CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 54,593	$ 76,015
Marketable securities (Note 4)	239,248	15,942
Contract assets	577
Prepaid expenses and other current assets	2,946	888
Total current assets	297,364	92,845
Marketable securities, non-current (Note 4)	187,464
Property and equipment, net (Note 6)	10,984	3,794
Right-of-use assets, operating leases	9,959	18,289
Other assets	1,590	1,774
Total assets	507,361	116,702
Current liabilities:
Accounts payable	3,979	3,276
Accrued expenses (Note 8)	7,874	4,568
Deferred revenue, current	92,011	23,349
Operating lease liabilities, current portion	2,733	2,696
Finance liabilities, current portion	689	681
Total current liabilities	107,286	34,570
Non-current liabilities
Deferred revenue, net of current portion	90,308	29,642
Operating lease liabilities, net of current portion	14,327	16,651
Finance lease liabilities, net of current portion	755	1,165
Total liabilities	212,676	82,028
Commitments and contingencies (Note 9)
Stockholders’ equity (deficit):
Preferred stock, $0.0001 par value; 10,000,000 and 0 shares authorized as of September 30, 2020 and December 31, 2019, respectively; 0 shares issued or outstanding as of September 30, 2020 and December 31, 2019
Common stock, $0.0001 par value; 150,000,000 and 45,000,000 shares authorized at September 30, 2020 and December 31, 2019, 44,581,051 and 2,208,982 shares issued at September 30, 2020 and December 31, 2019, respectively, and 44,447,734 and 1,929,516 shares outstanding at September 30, 2020 and December 31, 2019, respectively	4
Additional paid-in capital	410,925	2,044
Accumulated deficit	(116,080)	(76,456)
Accumulated other comprehensive (loss) income	(164)	6
Total stockholders’ equity (deficit)	294,685	(74,406)
Total liabilities, convertible preferred stock and stockholders’ equity (deficit)	$ 507,361	116,702
Series Seed Convertible Preferred Stock
Non-current liabilities
Temporary equity, value		5,900
Series A Convertible Preferred Stock
Non-current liabilities
Temporary equity, value		29,237
Series B Convertible Preferred Stock
Non-current liabilities
Temporary equity, value		59,918
Series B-1 Convertible Preferred
Non-current liabilities
Temporary equity, value		$ 14,025

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).