The components of loss before the provision for (benefit from) income taxes were as follows (in thousands):

	Year ended June 30,
	2020			2019			2018
Domestic	$	(31,038	)	$	(7,470	)	$	(7,185	)
Foreign		—			—			—
Total	$	(31,038	)	$	(7,470	)	$	(7,185	)

The components of provision for (benefit from) income taxes were as follows (in thousands):

	Year ended June 30,
	2020		2019			2018
Current:
Federal	$	—	$	—		$	—
State		53		20			10
Foreign		—		—			—
Total current		53		20			10
Deferred:		—		—			—
Federal		—		(142	)		—
State		—		(34	)		—
Foreign		—		—			—
Total current		—		(176	)		—
Provision for (benefit from) income taxes	$	53	$	(156	)	$	10

The items accounting for the difference between the income taxes computed at the federal statutory rate and the provision for (benefit from) income taxes consisted of the following (in thousands):

	Year ended June 30,
	2020			2019			2018
Expected benefit at U.S. federal statutory rate	$	(6,518	)	$	(1,569	)	$	(1,976	)
Stock-based compensation		(31,047	)		390			297
Federal and state R&D credits, net of unrecognized benefit		(6,411	)		(2,111	)		(909	)
Deferred tax asset re-measurement due to Tax Reform		—			—			12,227
Change in valuation allowance		43,716			3,029			(9,753	)
Other		313			105			124
Provision for (benefit from) income taxes	$	53		$	(156	)	$	10

The components of deferred tax assets and liabilities were as follows as of June 30, 2020 and 2019 (in thousands):

	June 30,
	2020			2019
Deferred tax assets:
Accruals and reserves	$	3,933		$	1,631
Deferred revenue		904			84
Property and equipment		128			—
Stock-based compensation		2,542			700
Net operating loss carryforwards		68,694			26,690
Research and development credits		12,226			5,649
Total deferred tax assets before valuation allowance		88,427			34,754
Valuation allowance		(85,569	)		(33,253	)
Deferred tax assets	$	2,858		$	1,501
Deferred tax liabilities:
Deferred contract costs	$	(2,182	)	$	(1,229	)
Property and equipment		—			(143	)
Other		(676	)		(129	)
Total deferred tax liabilities	$	(2,858	)	$	(1,501	)
Net deferred tax assets (liabilities)	$	—		$	—

ASC 740 requires that the tax benefit of net operating losses, temporary differences, and credit carryforwards be recorded as an asset to the extent that management assesses that realization is “more likely than not.” Realization of the future tax benefits is dependent on the Company’s ability to generate sufficient taxable income within the carryforward period. Because of the Company’s recent history of operating losses, management believes that recognition of the deferred tax assets arising from the above-mentioned future tax benefits is currently not likely to be realized and, accordingly, has provided a valuation allowance. The change in valuation allowance was approximately $52.3 million, $3.7 million and $10.0 million during the years ended June 30, 2020, 2019 and 2018, respectively, including a decrease in valuation allowance of $0.7 million related to the adoption of ASC 606 during the year ended June 30, 2018.

As of June 30, 2020, the Company had net operating loss (NOL) carryforwards of $265.8 million and $203.5 million for federal and state tax purposes, respectively, that are available to reduce future taxable income. If not utilized, the federal and state NOL carryforwards will begin to expire in 2026. As of June 30, 2020, approximately $166.0 million of federal NOL carryforwards do not expire and will carry forward indefinitely until utilized. As of June 30, 2020, the Company also had research and development tax credit carryforwards of approximately $10.6 million and $8.7 million for federal and state tax purposes, respectively. If not utilized, the federal tax credits will expire at various dates beginning in 2027. The state tax credits do not expire and will carry forward indefinitely until utilized.

Utilization of the net operating loss and tax credit carryforwards may be subject to a substantial annual limitation due to the ownership change limitations provided by the Internal Revenue Code and other similar state provisions. The annual limitation may result in the expiration of net operating losses and tax credits before utilization.

As of June 30, 2020 and 2019, the Company had $5.8 million and $2.7 million, respectively, of unrecognized tax benefits related to federal and California R&D credits. Below is the reconciliation of the unrecognized tax benefits as of the periods presented (in thousands):

	June 30,
	2020		2019		2018
Balance at the beginning of the year	$	2,692	$	1,457	$	835
Additions based upon tax positions related to the current year		3,078		1,028		—
Additions based upon tax positions related to the prior year		17		207		622
Balance at the end of the year	$	5,787	$	2,692	$	1,457

The Company files United States federal, California, and other various state income tax returns. All U.S. federal and state net operating losses and tax credits generated to date are subject to adjustments. The Company does not anticipate any material change to its unrecognized tax benefits over the next twelve months. The Company’s U.S. federal and state tax returns remain subject to examination by taxing authorities. The tax years from 2006 to 2019 remain open as a result of unused tax attributes being carried forward.