schedule of Fair Value Measurement Inputs and Valuation Techniques	The estimated fair value of the Earnout Shares was determined using a Monte Carlo simulation valuation model using the following assumptions at each valuation date: July 30, September 29, 2021 September 30, 2021 Stock price $ 10.99 $ 13.59 $ 13.59 Risk-free interest rate 1.00 % 1.29 % 1.29 % Expected term (in years) 7.0 6.8 6.8 Expected volatility 57.20 % 56.50 % 56.50 % Dividend yield — % — % — % The estimated fair value of the Private Warrants was determined using a Monte Carlo simulation valuation model using the following assumptions at each valuation date: July 30, September 30, 2021 Stock price $ 10.99 $ 13.59 Risk-free interest rate 0.69 % 0.94 % Expected term (in years) 5.0 4.8 Expected volatility 31.50 % 36.50 % Dividend yield — % — %

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Property, Plant and Equipment	Property and equipment are stated at cost and are depreciated or amortized using the straight-line method over the estimated useful lives of the assets. Depreciation provisions are based upon the following estimated useful lives: Asset Category Depreciation Period Computers 3 years Furniture and fixtures 5-7 years Leasehold improvements Shorter of estimated useful life of asset or remaining lease term The following table presents the detail of property and equipment, net as follows (in thousands): December 31, 2019 2020 Computers $ 1,534 $ 1,346 Furniture and fixtures 3,913 3,906 Leasehold improvements 13,136 13,660 Internal-use software 23,753 20,850 Total property and equipment 42,336 39,762 Less: Accumulated depreciation and amortization (11,345) (14,839) Total property and equipment, net $ 30,991 $ 24,923 The following table presents the detail of property and equipment, net as follows (in thousands): December 31, September 30, Computers $ 1,346 $ 1,632 Furniture and fixtures 3,906 3,857 Leasehold improvements 13,660 13,663 Internal-use software 20,850 22,081 Total property and equipment 39,762 41,233 Less: Accumulated depreciation and amortization (14,839) (19,281) Total property and equipment, net $ 24,923 $ 21,952
Schedule of Accrued Expenses and Other Current Liabilities	The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, 2019 2020 Accrued merchant fees $ 778 $ 172 Income and other tax liabilities 711 185 Accrued legal expenses and open claims 656 382 Lease incentive, current 453 491 Coupon liabilities 352 226 Accrued interest — 259 Accrued professional services 213 872 Series G preferred stock holdback liability 320 — Other current liabilities 1,180 160 Total accrued expenses and other current liabilities $ 4,663 $ 2,747 The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, September 30, Accrued merchant fees $ 172 $ 8 Income and other tax liabilities 185 1,012 Accrued legal expenses and open claims 382 1,017 Lease incentive, current 491 — Accrued interest 259 14 Accrued professional services 872 540 Other current liabilities 386 238 Total accrued expenses and other current liabilities $ 2,747 $ 2,829
Schedule of Accrued Expenses and Other Current Liabilities	The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, 2019 2020 Accrued merchant fees $ 778 $ 172 Income and other tax liabilities 711 185 Accrued legal expenses and open claims 656 382 Lease incentive, current 453 491 Coupon liabilities 352 226 Accrued interest — 259 Accrued professional services 213 872 Series G preferred stock holdback liability 320 — Other current liabilities 1,180 160 Total accrued expenses and other current liabilities $ 4,663 $ 2,747 The following table presents the detail of accrued expenses and other current liabilities as follows (in thousands): December 31, September 30, Accrued merchant fees $ 172 $ 8 Income and other tax liabilities 185 1,012 Accrued legal expenses and open claims 382 1,017 Lease incentive, current 491 — Accrued interest 259 14 Accrued professional services 872 540 Other current liabilities 386 238 Total accrued expenses and other current liabilities $ 2,747 $ 2,829

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	The gross book value and accumulated amortization of intangible assets were as follows (in thousands): December 31, 2019 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (6,364) $ 9,926 Technologies 10,100 (8,525) 1,575 Pet service provider relationships 2,000 (778) 1,222 Tradenames 950 (522) 428 Total $ 29,340 $ (16,189) $ 13,151 December 31, 2020 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (9,117) $ 7,173 Pet service provider relationships 2,000 (1,444) 556 Tradenames 950 (712) 238 Total $ 19,240 $ (11,273) $ 7,967 The weighted average amortization period remaining as of December 31, 2020 for each class of intangible assets were as follows (in years): Pet parent relationships 4.3 Pet service provider relationships 0.8 Tradenames 1.3 The gross book value and accumulated amortization of intangible assets were as follows (in thousands): December 31, 2020 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 $ (9,117) $ 7,173 Pet service provider relationships 2,000 (1,444) 556 Tradenames 950 (712) 238 Total $ 19,240 $ (11,273) $ 7,967 September 30, 2021 Gross Book Accumulated Net Book Pet parent relationships $ 16,290 (11,181) $ 5,109 Pet service provider relationships 2,000 (1,944) 56 Tradenames 950 (855) 95 Total $ 19,240 $ (13,980) $ 5,260 The weighted average amortization period remaining as of September 30, 2021 for each class of intangible assets were as follows (in years): Pet parent relationships 4.2 Pet service provider relationships 0.1 Tradenames 0.5
Schedule of Intangible Assets, Future Amortization Expense	Based on amounts recorded at December 31, 2020 the Company estimates intangible asset amortization expense in each of the years ending December 31 as follows (in thousands): 2021 $ 3,499 2022 1,347 2023 814 2024 814 2025 814 Thereafter 679 Total $ 7,967 Based on amounts recorded at September 30, 2021, the Company estimates intangible asset amortization expense in each of the years ending December 31 as follows (in thousands): Remainder of 2021 $ 792 2022 1,347 2023 814 2024 814 2025 814 Thereafter 679 Total $ 5,260
Schedule of Goodwill	The following table summarizes the changes in the carrying amount of goodwill (in thousands): Balance at December 31, 2018 $ 34,811 Measurement period adjustment – DogBuddy (see Note 3—Business Combinations) (1,652) Balance at December 31, 2019 $ 33,159

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Future Minimum Payments of Principal Outstanding Debt	Future minimum payments of principal on the Company’s outstanding debt borrowings were as follows for the years ending December 31 (in thousands): Year Ending December 31 Amounts 2021 4,505 2022 33,619 2023 — 2024 — 2025 — Total principal amount 38,124 Unamortized discount (598) Carrying value of debt 37,526

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Lease Cost and Other Information	The components of lease cost were as follows (in thousands): Three Months Ended Nine Months Ended Operating lease cost $ 1,046 $ 3,011 Short-term lease cost 19 138 Sublease income (304) (649) Total lease cost $ 761 $ 2,500 Other information related to leases was as follows (in thousands): Nine Months Ended Cash paid for operating lease liabilities $ 3,159 Lease term and discount rate were as follows: As of September 30, 2021 Weighted-average discount rate 7.12 % Weighted-average remaining lease term (years) 7.88
Schedule of Operating Lease Maturity	Maturities of lease liabilities were as follows as of September 30, 2021 (in thousands): Year Ending December 31 Amounts Remainder of 2021 $ 1,156 2022 4,669 2023 4,700 2024 4,563 2025 4,693 Thereafter 18,209 Total lease payments 37,990 Less: imputed interest (9,331) Present value of lease liabilities 28,659 Less: current portion of lease liabilities (2,726) Total lease liabilities, noncurrent $ 25,933
Schedule of Lease Maturity Under ASC 840	The minimum future lease obligations in each of the years ending December 31 are as follows (in thousands): Year Ending December 31 Amounts 2021 $ 4,356 2022 4,303 2023 4,433 2024 4,563 2025 4,693 Thereafter 18,209 Total $ 40,557 Under ASC Topic 840, Leases , contractual commitments related to operating leases were as follows as of December 31, 2020 (in thousands): Year Ending December 31 Amounts 2021 $ 4,356 2022 4,303 2023 4,433 2024 4,563 2025 4,693 Thereafter 18,209 Total $ 40,557

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Temporary Equity	The Company had outstanding redeemable convertible preferred stock as follows (in thousands, except per share amounts): December 31, 2019 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0080 6,981 7,000 Series E 11,021 11,439 3.4968 39,906 40,000 Series F 11,772 12,218 5.3200 64,833 65,000 Series G 18,537 19,112 7.2539 137,291 138,636 Total 87,611 90,805 $ 290,365 $ 294,740 December 31, 2020 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $ 7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802 Shares Authorized Shares Issued and Outstanding Issuance Price Per Share Net Carrying Value Liquidation Preference Series A 8,710 9,040 $0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802
Schedule of Common Stock Reserved for Future Issuance	The Company had reserved shares of Class A common stock for issuance, on an as-converted basis, as follows (in thousands): December 31, September 30, Conversion of redeemable convertible preferred stock 90,814 — Common stock warrants outstanding 1,118 — Private Warrants — 2,574 Public Warrants — 5,500 Rover Earnout Shares — 19,734 Sponsor Earnout Shares — 492 Stock options issued and outstanding 24,700 19,955 Shares available for future equity grants 5,199 17,258 Total 121,831 65,513

Common Stock (Tables)

Common Stock (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Summary of Common Stock Shares Reserved for Future Issuance	The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows (in thousands): December 31 2019 2020 Conversion of redeemable convertible preferred stock 90,805 90,814 Common stock warrants outstanding 790 1,118 Stock options issued and outstanding 24,911 24,700 Shares available for future option grants 4,094 5,199 Total 120,600 121,831

Redeemable Convertible Prefer_2

Redeemable Convertible Preferred Stock (Tables)	9 Months Ended
	Sep. 30, 2021
Temporary Equity Disclosure [Abstract]
Temporary Equity	The Company had outstanding redeemable convertible preferred stock as follows (in thousands, except per share amounts): December 31, 2019 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0080 6,981 7,000 Series E 11,021 11,439 3.4968 39,906 40,000 Series F 11,772 12,218 5.3200 64,833 65,000 Series G 18,537 19,112 7.2539 137,291 138,636 Total 87,611 90,805 $ 290,365 $ 294,740 December 31, 2020 Shares Shares Issuance Net Liquidation Series A 8,710 9,040 $ 0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $ 7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802 Shares Authorized Shares Issued and Outstanding Issuance Price Per Share Net Carrying Value Liquidation Preference Series A 8,710 9,040 $0.4478 $ 3,325 $ 4,048 Series B 14,104 14,639 0.6528 9,397 9,556 Series C 12,431 12,903 1.1238 14,596 14,500 Series D 7,677 7,968 2.0080 14,036 16,000 Series D-1 3,359 3,486 2.0078 6,981 7,000 Series E 11,021 11,439 3.4969 39,906 40,000 Series F 11,772 12,218 5.3199 64,833 65,000 Series G 18,537 19,121 $7.2536 137,353 138,698 Total 87,611 90,814 $ 290,427 $ 294,802

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of stock option activity	A summary of stock option activity is as follows (in thousands, except per share amounts and years): Options Available for Grant Number of Options Outstanding Weighted- Average Exercise Price Per Share Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Balances as of December 31, 2018 2,190 20,578 $ 1.27 7.4 Options authorized 7,203 — Options granted (6,897) 6,897 2.77 Options exercised — (966) 0.82 Options cancelled and forfeited 1,598 (1,598) 2.09 Balances as of December 31, 2019 4,094 24,911 $ 1.65 7.1 $ 34,776 Options authorized 1,801 — Options granted (1) (11,258) 11,258 2.08 Options exercised — (907) 0.85 Options cancelled and forfeited (1) 10,562 (10,562) 2.67 Balances as of December 31, 2020 5,199 24,700 $ 1.45 6.4 $ 83,570 'Options vested and exercisable –December 31, 2020 17,262 $ 1.20 5.5 $ 62,719 ________________ (1) Includes options that were canceled and re-granted as part of the option repricing modification, as further discussed below. A summary of stock option activity is as follows (in thousands, except per share amounts and years): Options Number of Weighted- Weighted- Aggregate Balances as of December 31, 2020 4,330 20,574 $ 1.74 6.4 $ 83,570 Retroactive application of reverse recapitalization 869 4,126 Balance as of December 31, 2020, as converted 5,199 24,700 $ 1.45 6.4 $ 83,570 Options authorized 17,200 Options exercised — (2,881) 1.08 Options cancelled in connection with termination of 2011 Plan (7,005) Options cancelled and forfeited 1,864 (1,864) 2.68 Balances as of September 30, 2021 17,258 19,955 $ 1.53 6.1 $ 240,692 Options vested and exercisable – September 30, 2021 15,369 $ 1.36 5.5 $ 187,904
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following table presents the range of assumptions used to estimate the fair value of options granted during the periods presented: Year Ended December 31 2018 2019 2020 Risk-free interest rate 2.34% - 3.08% 1.38% - 2.60% 0.24% - 1.43% Expected term (years) 3.09 - 6.97 4.51 - 6.75 3.99 - 6.80 Volatility 44.5% - 50.6% 44.5% - 46.3% 49.0% - 54.8% Dividend yield — % — % — %
Schedule of stock-based compensation expense	The following table summarizes stock-based compensation expense recorded in each component of costs and expenses in the Company’s consolidated statements of operations for the presented periods (in thousands): Year Ended December 31 2018 2019 2020 Operations and support $ 206 $ 277 $ 299 Marketing 181 301 397 Product development 2,391 1,486 1,873 General and administrative 3,904 2,003 2,972 Total stock-based compensation expense $ 6,682 $ 4,067 $ 5,541 The following table summarizes stock-based compensation expense recorded in each component of operating expenses in the Company’s condensed consolidated statements of operations for the presented periods (in thousands): Three Months Ended September 30, Nine Months Ended 2020 2021 2020 2021 Operations and support $ 100 $ 43 $ 261 $ 144 Marketing 123 71 348 238 Product development 510 287 1,459 981 General and administrative 1,056 593 2,200 1,779 Total stock-based compensation expense $ 1,789 $ 994 $ 4,268 $ 3,142

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Schedule of Components of Loss before Income Taxes	The following table presents the components of loss before income taxes (in thousands): Year Ended December 31, 2018 2019 2020 U.S. (63,467) (48,650) (56,758) Foreign (1,479) (3,532) (821) Total (64,946) (52,182) (57,579)
Schedule of Components of Provision for Benefit from Income Taxes	The following table presents the components of the (provision for) benefit from income taxes (in thousands): Year Ended December 31, 2018 2019 2020 Current tax expense: U.S. Federal $ — $ — $ — State — (29) (5) Foreign (9) (91) (204) Total current (9) (120) (209) Deferred tax expense: U.S. Federal — — — State — — — Foreign 278 588 303 Total deferred tax benefit 278 588 303 Total income tax benefit $ 269 $ 468 $ 94
Schedule of Reconciliation of Statutory Federal Rate to the Company's Effective Tax rate	The following table presents a reconciliation of the statutory federal rate to the Company’s effective tax rate: Year Ended December 31, 2018 2019 2020 Federal income taxes at statutory rate 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 1.8 1.7 1.6 Tax credits 1.3 1.6 0.2 Equity compensation (1.1) (1.0) (0.9) Change in valuation allowance (21.3) (20.6) (20.9) Other, net (1.3) (1.8) (0.8) Effective income tax rate 0.4 % 0.9 % 0.2 %
Schedule of Deferred Tax Assets and Liabilities	The following table presents the significant components of the Company’s deferred tax assets and liabilities (in thousands): December 31, 2019 2020 Deferred tax assets: Net operating loss carryforward $ 46,810 $ 55,649 Tax credit carryforward 2,199 2,298 Reserves and accruals 1,030 909 Stock based compensation 498 1,011 Property, plant and equipment — 214 Other 21 898 Total deferred tax assets 50,558 60,979 Less: Deferred tax assets valuation allowance (45,180) (57,225) Total deferred tax assets, net of valuation allowance 5,378 3,754 Deferred tax liabilities: Capitalized internal-use software costs (3,223) (2,477) Intangibles (1,076) (42) Property, plant and equipment (153) — Total deferred tax liabilities (4,452) (2,519) Net deferred tax assets $ 926 $ 1,235
Summary of Rollforward of Valuation Allowance	The following table presents a rollforward of the valuation allowance (in thousands): Year Ended December 31, 2018 2019 2020 Balance at beginning of period $ 20,620 $ 34,435 $ 45,180 Increase in valuation allowance 13,815 10,745 12,045 Balance at end of period $ 34,435 $ 45,180 $ 57,225
Schedule of Gross Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2018 2019 2020 Beginning of period $ 218 $ 383 $ 550 Current year tax position increases 165 167 24 End of period $ 383 $ 550 $ 574

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Computation of Basic and Diluted Net Loss per Share Attributable to Common Stockholders	The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except per share amounts): Year Ended December 31, 2018 2019 2020 Numerator: Net loss $ (64,677) $ (51,714) $ (57,485) Deemed dividend to preferred stockholders (491) — — Net loss attributable to common stockholders $ (65,168) $ (51,714) $ (57,485) Denominator: Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, basic and diluted 27,150 29,138 29,896 Net loss per share attributable to common stockholders, basic and diluted $ (2.40) $ (1.77) $ (1.92) The following table sets forth the computation of basic and diluted net loss per common share attributable to common stockholders (in thousands, except share and per share data): Three Months Ended September 30, Nine Months Ended 2020 2021 2020 2021 Numerator: Net loss $ (10,359) $ (84,536) $ (48,983) $ (97,933) Denominator: Weighted-average shares used to compute basic and diluted net loss per share 30,008 116,597 29,834 59,825 Net loss per common share - basic and diluted $ (0.35) $ (0.73) $ (1.64) $ (1.64)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive shares were not included in the calculation of diluted shares outstanding for the periods presented as the effect would have been anti-dilutive (in thousands): Year Ended December 31, 2018 2019 2020 Redeemable convertible preferred stock 90,305 90,805 90,814 Outstanding stock options 20,578 24,911 24,700 Outstanding common stock warrants 674 790 1,118 Total 111,557 116,506 116,632 The following potentially dilutive shares were not included in the calculation of diluted shares outstanding for the periods presented as the effect would have been anti-dilutive (in thousands): September 30, 2020 2021 Redeemable convertible preferred stock 90,814 — Outstanding stock options 25,481 19,955 Outstanding common stock warrants 1,118 — Private Warrants — 2,574 Public Warrants — 5,500 Sponsor Earnout Shares — 492 Total 117,413 28,521

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Charges	The following table summarizes restructuring charges recorded in each component of costs and expenses in the Company’s consolidated statements of operations (in thousands): December 31, 2020 Operations and support $ 796 Marketing 593 Product development 1,743 General and administrative 631 Total restructuring charges $ 3,763 Three Months Ended Nine Months Ended Operations and support $ 174 $ 795 Marketing 84 592 Product development 138 1,741 General and administrative 116 623 Total restructuring charges $ 512 $ 3,751

Organization and Description _2

Organization and Description of Business (Details)	Jul. 30, 2021USD ($)$ / sharesshares	Feb. 28, 2021USD ($)$ / sharesshares	Apr. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Sep. 30, 2021USD ($)shares	Sep. 30, 2021USD ($)shares	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)shares	Dec. 31, 2019USD ($)shares	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
Proceeds from reverse recapitalization transaction, gross	$ 268,300,000
Cash proceeds from reverse capitalization transaction	$ 128,300,000
Sale of stock, price per share (in dollars per share) | $ / shares		$ 10
Private investment in public entity		$ 50,000,000
Recapitalization exchange ratio	1.0379							1.0379
Recapitalization adjusted exchange ratio	1.2006
Redeemable convertible preferred stock, authorized (in shares) | shares	87,611,000							87,611,000	87,611,000
Common stock, shares authorized (in shares) | shares					990,000,000	990,000,000		144,250,000	144,250,000
Percent of positions eliminated (in percentage)			50.00%
Proceeds from borrowing on credit facilities						$ 0	$ 64,282,000	$ 64,563,000	$ 0	$ 0
Loan received from Small Business Administration's Paycheck Protection Program			$ 8,100,000
Debt outstanding					$ 0	0		38,124,000
Proceeds from the merger	$ 235,600,000
Transaction costs					(32,700,000)
Accumulated deficit					$ 354,210,000	$ 354,210,000		$ 256,277,000	$ 198,792,000
Issuance of Class B common stock to Sponsor (in shares) | shares		5,000,000
Legacy Rover
Debt Instrument [Line Items]
Common stock, shares authorized (in shares) | shares	144,250,000
Private Placement
Debt Instrument [Line Items]
Number of shares purchased by investors (in shares) | shares	5,000,000
Sale of stock, price per share (in dollars per share) | $ / shares	$ 10
Aggregate purchase price	$ 50,000,000
Private investment in public entity	$ 50,000,000
Sale of stock, adjusted price per share (in dollars per share) | $ / shares	$ 10.379
Issuance of Class B common stock to Sponsor (in shares) | shares	5,000,000
Sponsor Backstop Subscription Agreement
Debt Instrument [Line Items]
Issuance of Class B common stock to Sponsor (in shares) | shares	8,000,000
Sponsor Backstop Subscription Agreement | True Wind Capital II, L.P. And True Wind Capital II-A, L.P.
Debt Instrument [Line Items]
Number of shares purchased by investors (in shares) | shares	9,000,000
Sale of stock, price per share (in dollars per share) | $ / shares	$ 10
Private investment in public entity	$ 90,000,000
Variable Rate Revolving Line Of Credit | Line of Credit
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities				$ 11,400,000
Variable Rate Growth Capital Advance Components | Line of Credit
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities				15,000,000
Subordinated Credit Facility | Line of Credit
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities				$ 30,000,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Apr. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Mar. 31, 2021segment	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)segment	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jun. 30, 2021	Jan. 01, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | segment			1		1
Number of reportable segments | segment			1		1
Accounts receivable, net		$ 7,924,000			$ 7,924,000		$ 2,992,000	$ 2,473,000
Capitalized software development costs					4,600,000	$ 5,200,000	7,000,000	11,900,000	$ 6,200,000
Internal-use software amortization	$ 2,600,000	1,700,000		$ 1,800,000	5,200,000	5,600,000	7,200,000	5,200,000	2,500,000
Interest and penalties accrued							0	0	0
Advertising expense		4,700,000		800,000	8,800,000	7,200,000	8,100,000	37,900,000	47,600,000
Accumulated deficit		(354,210,000)			(354,210,000)		(256,277,000)	(198,792,000)
Income tax expense		$ 36,000		$ (70,000)	$ (280,000)	$ (122,000)	$ (94,000)	(468,000)	$ (269,000)
Internal-use software
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful lives							3 years
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit											$ 600,000
Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax expense								$ 400,000
ASU 2020-06
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]										true
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]										true

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Property and Equipment Net (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Computers
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives		5 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives		7 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated useful lives	Shorter of estimated useful life of asset or remaining lease term

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Earnout Liabilities (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 30, 2021	Sep. 30, 2021	Sep. 29, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Aggregate fair value of Earnout Shares	$ 228,100	$ 266,390		$ 0
Earnout Liabilities | Expected term (in years)
Class of Stock [Line Items]
Earnout liabilities, earnout period	7 years	6 years 9 months 18 days	6 years 9 months 18 days
Rover Earnout Shares
Class of Stock [Line Items]
Earnout shares (in shares)	19,734,183	19,734,000
Aggregate fair value of Earnout Shares		$ 266,400
Rover Earnout Shares | Derivative Instrument, Period, One
Class of Stock [Line Items]
Earnout shares (in shares)	8,770,748
Earnout period, stock price trigger (in dollars per share)	$ 12	$ 12
Earnout period, threshold trading days	20 days
Earnout period, threshold trading day period	30 days
Rover Earnout Shares | Derivative Instrument, Period, Two
Class of Stock [Line Items]
Earnout shares (in shares)	8,770,748
Earnout period, stock price trigger (in dollars per share)	$ 14	$ 14
Earnout period, threshold trading days	20 days
Earnout period, threshold trading day period	30 days
Rover Earnout Shares | Derivative Instrument, Period, Three
Class of Stock [Line Items]
Earnout shares (in shares)		2,192,687
Earnout period, stock price trigger (in dollars per share)	$ 16	$ 16
Earnout period, threshold trading days	20 days
Earnout period, threshold trading day period	30 days
Aggregate fair value of Earnout Shares		$ 28,000
Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout shares (in shares)	2,461,627	492,000
Aggregate fair value of Earnout Shares			$ 33,000
Sponsor Earnout Shares | Derivative Instrument, Period, One
Class of Stock [Line Items]
Earnout shares (in shares)	984,651
Earnout period, stock price trigger (in dollars per share)	$ 12
Sponsor Earnout Shares | Derivative Instrument, Period, Two
Class of Stock [Line Items]
Earnout shares (in shares)	984,651
Earnout period, stock price trigger (in dollars per share)	$ 14
Sponsor Earnout Shares | Derivative Instrument, Period, Three
Class of Stock [Line Items]
Earnout shares (in shares)	492,325
Earnout period, stock price trigger (in dollars per share)			$ 16
Aggregate fair value of Earnout Shares			$ 6,300

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Derivative Warrant Liabilities (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 30, 2021	Dec. 31, 2020	Sep. 30, 2021	Jul. 29, 2021	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)		1,118,000	8,074,164		790,000
Number of shares called by each warrant (in shares)	1		1
Exercise price of warrant (in dollars per share)	$ 11.50		$ 11.50
Warrants exercisable, period after merger completion			30 days
Warrants exercisable, period after initial public offering		12 months
Period which warrants or rights are exercisable	5 years
Tender or exchange offer, acceptance threshold percent of outstanding shares	50.00%
Derivative warrant liabilities	$ 22,000	$ 0	$ 34,294
Private Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	2,574,164		2,574,000	5,166,667
Public Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	5,500,000		5,500,000
Exercise price of warrant (in dollars per share)			$ 11.50

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Marketing (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Advertising expense	$ 4.7	$ 0.8	$ 8.8	$ 7.2	$ 8.1	$ 37.9	$ 47.6

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 01, 2021	Dec. 31, 2020	Sep. 30, 2020
Accounting Policies [Abstract]
Operating lease right-of-use assets	$ 22,080	$ 22,800	$ 0
Present value of lease liabilities		$ 29,600		$ 28,659
Deferred rent, net of current portion, derecognized			2,200
Lease incentives, derecognized			$ 4,600

Reverse Recapitalization - Narr

Reverse Recapitalization - Narrative (Details)	Jul. 30, 2021USD ($)$ / sharesshares	Feb. 28, 2021USD ($)$ / sharesshares	Sep. 30, 2021USD ($)	Sep. 30, 2021USD ($)	Dec. 31, 2020
Schedule Of Reverse Recapitalization [Line Items]
Proceeds from reverse recapitalization transaction, gross	$ 268,300,000
Cash proceeds from reverse capitalization transaction	$ 128,300,000
Private investment in public entity		$ 50,000,000
Shares issued in PIPE financing (in shares) | shares		5,000,000
Sale of stock, price per share (in dollars per share) | $ / shares		$ 10
Reverse recapitalization transaction, net of costs and acquired liabilities				$ 213,459,000
Shares issued in agreement (in shares) | shares	32,721,319
Recapitalization exchange ratio	1.0379				1.0379
Recapitalization adjusted exchange ratio	1.2006
Transaction costs			$ (32,700,000)
Additional paid-in capital, transaction fees	$ 14,500,000
Reverse recapitalization, liabilities assumed	18,200,000
Private Placement
Schedule Of Reverse Recapitalization [Line Items]
Private investment in public entity	$ 50,000,000
Number of shares purchased by investors (in shares) | shares	5,000,000
Sale of stock, adjusted price per share (in dollars per share) | $ / shares	$ 10.379
Shares issued in PIPE financing (in shares) | shares	5,000,000
Sale of stock, price per share (in dollars per share) | $ / shares	$ 10
Sponsor Backstop Subscription Agreement
Schedule Of Reverse Recapitalization [Line Items]
Shares issued in PIPE financing (in shares) | shares	8,000,000
Assignment Agreement
Schedule Of Reverse Recapitalization [Line Items]
Shares issued in PIPE financing (in shares) | shares	1,000,000
True Wind Capital II, L.P. And True Wind Capital II-A, L.P. | Sponsor Backstop Subscription Agreement
Schedule Of Reverse Recapitalization [Line Items]
Private investment in public entity	$ 90,000,000
Number of shares purchased by investors (in shares) | shares	9,000,000
Sale of stock, price per share (in dollars per share) | $ / shares	$ 10
Legacy Rover
Schedule Of Reverse Recapitalization [Line Items]
Cash payment to stockholders, reverse recapitalization			$ 0

Reverse Recapitalization - Sche

Reverse Recapitalization - Schedule of Recapitalization (Details)

Jul. 30, 2021shares

Feb. 28, 2021shares

Sep. 30, 2021shares

Jul. 29, 2021shares

Jun. 30, 2021shares

[1]

Mar. 31, 2021shares

[1]

Dec. 31, 2020shares

Sep. 30, 2020shares

Jun. 30, 2020shares

Mar. 31, 2020shares

Dec. 31, 2019shares

Dec. 31, 2018shares

[2]

Dec. 31, 2017shares

[2]

Reverse Recapitalization [Line Items]

Common stock, shares outstanding (in shares)

157,199,138

157,593,000

32,434,987

30,398,000

29,614,000

Shares issued in PIPE financing (in shares)

5,000,000

Shares issued in agreement (in shares)

32,721,319

Legacy Rover shares (in shares)

124,477,819

Convertible preferred stock, shares outstanding (in shares)

0

[1]

87,496,938

90,814,000

90,814,000

90,814,000

[1]

90,814,000

90,814,000

90,814,000

90,805,000

[2]

90,305,000

71,692,000

Recapitalization exchange ratio

1.0379

1.0379

Private Placement

Reverse Recapitalization [Line Items]

Shares issued in PIPE financing (in shares)

5,000,000

Sponsor Backstop Subscription Agreement

Reverse Recapitalization [Line Items]

Shares issued in PIPE financing (in shares)

8,000,000

Assignment Agreement

Reverse Recapitalization [Line Items]

Shares issued in PIPE financing (in shares)

1,000,000

Founder Shares

Reverse Recapitalization [Line Items]

Shares vested (in shares)

1,969,300

Caravel

Reverse Recapitalization [Line Items]

Common stock, shares outstanding (in shares)

27,500,000

Less redemption of Caravel shares (in shares)

(14,677,808)

Earnout shares (in shares)

6,875,000

Less forfeiture of Caravel Sponsor Earnout Shares (in shares)

(975,873)

Caravel | Common Shareholders

Reverse Recapitalization [Line Items]

Common stock of Caravel (in shares)

18,721,319

Caravel | Sponsor Members

Reverse Recapitalization [Line Items]

Earnout shares (in shares)

2,461,627

Less forfeiture of Caravel Sponsor Earnout Shares (in shares)

(975,873)

Shares vested (in shares)

3,437,500

[1]

The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

[2]

The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Business Combinations - Additio

Business Combinations - Additional Information (Details) - USD ($) $ in Thousands	Oct. 31, 2018	Feb. 29, 2020	Nov. 30, 2019	May 31, 2017	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)		9,000
Revenue															$ 71,411
Net loss					$ (84,536)	$ (2,806)	$ (10,591)	$ (10,359)	$ (18,079)	$ (20,545)	$ (97,933)	$ (48,983)	$ (57,485)	$ (51,714)	(64,677)
Series G Preferred Stock
Business Acquisition [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)			500,000
DogBuddy
Business Acquisition [Line Items]
Number of shares, acquired		100,000
Payments of stock issuance costs	$ 19,400
Business combination, consideration transferred	$ 37,600
Business combination, fair value														3,600
Holdback liabilities														300
Acquisition related costs															1,000
Business combination intangible assets defensive assets															2,200
Revenue															300
Net loss															(1,000)
Defrred taxes business combination														$ 1,700
Transaction cost															1,500
Increae in amortization expense															$ 2,200
DogBuddy | Notes
Business Acquisition [Line Items]
Debt instrument, principal				$ 3,000
Debt instrument, percentage of principal amount redeemed				4.00%
DogBuddy | Series G Redeemable Convertible Peferred Stock
Business Acquisition [Line Items]
Number of shares, acquired	1,900,000
Business combination, fair value	$ 3,900
DogBuddy | Series G Preferred Stock
Business Acquisition [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)	539,000		500,000
Business combination, fair value	$ 10,000
Shares issued during holdback		9,000
Shares retained during holdback		30,000
Common Stock | DogBuddy
Business Acquisition [Line Items]
Number of shares, acquired	1,400,000		3,600,000
Additional shares converted	67,000

Business Combinations - Schedul

Business Combinations - Schedule of Purchase Consideration, and the Tangible and Intangible Assets Acquired, and Liabilities Assumed (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 31, 2018
Current assets
Goodwill	$ 33,159,000	$ 33,159,000	$ 33,159,000	$ 34,811,000
DogBuddy
Current assets
Cash and cash equivalents					$ 5,219,000
Accounts receivable					7,000
Prepaid expenses and other current assets					163,000
Total current assets					5,389,000
Property and equipment					67,000
Intangible assets					10,850,000
Goodwill					23,728,000
Other noncurrent assets					57,000
Total assets					40,091,000
Current liabilities
Accounts payable					28,000
Accrued expenses and other current liabilities					74,000
Deferred revenue					109,000
Pet parent deposits					681,000
Total current liabilities					892,000
Deferred tax liability					1,551,000
Total liabilities					2,443,000
Total consideration					$ 37,648,000

Business Combinations - Sched_2

Business Combinations - Schedule of Purchase Consideration, Tangible and Intangible Assets Acquired (Details) $ in Thousands	Oct. 31, 2018USD ($)
Business Acquisition [Line Items]
Fair Value	$ 10,850
Pet parent relationships
Business Acquisition [Line Items]
Fair Value	$ 6,600
Estimated Useful	8 years
Pet service provider relationships
Business Acquisition [Line Items]
Fair Value	$ 2,000
Estimated Useful	3 years
Technologies
Business Acquisition [Line Items]
Fair Value	$ 2,200
Estimated Useful	2 years
Non-competition agreements
Business Acquisition [Line Items]
Fair Value	$ 50
Estimated Useful	1 year

Business Combinations - Sched_3

Business Combinations - Schedule of Supplemental Pro Forma Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
As Reported
Revenue											$ 71,411
Net loss	$ (84,536)	$ (2,806)	$ (10,591)	$ (10,359)	$ (18,079)	$ (20,545)	$ (97,933)	$ (48,983)	$ (57,485)	$ (51,714)	(64,677)
Net loss attributable to common stockholders									$ (57,485)	$ (51,714)	(65,168)
Pro Forma
Revenue											73,261
Net loss											(69,962)
Net loss attributable to common stockholders											$ (70,453)

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Contract with Customer, Liability [Roll Forward]
Beginning Balance	$ 8,167	$ 751	$ 2,488	$ 2,585
Bookings and other	32,067	73,900	43,848	91,966
Revenue recognized	(34,231)	(68,648)	(45,585)	(92,063)
Ending Balance	$ 6,003	$ 6,003	$ 751	$ 2,488

Investments - Schedule of Amort

Investments - Schedule of Amortized Cost and Fair Value of Available-for-sale Investments and Unrealized Gains and Losses (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Amortized Cost		$ 36,069,000
Gross Unrealized Gains		64,000
Gross Unrealized Losses		0
Fair Value	$ 0	36,133,000
Corporate Securities and Commercial Paper
Schedule Of Investments [Line Items]
Amortized Cost		25,291,000
Gross Unrealized Gains		64,000
Gross Unrealized Losses		0
Fair Value		25,355,000
Asset-backed securities
Schedule Of Investments [Line Items]
Amortized Cost		660,000
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		660,000
Certificate of deposits
Schedule Of Investments [Line Items]
Amortized Cost		10,118,000
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		$ 10,118,000

Investments - Additional Inform

Investments - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended	12 Months Ended
	Nov. 30, 2020	Jul. 31, 2020	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Investments [Line Items]
Fair Value				$ 0	$ 36,133,000
Other-than-temporary impairments recognized in accumulated other comprehensive income				$ 0	$ 0	$ 0
Period for purchase of remaining equity			2 years
DogHero Ltd.
Schedule Of Investments [Line Items]
Business combination, consideration transferred		$ 3,000,000
Business combination, impairment loss		2,000,000
Reducing carrying amount of investment		$ 3,000,000
Sale of investment and call option	$ 2,900,000
Additional impairment loss during disposal of investment and related carrying value	$ 100,000
DogHero Ltd. | Online Marketplace for Pet Service | South America
Schedule Of Investments [Line Items]
Long-term investments			$ 5,000,000
Series C Preference Shares | DogHero Ltd.
Schedule Of Investments [Line Items]
Purchase of shares regarding equity method investments			$ 3,400,000
Percentage of fully diluted outstanding equity regarding equity method investments			17.00%

Investments - Schedule of Contr

Investments - Schedule of Contractual Maturity of Available-for-sale Investments (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Less than 1 year		$ 25,307,000
1 to 5 years		10,826,000
More than 5 years		0
Total	$ 0	36,133,000
Corporate Securities and Commercial Paper
Schedule Of Investments [Line Items]
Less than 1 year		17,187,000
1 to 5 years		8,168,000
More than 5 years		0
Total		25,355,000
Asset-backed securities
Schedule Of Investments [Line Items]
Less than 1 year		0
1 to 5 years		660,000
More than 5 years		0
Total		660,000
Certificate of deposits
Schedule Of Investments [Line Items]
Less than 1 year		8,120,000
1 to 5 years		1,998,000
More than 5 years		0
Total		$ 10,118,000

Fair Value - Assets and Liabili

Fair Value - Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jul. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Liabilities
Derivative warrant liabilities	$ 34,294	$ 22,000	$ 0
Private Warrants
Liabilities
Derivative warrant liabilities	7,700
Fair Value, Recurring
Assets
Total assets measured at fair value	37,859		37,854	$ 51,221
Liabilities
Earnout liabilities	266,390
Total liabilities measured at fair value	300,684
Fair Value, Recurring | Public Warrants
Liabilities
Derivative warrant liabilities	23,320
Fair Value, Recurring | Private Warrants
Liabilities
Derivative warrant liabilities	10,974
Fair Value, Recurring | Money market fund
Assets
Money market fund	37,859		37,854	15,088
Fair Value, Recurring | Level 1
Assets
Total assets measured at fair value	37,859		37,854	15,088
Liabilities
Earnout liabilities	0
Total liabilities measured at fair value	23,320
Fair Value, Recurring | Level 1 | Public Warrants
Liabilities
Derivative warrant liabilities	23,320
Fair Value, Recurring | Level 1 | Private Warrants
Liabilities
Derivative warrant liabilities	0
Fair Value, Recurring | Level 1 | Money market fund
Assets
Money market fund	37,859		37,854	15,088
Fair Value, Recurring | Level 2
Assets
Total assets measured at fair value	0		0	36,133
Liabilities
Earnout liabilities	0
Total liabilities measured at fair value	0
Fair Value, Recurring | Level 2 | Public Warrants
Liabilities
Derivative warrant liabilities	0
Fair Value, Recurring | Level 2 | Private Warrants
Liabilities
Derivative warrant liabilities	0
Fair Value, Recurring | Level 2 | Money market fund
Assets
Money market fund	0		0	0
Fair Value, Recurring | Level 3
Assets
Total assets measured at fair value	0		0	0
Liabilities
Earnout liabilities	266,390
Total liabilities measured at fair value	277,364
Fair Value, Recurring | Level 3 | Public Warrants
Liabilities
Derivative warrant liabilities	0
Fair Value, Recurring | Level 3 | Private Warrants
Liabilities
Derivative warrant liabilities	10,974
Fair Value, Recurring | Level 3 | Money market fund
Assets
Money market fund	$ 0		$ 0	0
Commercial paper
Assets
Investments				6,032
Commercial paper | Level 1
Assets
Investments				0
Commercial paper | Level 2
Assets
Investments				6,032
Commercial paper | Level 3
Assets
Investments				0
Corporate securities
Assets
Investments				19,323
Corporate securities | Level 1
Assets
Investments				0
Corporate securities | Level 2
Assets
Investments				19,323
Corporate securities | Level 3
Assets
Investments				0
Asset-backed securities
Assets
Investments				660
Asset-backed securities | Level 1
Assets
Investments				0
Asset-backed securities | Level 2
Assets
Investments				660
Asset-backed securities | Level 3
Assets
Investments				0
Certificate of deposits
Assets
Investments				10,118
Certificate of deposits | Level 1
Assets
Investments				0
Certificate of deposits | Level 2
Assets
Investments				10,118
Certificate of deposits | Level 3
Assets
Investments				$ 0

Fair Value - Level 3 Financial

Fair Value - Level 3 Financial Liabilities (Details) - Level 3 - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	$ 5,000	$ 0
Initial investment in DogHero			5,000
Impairment of DogHero investment		(2,080)
Sale of DogHero investment		(2,920)
Ending balance		0	$ 5,000
Earnout Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0
Additions during the period	228,082
Change in fair value	71,318
Reclassification of earnout liability upon Triggering Events	(33,010)
Ending balance	266,390	0
Fair Value, Recurring | Private Warrant Derivative Liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0
Additions during the period	7,677
Change in fair value	3,297
Reclassification of earnout liability upon Triggering Events	0
Ending balance	$ 10,974	$ 0

Fair Value - Fair Value Measure

Fair Value - Fair Value Measurement Valuation (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)$ / shares	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)$ / shares	Sep. 30, 2020USD ($)	Sep. 29, 2021$ / shares	Jul. 30, 2021USD ($)$ / shares	Dec. 31, 2020USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities	$ 34,294		$ 34,294			$ 22,000	$ 0
Change in fair value of derivative warrant liabilities	12,261	$ 0	12,261	$ 0
Private Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities	7,700		7,700
Change in fair value of derivative warrant liabilities	$ (3,300)		$ (3,300)
Stock price (USD per share)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities, measurement input | $ / shares	13.59		13.59			10.99
Stock price (USD per share) | Earnout Liabilities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Earnout liabilities, measurement input | $ / shares	13.59		13.59		13.59	10.99
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities, measurement input	0.0094		0.0094			0.0069
Risk-free interest rate | Earnout Liabilities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Earnout liabilities, measurement input	0.0129		0.0129		0.0129	0.0100
Expected term (in years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities, term	4 years 9 months 18 days		4 years 9 months 18 days			5 years
Expected term (in years) | Earnout Liabilities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Earnout liabilities, earnout period	6 years 9 months 18 days		6 years 9 months 18 days		6 years 9 months 18 days	7 years
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities, measurement input	0.3650		0.3650			0.3150
Expected volatility | Earnout Liabilities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Earnout liabilities, measurement input	0.5650		0.5650		0.5650	0.5720
Dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative warrant liabilities, measurement input	0		0			0
Dividend yield | Earnout Liabilities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Earnout liabilities, measurement input	0		0		0	0

Fair Value - Additional Informa

Fair Value - Additional Information (Details) $ / shares in Units, $ in Thousands	Oct. 06, 2021shares	Sep. 29, 2021USD ($)$ / sharesshares	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2020USD ($)	Jul. 30, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)
Class of Stock [Line Items]
Earnout liabilities			$ 266,390		$ 266,390		$ 228,100	$ 0
Change in fair value, loss on earnout liabilities			71,318	$ 0	71,318	$ 0
Derivative warrant liabilities			34,294		34,294		$ 22,000	$ 0
Change in fair value of derivative warrant liabilities			(12,261)	$ 0	(12,261)	$ 0
Private Warrants
Class of Stock [Line Items]
Derivative warrant liabilities			7,700		7,700
Change in fair value of derivative warrant liabilities			$ 3,300		$ 3,300
Earnout Liabilities | Expected term (in years)
Class of Stock [Line Items]
Earnout liabilities, earnout period		6 years 9 months 18 days	6 years 9 months 18 days		6 years 9 months 18 days		7 years
Earnout Liabilities | Dividend yield
Class of Stock [Line Items]
Earnout liabilities, measurement input		0	0		0		0
Rover Earnout Shares
Class of Stock [Line Items]
Earnout liabilities			$ 266,400		$ 266,400
Earnout shares (in shares) | shares			19,734,000		19,734,000		19,734,183
Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout shares issued (in shares) | shares		1,969,302
Earnout liabilities		$ 33,000
Earnout shares (in shares) | shares			492,000		492,000		2,461,627
Subsequent Event | Rover Earnout Shares
Class of Stock [Line Items]
Earnout shares issued (in shares) | shares	17,540,964
Derivative Instrument, Period, One And Two | Rover Earnout Shares
Class of Stock [Line Items]
Earnout liabilities			$ 238,400		$ 238,400
Derivative Instrument, Period, One And Two | Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout liabilities		26,700
Derivative Instrument, Period, One | Rover Earnout Shares
Class of Stock [Line Items]
Earnout period, stock price trigger (in dollars per share) | $ / shares			$ 12		$ 12		$ 12
Earnout shares (in shares) | shares							8,770,748
Derivative Instrument, Period, One | Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout period, stock price trigger (in dollars per share) | $ / shares							$ 12
Earnout shares (in shares) | shares							984,651
Derivative Instrument, Period, Two | Rover Earnout Shares
Class of Stock [Line Items]
Earnout period, stock price trigger (in dollars per share) | $ / shares			$ 14		$ 14		$ 14
Earnout shares (in shares) | shares							8,770,748
Derivative Instrument, Period, Two | Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout period, stock price trigger (in dollars per share) | $ / shares							$ 14
Earnout shares (in shares) | shares							984,651
Derivative Instrument, Period, Three | Rover Earnout Shares
Class of Stock [Line Items]
Earnout liabilities			$ 28,000		$ 28,000
Earnout period, stock price trigger (in dollars per share) | $ / shares			$ 16		$ 16		$ 16
Earnout shares (in shares) | shares			2,192,687		2,192,687
Derivative Instrument, Period, Three | Sponsor Earnout Shares
Class of Stock [Line Items]
Earnout liabilities		$ 6,300
Earnout period, stock price trigger (in dollars per share) | $ / shares		$ 16
Earnout shares (in shares) | shares							492,325

Balance Sheet Components - Prop

Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 41,233		$ 41,233		$ 39,762	$ 42,336
Less: Accumulated depreciation and amortization		(19,281)		(19,281)		(14,839)	(11,345)
Total property and equipment, net		21,952		21,952		24,923	30,991
Depreciation and amortization				10,815	$ 15,099	18,713	13,596	$ 9,656
Internal-use software amortization	$ 2,600	1,700	$ 1,800	5,200	5,600	7,200	5,200	2,500
Depreciation And Amortization
Property, Plant and Equipment [Line Items]
Depreciation and amortization		1,000	$ 900	2,900	$ 2,700	3,700	600	$ 600
Computers
Property, Plant and Equipment [Line Items]
Total property and equipment		1,632		1,632		1,346	1,534
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment		3,857		3,857		3,906	3,913
Furniture and fixtures | Seattle and Spokane, Washington
Property, Plant and Equipment [Line Items]
Total property and equipment						2,700
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment		13,663		13,663		13,660	13,136
Leasehold improvements | Seattle and Spokane, Washington
Property, Plant and Equipment [Line Items]
Total property and equipment						12,100
Internal-use software
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 22,081		$ 22,081		$ 20,850	$ 23,753

Balance Sheet Components - Accr

Balance Sheet Components - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued merchant fees	$ 8	$ 172	$ 778
Income and other tax liabilities	1,012	185	711
Accrued legal expenses and open claims	1,017	382	656
Lease incentive, current	0	491	453
Coupon liabilities		226	352
Accrued interest	14	259	0
Accrued professional services	540	872	213
Series G preferred stock holdback liability		0	320
Other current liabilities		160	1,180
Other current liabilities	238	386
Accrued expenses and other current liabilities	$ 2,829	$ 2,747	$ 4,663

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Summary of Changes in Carrying Amounts of Goodwill (Details)	12 Months Ended
	Dec. 31, 2019USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Balance	$ 34,811,000
Measurement period adjustment – DogBuddy	(1,652,000)
Balance	$ 33,159,000

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment	$ 0	$ 0	$ 0	$ 0
Amortization of intangible assets	900,000	1,200,000	2,700,000	4,200,000	$ 5,200,000	$ 7,700,000	$ 6,600,000
Intangible asset impairment loss	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Book Value		$ 19,240	$ 19,240	$ 29,340
Accumulated Amortization		(13,980)	(11,273)	(16,189)
Net Book Value		5,260	7,967	13,151
Pet parent relationships
Finite-Lived Intangible Assets [Line Items]
Gross Book Value		16,290	16,290	16,290
Accumulated Amortization		(11,181)	(9,117)	(6,364)
Net Book Value		$ 5,109	7,173	9,926
Remaining amortization period	4 years 3 months 18 days	4 years 2 months 12 days
Technologies
Finite-Lived Intangible Assets [Line Items]
Gross Book Value				10,100
Accumulated Amortization				(8,525)
Net Book Value				1,575
Pet service provider relationships
Finite-Lived Intangible Assets [Line Items]
Gross Book Value		$ 2,000	2,000	2,000
Accumulated Amortization		(1,944)	(1,444)	(778)
Net Book Value		$ 56	556	1,222
Remaining amortization period	9 months 18 days	1 month 6 days
Tradenames
Finite-Lived Intangible Assets [Line Items]
Gross Book Value		$ 950	950	950
Accumulated Amortization		(855)	(712)	(522)
Net Book Value		$ 95	$ 238	$ 428
Remaining amortization period	1 year 3 months 18 days	6 months

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Future Amortization Expense (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
2021	$ 792	$ 3,499
2022	1,347	1,347
2023	814	814
2024	814	814
2025	814	814
Thereafter	679	679
Net Book Value	$ 5,260	$ 7,967	$ 13,151

Debt (Details)

Debt (Details) - USD ($)	Jul. 30, 2021	Apr. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities				$ 0	$ 64,282,000	$ 64,563,000	$ 0	$ 0
Loan received from Small Business Administration's Paycheck Protection Program		$ 8,100,000
Repayments of lines of credit				38,124,000	$ 26,439,000	26,439,000	$ 0	$ 0
Repayments of small business administration's paycheck protection program	$ 8,100,000
Final termination payment	900,000
Accelerated unamortized debt issuance costs	400,000
Debt outstanding				$ 0		$ 38,124,000
Line of Credit | Variable Rate Revolving Line Of Credit
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities			$ 11,400,000
Line of Credit | Variable Rate Growth Capital Advance Components
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities			15,000,000
Line of Credit | Subordinated Credit Facility
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities			$ 30,000,000
Repayments of lines of credit	$ 30,000,000

Debt - Revolving Line of Credit

Debt - Revolving Line of Credit (Details) - USD ($)	1 Months Ended		9 Months Ended		12 Months Ended
	Aug. 31, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities			$ 0	$ 64,282,000	$ 64,563,000	$ 0	$ 0
Repayments of lines of credit			$ 38,124,000	$ 26,439,000	$ 26,439,000	$ 0	$ 0
Line of Credit | Variable Rate Revolving Line Of Credit
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities		$ 11,400,000
Revolving Credit Facility | Line of Credit | Variable Rate Revolving Line Of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 15,000,000
Interest rate	4.50%
Interest rate at period end			4.50%		4.50%
Interest rate, if certain milestones are achieved	4.00%
Unused credit facility fee	0.30%
Proceeds from borrowing on credit facilities					$ 11,400,000
Repayments of lines of credit					11,400,000
Revolving Credit Facility | Line of Credit | Variable Rate Revolving Line Of Credit | Prime Rate
Debt Instrument [Line Items]
Basis spread	0.50%
Letter of Credit | Line of Credit | Variable Rate Revolving Line Of Credit
Debt Instrument [Line Items]
Letter of credit			$ 3,500,000		$ 3,500,000

Debt - Growth Capital Advance (

Debt - Growth Capital Advance (Details)	9 Months Ended		12 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Aug. 31, 2020USD ($)tranche
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities	$ 0	$ 64,282,000	$ 64,563,000	$ 0	$ 0
Repayments of lines of credit	38,124,000	$ 26,439,000	26,439,000	$ 0	$ 0
Debt outstanding	0		38,124,000
Line of Credit | Growth Capital Advance Line Of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Number of tranches | tranche						3
Maximum borrowing capacity, under each tranche						$ 5,000,000
Maximum borrowing capacity						$ 15,000,000
Proceeds from borrowing on credit facilities			15,000,000
Repayments of lines of credit			$ 15,000,000
Debt outstanding	$ 0

Debt - Subordinated Credit Faci

Debt - Subordinated Credit Facility (Details) - USD ($)	Jul. 30, 2021	Mar. 31, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2021
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities				$ 0	$ 64,282,000	$ 64,563,000	$ 0	$ 0
Repayments of lines of credit				$ 38,124,000	26,439,000	26,439,000	$ 0	$ 0
Line of Credit
Debt Instrument [Line Items]
Covenant compliance, overall liquidity threshold						$ 75,000,000			$ 65,000,000
Line of Credit | Subordinated Credit Facility
Debt Instrument [Line Items]
Proceeds from borrowing on credit facilities		$ 30,000,000
Repayments of lines of credit	$ 30,000,000
Line of Credit | Subordinated Credit Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		30,000,000	$ 30,000,000
Interest rate at period end				7.50%		7.50%
Debt issuance costs			$ 269,000		$ 269,000
Proceeds from borrowing on credit facilities		$ 30,000,000
Repayments of lines of credit	30,000,000
Repayments of accrued interest	$ 200,000
Line of Credit | Subordinated Credit Facility | Revolving Credit Facility | Prime Rate
Debt Instrument [Line Items]
Basis spread			4.25%		4.25%

Debt - Small Business Administr

Debt - Small Business Administration's Paycheck Protection Program (Details) - USD ($) $ in Millions	Jul. 30, 2021	Apr. 30, 2020
Debt Instrument [Line Items]
Loan received from Small Business Administration's Paycheck Protection Program		$ 8.1
Repayments of small business administration's paycheck protection program	$ 8.1
PPP Loan
Debt Instrument [Line Items]
Loan received from Small Business Administration's Paycheck Protection Program		$ 8.1
Repayments of small business administration's paycheck protection program	8.1
Repayments of accrued interest	$ 0.1

Debt - Additional Information (

Debt - Additional Information (Details) - USD ($)	Apr. 01, 2020	Sep. 30, 2021	Dec. 31, 2020	May 31, 2018
Debt Instrument [Line Items]
Debt maturity date			Apr. 30, 2022
Debt outstanding		$ 0	$ 38,124,000
Line of credit facility, Interest rate accrued	1.00%
Small Business Administration’s Paycheck Protection Program
Debt Instrument [Line Items]
Debt maturity date			Apr. 30, 2022
Loan
Debt Instrument [Line Items]
Debt outstanding			$ 8,100,000
Credit Facility Agreement
Debt Instrument [Line Items]
Debt instrument, principal				$ 30,000,000
Long-term line of credit				15,000,000
Growth capital advance				$ 15,000,000
Debt maturity date			May 31, 2020
Credit Facility Agreement
Debt Instrument [Line Items]
Debt maturity date			May 31, 2022
Subordinated Credit Facility Agreement
Debt Instrument [Line Items]
Debt maturity date			Aug. 31, 2022
Revolving Credit Facility
Debt Instrument [Line Items]
Debt maturity date			May 31, 2022
Amount available to borrow under revolving line of credit			$ 11,400,000
Line of credit facility, description		Interest accrues at the greater of (1) 4.50% and (2) the Prime Rate plus a margin of 0.50% per year (4.50% at December 31, 2020), unless certain milestones are achieved then interest accrues at the greater of (1) 4.00% and (2) the Prime Rate. Interest is payable monthly.
Line of credit facility, debt issuance costs			$ 22,500
Line of credit facility, expiration date			May 31, 2022
Growth Capital Advance Component
Debt Instrument [Line Items]
Debt instrument, principal			$ 1,000,000
Debt maturity date			Jun. 30, 2024
Line of credit facility, Interest rate accrued		5.00%
Percentage of pay unused credit facility fee to lender		0.50%
Amount available to borrow under revolving line of credit			$ 15,000,000
Line of credit facility, description		the lender agreed to make advances to the Company in three tranches not to exceed $5.0 million under each tranche, up to the total amount of $15.0 million during the draw period, which was available until June 30, 2021.
Line of credit facility, debt issuance costs		$ 25,000
Loss recognized from early prepayment			$ 353,000
Growth Capital Advance Component | Debt Instrument Milestone Achieved
Debt Instrument [Line Items]
Line of credit facility, Interest rate accrued		4.50%
Growth Capital Advance Component | Prime Rate
Debt Instrument [Line Items]
Interest rate at period end		1.00%
Line of credit facility, Interest rate			5.00%
Subordinate Credit Facility
Debt Instrument [Line Items]
Borrowed and repaid amount		$ 5,000,000
Amount available to borrow under revolving line of credit			$ 30,000,000
Subordinated Debt
Debt Instrument [Line Items]
Line of credit facility, expiration date			Aug. 31, 2022
Growth Capital Advance
Debt Instrument [Line Items]
Line of credit facility, expiration date			Jun. 30, 2024

Debt - Schedule of Future Minim

Debt - Schedule of Future Minimum Payments of Outstanding Debt Borrowings (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
2021		$ 4,505,000
2022		33,619,000
2023		0
2024		0
2025		0
Total principal amount	$ 0	38,124,000
Unamortized discount		(598,000)
Carrying value of debt		$ 37,526,000

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details)	1 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2021USD ($)facility	Feb. 29, 2020USD ($)	Sep. 30, 2018facility	Sep. 30, 2020USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2021USD ($)
Lessee, Lease, Description [Line Items]
Number of leased facilities | facility	1		1
Sublease, option to extend period	1 year	2 years
Sublease income, additional base lease payments	$ 1,700,000	$ 1,400,000
Rent expense				$ 1,000,000	$ 2,800,000	$ 3,600,000	$ 4,000,000	$ 2,100,000
Sublease income				$ 200,000	$ 600,000	700,000	700,000	$ 100,000
Cease use liability							361,000
Remained cease use liability							$ 297,000
Indemnification Agreement
Lessee, Lease, Description [Line Items]
Loss contingency accrual						$ 0			$ 0
Office space | Minimum
Lessee, Lease, Description [Line Items]
Lease term									21 months
Renewal term									1 year
Office space | Maximum
Lessee, Lease, Description [Line Items]
Lease term									137 months
Renewal term									7 years

Commitments and Contingencies_2

Commitments and Contingencies - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 1,046	$ 3,011
Short-term lease cost	19	138
Sublease income	(304)	(649)
Total lease cost	$ 761	$ 2,500

Commitments and Contingencies_3

Commitments and Contingencies - Other Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Cash paid for operating lease liabilities	$ 3,159
Weighted-average discount rate	7.12%
Weighted-average remaining lease term (years)	7 years 10 months 17 days

Commitments and Contingencies_4

Commitments and Contingencies - Lease Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 01, 2021	Dec. 31, 2020	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2021				$ 1,156
2022				4,669
2023				4,700
2024				4,563
2025				4,693
Thereafter				18,209
Total lease payments				37,990
Less: imputed interest				(9,331)
Present value of lease liabilities		$ 29,600		28,659
Less: current portion of lease liabilities	$ (2,726)		$ 0	(2,726)
Total lease liabilities, noncurrent	$ 25,933		$ 0	$ 25,933

Commitments and Contingencies_5

Commitments and Contingencies - Lease Maturity Under ASC 840 (Details) $ in Thousands	Dec. 31, 2020USD ($)
Commitments and Contingencies Disclosure [Abstract]
2021	$ 4,356
2022	4,303
2023	4,433
2024	4,563
2025	4,693
Thereafter	18,209
Total	$ 40,557

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020USD ($)
Retirement Benefits [Abstract]
Employer discretionary contribution amount	$ 0

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Outstanding Redeemable Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2021	[1]	Jul. 30, 2021	Jul. 29, 2021	Jun. 30, 2021	[1]	Mar. 31, 2021	[1]	Dec. 31, 2020		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Dec. 31, 2018	[2]	Dec. 31, 2017	[2]
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)			87,611,000						87,611,000					87,611,000
Redeemable convertible preferred stock, issued									90,814,000					90,805,000
Redeemable convertible preferred stock, outstanding	0			87,496,938	90,814,000		90,814,000		90,814,000	[1]	90,814,000	90,814,000	90,814,000	90,805,000	[2]	90,305,000		71,692,000
Redeemable convertible preferred stock, net carrying value									$ 290,427					$ 290,365
Redeemable convertible preferred stock, aggregate liquidation preference									$ 294,802					$ 294,740
Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									8,710,000					8,710,000
Redeemable convertible preferred stock, issued									9,040,000					9,040,000
Redeemable convertible preferred stock, outstanding									9,040,000					9,040,000
Convertible preferred stock, par value (in dollars per share)									$ 0.4478					$ 0.4478
Redeemable convertible preferred stock, net carrying value									$ 3,325					$ 3,325
Redeemable convertible preferred stock, aggregate liquidation preference									$ 4,048					$ 4,048
Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									14,104,000					14,104,000
Redeemable convertible preferred stock, issued									14,639,000					14,639,000
Redeemable convertible preferred stock, outstanding									14,639,000					14,639,000
Convertible preferred stock, par value (in dollars per share)									$ 0.6528					$ 0.6528
Redeemable convertible preferred stock, net carrying value									$ 9,397					$ 9,397
Redeemable convertible preferred stock, aggregate liquidation preference									$ 9,556					$ 9,556
Series C Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									12,431,000					12,431,000
Redeemable convertible preferred stock, issued									12,903,000					12,903,000
Redeemable convertible preferred stock, outstanding									12,903,000					12,903,000
Convertible preferred stock, par value (in dollars per share)									$ 1.1238					$ 1.1238
Redeemable convertible preferred stock, net carrying value									$ 14,596					$ 14,596
Redeemable convertible preferred stock, aggregate liquidation preference									$ 14,500					$ 14,500
Series D Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									7,677,000					7,677,000
Redeemable convertible preferred stock, issued									7,968,000					7,968,000
Redeemable convertible preferred stock, outstanding									7,968,000					7,968,000
Convertible preferred stock, par value (in dollars per share)									$ 2.0080					$ 2.0080
Redeemable convertible preferred stock, net carrying value									$ 14,036					$ 14,036
Redeemable convertible preferred stock, aggregate liquidation preference									$ 16,000					$ 16,000
Series D One Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									3,359,000					3,359,000
Redeemable convertible preferred stock, issued									3,486,000					3,486,000
Redeemable convertible preferred stock, outstanding									3,486,000					3,486,000
Convertible preferred stock, par value (in dollars per share)									$ 2.0078					$ 2.0080
Redeemable convertible preferred stock, net carrying value									$ 6,981					$ 6,981
Redeemable convertible preferred stock, aggregate liquidation preference									$ 7,000					$ 7,000
Series E Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									11,021,000					11,021,000
Redeemable convertible preferred stock, issued									11,439,000					11,439,000
Redeemable convertible preferred stock, outstanding									11,439,000					11,439,000
Convertible preferred stock, par value (in dollars per share)									$ 3.4969					$ 3.4968
Redeemable convertible preferred stock, net carrying value									$ 39,906					$ 39,906
Redeemable convertible preferred stock, aggregate liquidation preference									$ 40,000					$ 40,000
Series F Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									11,772,000					11,772,000
Redeemable convertible preferred stock, issued									12,218,000					12,218,000
Redeemable convertible preferred stock, outstanding									12,218,000					12,218,000
Convertible preferred stock, par value (in dollars per share)									$ 5.3199					$ 5.3200
Redeemable convertible preferred stock, net carrying value									$ 64,833					$ 64,833
Redeemable convertible preferred stock, aggregate liquidation preference									$ 65,000					$ 65,000
Series G Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									18,537,000					18,537,000
Redeemable convertible preferred stock, issued									19,121,000					19,112,000
Redeemable convertible preferred stock, outstanding									19,121,000					19,112,000
Convertible preferred stock, par value (in dollars per share)									$ 7.2536					$ 7.2539
Redeemable convertible preferred stock, net carrying value									$ 137,353					$ 137,291
Redeemable convertible preferred stock, aggregate liquidation preference									$ 138,698					$ 138,636
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) - $ / shares	Sep. 30, 2021	Jul. 30, 2021	Jul. 29, 2021	Dec. 31, 2020	Dec. 31, 2019
Equity [Abstract]
Common stock, shares authorized (in shares)	990,000,000			144,250,000	144,250,000
Common stock, par value (in dollars per share)	$ 0.0001			$ 0.0001	$ 0.0001
Common stock, shares issued (in shares)	157,593,000			30,398,000	29,614,000
Common stock, shares outstanding (in shares)	157,593,000	157,199,138	32,434,987	30,398,000	29,614,000
Number of common shares issued for each share of preferred stock (in shares)		1
Preferred stock, shares authorized (in shares)	10,000,000			0
Preferred stock, par value (in dollars per share)	$ 0.0001			$ 0.0001
Preferred stock, shares issued (in shares)	0			0
Preferred stock, shares outstanding (in shares)	0			0

Stockholders' Equity - Schedu_2

Stockholders' Equity - Schedule of reserved shares of common stock for issuance, on an as-converted basis (Details) - shares	Sep. 30, 2021		Jul. 30, 2021	Jul. 29, 2021	Jun. 30, 2021	[1]	Mar. 31, 2021	[1]	Dec. 31, 2020		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017	[2]
Capital Unit [Line Items]
Conversion of redeemable convertible preferred stock (in shares)	0	[1]		87,496,938	90,814,000		90,814,000		90,814,000	[1]	90,814,000	90,814,000	90,814,000	90,805,000	[2]	90,305,000	[2]	71,692,000
Warrants outstanding (in shares)	8,074,164								1,118,000					790,000
Stock options issued and outstanding (in shares)	19,955,000								24,700,000					24,911,000		20,578,000
Shares available for future option grants (in shares)	17,258,000								5,199,000					4,094,000
Total (in shares)	65,513,000								121,831,000					120,600,000
Rover Earnout Shares
Capital Unit [Line Items]
Earnout shares (in shares)	19,734,000		19,734,183
Sponsor Earnout Shares
Capital Unit [Line Items]
Earnout shares (in shares)	492,000		2,461,627
Private Warrants
Capital Unit [Line Items]
Warrants outstanding (in shares)	2,574,000		2,574,164	5,166,667
Public Warrants
Capital Unit [Line Items]
Warrants outstanding (in shares)	5,500,000		5,500,000
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Common Stock - Additional Infor

Common Stock - Additional Information (Details) - USD ($)	Aug. 05, 2019	Aug. 09, 2018	May 23, 2018	Mar. 29, 2017	Mar. 20, 2020	Aug. 05, 2019	Sep. 30, 2021	Jul. 30, 2021	Jul. 29, 2021	Dec. 31, 2020	Dec. 31, 2019
Stockholders Equity [Line Items]
Common stock, shares authorized (in shares)							990,000,000			144,250,000	144,250,000
Common stock, par value (in dollars per share)							$ 0.0001			$ 0.0001	$ 0.0001
Common stock, shares outstanding (in shares)							157,593,000	157,199,138	32,434,987	30,398,000	29,614,000
Issuance of warrant to purchase shares		487,816	26,940
Warrant to purchase shares at exercise price		$ 3.11	$ 3.11
Credit Facility
Stockholders Equity [Line Items]
Issuance of warrant to purchase shares					139,192	13,470
Warrant to purchase shares at exercise price					$ 3.11	$ 3.11
Long-term line of credit					$ 15,000,000
Subordinate Credit Facility
Stockholders Equity [Line Items]
Issuance of warrant to purchase shares	50,984				94,686
Warrant to purchase shares at exercise price	$ 3.52				$ 3.52
Subordinated Debt					$ 30,000,000
Black Scholes Option Pricing Model
Stockholders Equity [Line Items]
Warrant valuation		$ 642,000	$ 50,000
Fair value assumptions price per share		$ 3.11	$ 3.11
Percentage of risk free interest rate		2.78%	2.99%
Contractual term		4 years 10 months 17 days	10 years
Expected dividend rate		0.00%	0.00%
Expected volatility rate		45.00%	45.00%
Black Scholes Option Pricing Model | Credit Facility
Stockholders Equity [Line Items]
Warrant valuation					$ 276,000	$ 27,000
Fair value assumptions price per share	$ 3.52					$ 3.52
Percentage of risk free interest rate					0.86%	1.74%
Contractual term					8 years 2 months 12 days	8 years 9 months
Expected dividend rate					0.00%	0.00%
Expected volatility rate					49.00%	46.30%
Black Scholes Option Pricing Model | Subordinate Credit Facility
Stockholders Equity [Line Items]
Warrant valuation	$ 207,000				$ 189,000
Fair value assumptions price per share	$ 3.52				$ 3.53	$ 3.52
Percentage of risk free interest rate	1.74%				0.90%
Contractual term	10 years				9 years 4 months 24 days
Expected dividend rate	0.00%				0.00%
Expected volatility rate	46.30%				49.00%
DogVacay, Inc
Stockholders Equity [Line Items]
Issuance of warrant to purchase shares				26,000
DogVacay, Inc | Black Scholes Option Pricing Model
Stockholders Equity [Line Items]
Warrant valuation				$ 20,000
Fair value assumptions price per share				$ 1.52
Percentage of risk free interest rate				2.38%
Contractual term				10 years
Expected dividend rate				0.00%
Expected volatility rate				54.90%
DogVacay, Inc | Minimum
Stockholders Equity [Line Items]
Warrant to purchase shares at exercise price				$ 3.23
DogVacay, Inc | Maximum
Stockholders Equity [Line Items]
Warrant to purchase shares at exercise price				$ 3.41

Common Stock - Summary of Commo

Common Stock - Summary of Common Stock Shares Reserved for Future Issuance (Details) - shares	Sep. 30, 2021		Jul. 29, 2021	Jun. 30, 2021	[1]	Mar. 31, 2021	[1]	Dec. 31, 2020		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017	[2]
Equity [Abstract]
Redeemable convertible preferred stock, outstanding	0	[1]	87,496,938	90,814,000		90,814,000		90,814,000	[1]	90,814,000	90,814,000	90,814,000	90,805,000	[2]	90,305,000	[2]	71,692,000
Warrants outstanding (in shares)	8,074,164							1,118,000					790,000
Options outstanding under the 2011 Plan (in shares)	19,955,000							24,700,000					24,911,000		20,578,000
Shares available for future option grants (in shares)	17,258,000							5,199,000					4,094,000
Total (in shares)	65,513,000							121,831,000					120,600,000
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Redeemable Convertible Prefer_3

Redeemable Convertible Preferred Stock - Schedule of Outstanding Redeemable Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2021	[1]	Jul. 30, 2021	Jul. 29, 2021	Jun. 30, 2021	[1]	Mar. 31, 2021	[1]	Dec. 31, 2020		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Dec. 31, 2018	[2]	Dec. 31, 2017	[2]
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)			87,611,000						87,611,000					87,611,000
Redeemable convertible preferred stock, issued									90,814,000					90,805,000
Redeemable convertible preferred stock, outstanding	0			87,496,938	90,814,000		90,814,000		90,814,000	[1]	90,814,000	90,814,000	90,814,000	90,805,000	[2]	90,305,000		71,692,000
Redeemable convertible preferred stock, net carrying value									$ 290,427					$ 290,365
Redeemable convertible preferred stock, aggregate liquidation preference									$ 294,802					$ 294,740
Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									8,710,000					8,710,000
Redeemable convertible preferred stock, issued									9,040,000					9,040,000
Redeemable convertible preferred stock, outstanding									9,040,000					9,040,000
Convertible preferred stock, par value (in dollars per share)									$ 0.4478					$ 0.4478
Redeemable convertible preferred stock, net carrying value									$ 3,325					$ 3,325
Redeemable convertible preferred stock, aggregate liquidation preference									$ 4,048					$ 4,048
Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									14,104,000					14,104,000
Redeemable convertible preferred stock, issued									14,639,000					14,639,000
Redeemable convertible preferred stock, outstanding									14,639,000					14,639,000
Convertible preferred stock, par value (in dollars per share)									$ 0.6528					$ 0.6528
Redeemable convertible preferred stock, net carrying value									$ 9,397					$ 9,397
Redeemable convertible preferred stock, aggregate liquidation preference									$ 9,556					$ 9,556
Series C Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									12,431,000					12,431,000
Redeemable convertible preferred stock, issued									12,903,000					12,903,000
Redeemable convertible preferred stock, outstanding									12,903,000					12,903,000
Convertible preferred stock, par value (in dollars per share)									$ 1.1238					$ 1.1238
Redeemable convertible preferred stock, net carrying value									$ 14,596					$ 14,596
Redeemable convertible preferred stock, aggregate liquidation preference									$ 14,500					$ 14,500
Series D Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									7,677,000					7,677,000
Redeemable convertible preferred stock, issued									7,968,000					7,968,000
Redeemable convertible preferred stock, outstanding									7,968,000					7,968,000
Convertible preferred stock, par value (in dollars per share)									$ 2.0080					$ 2.0080
Redeemable convertible preferred stock, net carrying value									$ 14,036					$ 14,036
Redeemable convertible preferred stock, aggregate liquidation preference									$ 16,000					$ 16,000
Series D One Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									3,359,000					3,359,000
Redeemable convertible preferred stock, issued									3,486,000					3,486,000
Redeemable convertible preferred stock, outstanding									3,486,000					3,486,000
Convertible preferred stock, par value (in dollars per share)									$ 2.0078					$ 2.0080
Redeemable convertible preferred stock, net carrying value									$ 6,981					$ 6,981
Redeemable convertible preferred stock, aggregate liquidation preference									$ 7,000					$ 7,000
Series E Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									11,021,000					11,021,000
Redeemable convertible preferred stock, issued									11,439,000					11,439,000
Redeemable convertible preferred stock, outstanding									11,439,000					11,439,000
Convertible preferred stock, par value (in dollars per share)									$ 3.4969					$ 3.4968
Redeemable convertible preferred stock, net carrying value									$ 39,906					$ 39,906
Redeemable convertible preferred stock, aggregate liquidation preference									$ 40,000					$ 40,000
Series F Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									11,772,000					11,772,000
Redeemable convertible preferred stock, issued									12,218,000					12,218,000
Redeemable convertible preferred stock, outstanding									12,218,000					12,218,000
Convertible preferred stock, par value (in dollars per share)									$ 5.3199					$ 5.3200
Redeemable convertible preferred stock, net carrying value									$ 64,833					$ 64,833
Redeemable convertible preferred stock, aggregate liquidation preference									$ 65,000					$ 65,000
Series G Convertible Preferred Stock
Temporary Equity [Line Items]
Redeemable convertible preferred stock, authorized (in shares)									18,537,000					18,537,000
Redeemable convertible preferred stock, issued									19,121,000					19,112,000
Redeemable convertible preferred stock, outstanding									19,121,000					19,112,000
Convertible preferred stock, par value (in dollars per share)									$ 7.2536					$ 7.2539
Redeemable convertible preferred stock, net carrying value									$ 137,353					$ 137,291
Redeemable convertible preferred stock, aggregate liquidation preference									$ 138,698					$ 138,636
[1]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.
[2]	The shares of the Company's common and redeemable convertible preferred stock, prior to the Merger, have been retroactively restated as shares reflecting the exchange ratio of approximately 1.0379 established in the Merger described in Note 1.

Redeemable Convertible Prefer_4

Redeemable Convertible Preferred Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 31, 2018	Feb. 29, 2020	Nov. 30, 2019	Dec. 31, 2020
Temporary Equity [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)		9,000
DogBuddy
Temporary Equity [Line Items]
Number of shares, acquired		100,000
Series G Preferred Stock
Temporary Equity [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)			500,000
Series G Preferred Stock | DogBuddy
Temporary Equity [Line Items]
Change in value of Class A common stock subject to possible redemption (in Shares)	539,000		500,000
Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				$ 0.4478
Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				0.6528
Series C Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				1.1238
Series D Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				2.0080
Series D One Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				2.0078
Series E Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				3.4969
Series F Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				$ 5.3199
Line of credit facility, Interest rate				56.00%
Series G Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock liquidation preference, per share				$ 7.2536
Common Stock
Temporary Equity [Line Items]
Gross proceeds				$ 50
Line of credit facility, Interest rate				70.00%
Common Stock | DogBuddy
Temporary Equity [Line Items]
Number of shares, acquired	1,400,000		3,600,000

Stock Warrants - Narrative (Det

Stock Warrants - Narrative (Details) - $ / shares	Jul. 30, 2021	Sep. 30, 2021	Sep. 14, 2021	Jul. 29, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)		8,074,164			1,118,000	790,000
Number of shares called by each warrant (in shares)	1	1
Exercise price of warrant (in dollars per share)	$ 11.50	$ 11.50
Period which warrants or rights are exercisable	5 years
Number of shares of common stock called by warrants (in shares)			8,074,164
Number of warrants exercised (in shares)	631,000	0
Issuance of common stock from net exercises of warrants (in shares)	448,000
Private Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	2,574,164	2,574,000		5,166,667
Warrants, forfeited (in shares)	2,592,503
Period where warrants are not transferable, assignable or salable, after merger completion		30 days
Public Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	5,500,000	5,500,000
Exercise price of warrant (in dollars per share)		$ 11.50
Warrants, minimum number of days for written notice of redemption		30 days
Redemption price per warrant (in dollars per share)		$ 0.01
Reference value of common stock for warrants to be redeemed (in dollars per share)		$ 18
Warrant, number of trading days of sale price of common stock for redemption		20 days
Warrant, number of consecutive trading days		30 days
Common Stock Warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)		0

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details)	Aug. 23, 2011shares	Jul. 31, 2020USD ($)$ / sharesshares	Apr. 30, 2020USD ($)shares	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2021USD ($)$ / sharesshares	Mar. 31, 2021USD ($)	Sep. 30, 2020USD ($)$ / shares	Mar. 31, 2020USD ($)	Mar. 31, 2019USD ($)	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2020USD ($)$ / shares	Dec. 31, 2020USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares	Jul. 30, 2021shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)				65,513,000	65,513,000					65,513,000		121,831,000	120,600,000
Weighted-average grant-date fair value of options granted (in dollars per share) | $ / shares							$ 0.21				$ 0.49	$ 0.59	$ 1.51	$ 1.29
Aggregate intrinsic value of stock options exercised | $					$ 14,500,000		$ 200,000			$ 19,900,000	$ 700,000	$ 2,400,000	$ 2,100,000	$ 3,400,000
Fair value of options vested | $					900,000		1,200,000			2,900,000	4,000,000	5,000,000	4,100,000	2,200,000
Stock-based compensation expense | $					994,000		1,789,000			3,142,000	4,268,000	5,541,000	$ 4,067,000	$ 6,682,000
Common stock investors acquired														1,300,000
Common stock premium per share (in usd per share) | $ / shares														$ 3.42
Number of shares offered														1,300,000
Shares purchased from employee														1,200,000
Shares purchased from non employee														144,000
Deemed dividend amount | $														$ 491,000
Income tax benefit related to stock-based compensation | $					0	$ 0	0	$ 0	$ 0	0	0
Unrecognized compensation cost related to unvested stock options | $				$ 5,300,000	$ 5,300,000					$ 5,300,000		$ 8,700,000
Percent of positions eliminated (in percentage)			50.00%
Weighted-average remaining contractual term of vested stock options (days)			3 years					90 days
Options outstanding under the 2011 Plan (in shares)				19,955,000	19,955,000					19,955,000		24,700,000	24,911,000	20,578,000
Weighted-average exercise price of outstanding options held by current employees (in dollars per share) | $ / shares				$ 1.53	$ 1.53					$ 1.53		$ 1.45	$ 1.65	$ 1.27
Weighted average remaining contractual term of options outstanding										6 years 1 month 6 days		6 years 4 months 24 days	7 years 1 month 6 days	7 years 4 months 24 days
Incremental intrinsic value of vested options held by current employees | $		$ 400,000
Shares per option (in shares)				1.2006
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense | $					$ 593,000		1,056,000			$ 1,779,000	2,200,000	$ 2,972,000	$ 2,003,000	$ 3,904,000
General and administrative | Secondary Market Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense | $														2,700,000
Product Development | Secondary Market Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense | $														$ 1,500,000
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual term for unvested stock options										1 year 10 months 24 days		2 years 6 months
Number of shares available for grant				17,258,000	17,258,000					17,258,000		5,199,000	4,094,000	2,190,000
Modified options | Terminated Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense | $			$ 300,000
Options outstanding under the 2011 Plan (in shares)			3,102,000
Modified options | Current Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense | $					$ 100,000		$ 500,000			$ 300,000	$ 500,000	$ 600,000
Unrecognized compensation cost related to unvested stock options | $				$ 400,000	$ 400,000					$ 400,000		$ 600,000
Options outstanding under the 2011 Plan (in shares)		6,800,000
Exercise price threshold (in dollars per share) | $ / shares		$ 1.99
Weighted-average exercise price of outstanding options held by current employees (in dollars per share) | $ / shares		$ 1.99
Weighted average remaining contractual term of options outstanding		10 years
Dog Vacay Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)												553,000
Dog Buddy Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)												65,000
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)	29,000,000
Award vesting period	4 years
Expiration period	10 years
Options outstanding under the 2011 Plan (in shares)															20,400,000
2021 Plan | Share-based Payment Arrangement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)				17,300,000	17,300,000					17,300,000					17,200,000

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Options Available for Grant
Grants in period (in shares)	0	(11,258,000)	(6,897,000)
Number of options cancelled and forfeited (in shares)	(1,864,000)	(10,562,000)	(1,598,000)
Number of Options Outstanding
Number of options outstanding at period start (in shares)	24,700,000	24,911,000	20,578,000
Grants in period (in shares)	0	11,258,000	6,897,000
Number of options exercised (in shares)	(2,881,000)	(907,000)	(966,000)
Number of options cancelled and forfeited (in shares)	(1,864,000)	(10,562,000)	(1,598,000)
Number of options outstanding at period end (in shares)	19,955,000	24,700,000	24,911,000	20,578,000
Number of options vested and exercisable (in shares)	15,369,000	17,262,000
Weighted- Average Exercise Price Per Share
Weighted average exercise price of outstanding options at period start (in usd per shares)	$ 1.45	$ 1.65	$ 1.27
Weighted average exercise price of options granted (in usd per shares)		2.08	2.77
Weighted average exercise price of options exercised (in usd per shares)	1.08	0.85	0.82
Weighted average exercise price of options cancelled and forfeited (in usd per shares)	2.68	2.67	2.09
Weighted average exercise price of outstanding options at period end (in usd per shares)	1.53	1.45	$ 1.65	$ 1.27
Weighted average exercise price of options vested and exercisable (in usd per shares)	$ 1.36	$ 1.20
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual term of options outstanding	6 years 1 month 6 days	6 years 4 months 24 days	7 years 1 month 6 days	7 years 4 months 24 days
Weighted average remaining contractual term of options vested and exercisable	5 years 6 months	5 years 6 months
Aggregate intrinsic value of options outstanding	$ 240,692	$ 83,570	$ 34,776
Aggregate intrinsic value of options vested and exercisable	$ 187,904	$ 62,719
Previously Reported
Number of Options Outstanding
Number of options outstanding at period start (in shares)	20,574,000
Number of options outstanding at period end (in shares)		20,574,000
Weighted- Average Exercise Price Per Share
Weighted average exercise price of outstanding options at period start (in usd per shares)	$ 1.74
Weighted average exercise price of outstanding options at period end (in usd per shares)		$ 1.74
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual term of options outstanding		6 years 4 months 24 days
Aggregate intrinsic value of options outstanding		$ 83,570
Retroactive application of reverse recapitalization
Number of Options Outstanding
Number of options outstanding at period start (in shares)	4,126,000
Number of options outstanding at period end (in shares)		4,126,000
Outstanding stock options
Options Available for Grant
Number of shares available for grant at period start (in shares)	5,199,000	4,094,000	2,190,000
Number of additional shares authorized (in shares)	17,200,000	1,801,000	7,203,000
Number of options cancelled and forfeited (in shares)	(1,864,000)
Number of options cancelled in connection with termination of 2011 Plan (in shares)	(7,005,000)
Number of shares available for grant at period end (in shares)	17,258,000	5,199,000	4,094,000	2,190,000
Number of Options Outstanding
Number of options cancelled and forfeited (in shares)	(1,864,000)
Outstanding stock options | Previously Reported
Options Available for Grant
Number of shares available for grant at period start (in shares)	4,330,000
Number of shares available for grant at period end (in shares)		4,330,000
Outstanding stock options | Retroactive application of reverse recapitalization
Options Available for Grant
Number of shares available for grant at period start (in shares)	869,000
Number of shares available for grant at period end (in shares)		869,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Range of Assumptions Used to Estimate Fair Value of Options Granted (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	0.24%	1.38%	2.34%
Risk-free interest rate, maximum	1.43%	2.60%	3.08%
Volatility, minimum	49.00%	44.50%	44.50%
Volatility, maximum	54.80%	46.30%	50.60%
Dividend yield	0.00%	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	3 years 11 months 26 days	4 years 6 months 3 days	3 years 1 month 2 days
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	6 years 9 months 18 days	6 years 9 months	6 years 11 months 19 days

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($)	3 Months Ended					9 Months Ended		12 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 994,000		$ 1,789,000			$ 3,142,000	$ 4,268,000	$ 5,541,000	$ 4,067,000	$ 6,682,000
Income tax benefit related to stock-based compensation	0	$ 0	0	$ 0	$ 0	0	0
Operations and support
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	43,000		100,000			144,000	261,000	299,000	277,000	206,000
Marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	71,000		123,000			238,000	348,000	397,000	301,000	181,000
Product development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	287,000		510,000			981,000	1,459,000	1,873,000	1,486,000	2,391,000
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 593,000		$ 1,056,000			$ 1,779,000	$ 2,200,000	$ 2,972,000	$ 2,003,000	$ 3,904,000

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Loss before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S.					$ (56,758)	$ (48,650)	$ (63,467)
Foreign					(821)	(3,532)	(1,479)
Loss before income taxes	$ (84,500)	$ (10,429)	$ (98,213)	$ (49,105)	$ (57,579)	$ (52,182)	$ (64,946)

Income Taxes - Schedule of Co_2

Income Taxes - Schedule of Components of Provision for Benefit from Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current tax expense:
U.S. Federal					$ 0	$ 0	$ 0
State					(5)	(29)	0
Foreign					(204)	(91)	(9)
Total current					(209)	(120)	(9)
Deferred tax expense:
U.S. Federal					0	0	0
State					0	0	0
Foreign					303	588	278
Total deferred tax benefit			$ 309	$ 314	303	588	278
Total income tax benefit	$ (36)	$ 70	$ 280	$ 122	$ 94	$ 468	$ 269

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Statutory Federal Rate to the Company's Effective Tax Rate (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal income taxes at statutory rate					21.00%	21.00%	21.00%
State taxes, net of federal benefit					1.60%	1.70%	1.80%
Tax credits					0.20%	1.60%	1.30%
Equity compensation					(0.90%)	(1.00%)	(1.10%)
Change in valuation allowance					(20.90%)	(20.60%)	(21.30%)
Other, net					(0.80%)	(1.80%)	(1.30%)
Effective tax rate	0.00%	0.70%	0.30%	0.20%	0.20%	0.90%	0.40%

Income Taxes - Significant Comp

Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss carryforward	$ 55,649	$ 46,810
Tax credit carryforward	2,298	2,199
Reserves and accruals	909	1,030
Stock based compensation	1,011	498
Property, plant and equipment	214	0
Other	898	21
Total deferred tax assets	60,979	50,558
Less: Deferred tax assets valuation allowance	(57,225)	(45,180)
Total deferred tax assets, net of valuation allowance	3,754	5,378
Deferred tax liabilities:
Capitalized internal-use software costs	(2,477)	(3,223)
Intangibles	(42)	(1,076)
Property, plant and equipment	0	(153)
Total deferred tax liabilities	(2,519)	(4,452)
Net deferred tax assets	$ 1,235	$ 926

Income Taxes - Summary of Rollf

Income Taxes - Summary of Rollforward of Valuation Allowance (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	$ 45,180,000	$ 34,435,000	$ 20,620,000
Increase in valuation allowance	12,045,000	10,745,000	13,815,000
Balance	$ 57,225,000	$ 45,180,000	$ 34,435,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Likelihood of deferred tax assets not realized					50.00%
Change in ownership interest of significant stockholders					50.00%
Effective tax rate	0.00%	0.70%	0.30%	0.20%	0.20%	0.90%	0.40%
Increase in unrecognized tax benefits	$ 5		$ 12
Federal
Income Taxes [Line Items]
Net operating loss carryforwards					$ 234,800
Operating loss carryforwards, not subject to limitation					134,200
State
Income Taxes [Line Items]
Net operating loss carryforwards					80,500
Foreign
Income Taxes [Line Items]
Net operating loss carryforwards					$ 6,400

Income Taxes - Schedule of Gros

Income Taxes - Schedule of Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance	$ 550	$ 383	$ 218
Current year tax position increases	24	167	165
Balance	$ 574	$ 550	$ 383

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net loss	$ (84,536)	$ (2,806)	$ (10,591)	$ (10,359)	$ (18,079)	$ (20,545)	$ (97,933)	$ (48,983)	$ (57,485)	$ (51,714)	$ (64,677)
Deemed dividend to preferred stockholders									0	0	(491)
Net loss attributable to common stockholders									$ (57,485)	$ (51,714)	$ (65,168)
Weighted-average shares used in computing net loss per share, basic (in shares)	116,597,000			30,008,000			59,825,000	29,834,000	29,896,000	29,138,000	27,150,000
Weighted-average shares used in computing net loss per share, diluted (in shares)	116,597,000			30,008,000			59,825,000	29,834,000	29,896,000	29,138,000	27,150,000
Net loss per common share - basic (in dollars per share)	$ (0.73)			$ (0.35)			$ (1.64)	$ (1.64)	$ (1.92)	$ (1.77)	$ (2.40)
Net loss per common share - diluted (in dollars per share)	$ (0.73)			$ (0.35)			$ (1.64)	$ (1.64)	$ (1.92)	$ (1.77)	$ (2.40)

Net Loss Per Share Attributab_4

Net Loss Per Share Attributable to Common Stockholders (Details) - shares	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	28,521,000	117,413,000	116,632,000	116,506,000	111,557,000
Redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)		90,814,000	90,814,000	90,805,000	90,305,000
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	19,955,000	25,481,000	24,700,000	24,911,000	20,578,000
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)		1,118,000	1,118,000	790,000	674,000
Private Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	2,574,000
Public Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	5,500,000
Sponsor Earnout Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	492,000	0
Rover Earnout Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	2,192,687

Restructuring (Details)

Restructuring (Details) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2020	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2020	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Percent of positions eliminated (in percentage)	50.00%
Incurred cost	$ 3,800,000
Liability for restructuring-related costs				$ 0	$ 0
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		$ 512,000	$ 3,751,000	3,763,000
Operations and support
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		174,000	795,000	796,000
Marketing
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		84,000	592,000	593,000
Product development
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		138,000	1,741,000	1,743,000
General and administrative
Restructuring Cost and Reserve [Line Items]
Total restructuring charges		$ 116,000	$ 623,000	$ 631,000

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	Nov. 02, 2021	Oct. 06, 2021	Sep. 29, 2021	Jul. 30, 2021	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of Class B common stock to Sponsor (in shares)					5,000,000
Sale of stock, price per share (in dollars per share)					$ 10
Private investment in public entity					$ 50,000,000
Credit facility amount											$ 65,000,000
Issuance of common stock from exercises of stock options (in shares)						2,881,000		907,000	966,000
Tax withholding and remittance obligations						$ 6,719,000	$ 0
Repayments of small business administration's paycheck protection program				$ 8,100,000
Repayments of lines of credit						38,124,000	$ 26,439,000	$ 26,439,000	$ 0	$ 0
Earnout liabilities				228,100,000		$ 266,390,000		$ 0
Subordinated Credit Facility | Line of Credit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repayments of lines of credit				$ 30,000,000
Rover Earnout Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				19,734,183		19,734,000
Earnout liabilities						$ 266,400,000
Rover Earnout Shares | Derivative Instrument, Period, One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				8,770,748
Earnout period, stock price trigger (in dollars per share)				$ 12		$ 12
Earnout period, threshold trading day period				30 days
Earnout period, threshold trading days				20 days
Rover Earnout Shares | Derivative Instrument, Period, Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				8,770,748
Earnout period, stock price trigger (in dollars per share)				$ 14		$ 14
Earnout period, threshold trading day period				30 days
Earnout period, threshold trading days				20 days
Rover Earnout Shares | Derivative Instrument, Period, Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)						2,192,687
Earnout period, stock price trigger (in dollars per share)				$ 16		$ 16
Earnout period, threshold trading day period				30 days
Earnout period, threshold trading days				20 days
Earnout liabilities						$ 28,000,000
Sponsor Earnout Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				2,461,627		492,000
Earnout shares issued (in shares)			1,969,302
Earnout liabilities			$ 33,000,000
Sponsor Earnout Shares | Derivative Instrument, Period, One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				984,651
Earnout period, stock price trigger (in dollars per share)				$ 12
Sponsor Earnout Shares | Derivative Instrument, Period, Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				984,651
Earnout period, stock price trigger (in dollars per share)				$ 14
Sponsor Earnout Shares | Derivative Instrument, Period, Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares (in shares)				492,325
Earnout period, stock price trigger (in dollars per share)			$ 16
Earnout liabilities			$ 6,300,000
Subsequent Event | Rover Earnout Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnout shares issued (in shares)		17,540,964
Subsequent Event | Restricted Stock Units (RSUs) | 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	2,827,495
Subsequent Event | Outside Directors | Restricted Stock Units (RSUs) | 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares)	115,311