0001628280-21-009745 | 10-Q | XBRL Viewer

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Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2021	May 05, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-39747
Entity Registrant Name	SEER, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-1153150
Entity Address, Address Line One	3800 Bridge Parkway
Entity Address, Address Line Two	Suite 102
Entity Address, City or Town	Redwood City
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94065
City Area Code	650
Local Phone Number	453-0000
Title of 12(b) Security	Common Stock, par value $0.00001
Trading Symbol	SEER
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	false
Entity Central Index Key	0001726445
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Ex Transition Period	false
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		56,630,310
Class B common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		4,702,381

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 445,763	$ 333,585
Investments	85,379	98,278
Inventory	1,541	551
Other receivables	412	163
Other receivables, related parties	101	99
Prepaid expenses and other current assets	3,041	452
Total current assets	536,237	433,128
Property and equipment, net	8,682	8,441
Restricted cash	343	343
Other assets	377	407
Total assets	545,639	442,319
Current liabilities:
Accounts payable	1,933	2,115
Accrued expenses	4,201	5,147
Accrued research and development	820	396
Deferred revenue	256	250
Deferred rent, current	186	186
Total current liabilities	7,396	8,094
Deferred rent, net of current portion	1,884	1,899
Other noncurrent liabilities	589	717
Total liabilities	9,869	10,710
Commitments
Stockholders’ equity:
Preferred stock, $0.00001 par value; 5,000,000 shares authorized as of March 31, 2021 and December 31, 2020; zero shares issued and outstanding as of March 31, 2021 and December 31, 2020	0	0
Additional paid-in capital	607,531	486,915
Accumulated other comprehensive income	28	54
Accumulated deficit	(71,790)	(55,361)
Total stockholders’ equity	535,770	431,609
Total liabilities and stockholders’ equity	545,639	442,319
Class A common stock
Stockholders’ equity:
Common stock	1	1
Class B common stock
Stockholders’ equity:
Common stock	$ 0	$ 0

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Preferred stock, par value (in usd per share)	$ 0.00001	$ 0.00001
Preferred stock, authorized (in shares)	5,000,000	5,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, authorized (in shares)	105,000,000
Common stock, issued (in shares)	61,309,349	59,261,051
Common stock, outstanding (in shares)	61,309,349	59,261,051
Class A common stock
Common stock, par value (usd per share)	$ 0.00001	$ 0.00001
Common stock, authorized (in shares)	94,000,000	94,000,000
Common stock, issued (in shares)	56,606,968	53,395,319
Common stock, outstanding (in shares)	56,606,968	53,395,319
Class B common stock
Common stock, par value (usd per share)	$ 0.00001	$ 0.00001
Common stock, authorized (in shares)	6,000,000	6,000,000
Common stock, issued (in shares)	4,702,381	5,865,732
Common stock, outstanding (in shares)	4,702,381	5,865,732

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue:
Grant revenue	$ 62	$ 177
Operating expenses:
Research and development	6,227	4,222
Selling, general and administrative	10,333	1,780
Total operating expenses	16,560	6,002
Loss from operations	(16,498)	(5,825)
Other income (expense):
Interest income	69	332
Total other income (expense)	69	332
Net loss	(16,429)	(5,493)
Other comprehensive loss:
Unrealized gain (loss) on available-for-sale securities	(26)	533
Comprehensive loss	$ (16,455)	$ (4,960)
Net loss per share available to common shareholders, diluted (in usd per share)	$ (0.27)	$ (0.61)
Net loss per share available to common shareholders, basic (in usd per share)	$ (0.27)	$ (0.61)
Weighted average number of shares outstanding, diluted (in shares)	59,887,842	8,944,284
Weighted-average common shares outstanding, basic (in shares)	59,887,842	8,944,284
Revenue, Product and Service [Extensible List]	us-gaap:GrantMember	us-gaap:GrantMember

Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Total	IPO	Follow On Offering	Convertible Preferred Stock Preferred Class A	Class A and Class B Common Stock	Class A and Class B Common Stock IPO	Class A and Class B Common Stock Follow On Offering	Additional Paid in Capital	Additional Paid in Capital IPO	Additional Paid in Capital Follow On Offering	Accumulated Deficit	Accumulated Other Comprehensive Income
Beginning balance at Dec. 31, 2019	$ 87,679			$ 107,953	$ 0			$ 2,288			$ (22,586)	$ 24
Beginning balance (in shares) at Dec. 31, 2019				22,173,216	12,193,677
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock (in shares)						40,207
Issuance of Class A common stock		$ 24							$ 24
Vesting of early exercised stock options and restricted common stock	4							4
Stock-based compensation	579							579
Other comprehensive income	533											533
Net loss	(5,493)										(5,493)
Ending balance at Mar. 31, 2020	83,326			$ 107,953	$ 0			2,895			(28,079)	557
Ending balance (in shares) at Mar. 31, 2020				22,173,216	12,233,884
Beginning balance at Dec. 31, 2020	$ 431,609			$ 0	$ 1			486,915			(55,361)	54
Beginning balance (in shares) at Dec. 31, 2020	59,261,051			0	59,261,051
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock (in shares)						399,174	1,650,000
Issuance of Class A common stock		$ 171	$ 102,959						$ 171	$ 102,959
Repurchase of Class A common stock (in shares)					(876)
Repurchase of Class A common stock	$ 0
Vesting of early exercised stock options and restricted common stock	44							44
Return of profit	11,403							11,403
Stock-based compensation	6,039							6,039
Other comprehensive income	(26)											(26)
Net loss	(16,429)										(16,429)
Ending balance at Mar. 31, 2021	$ 535,770			$ 0	$ 1			$ 607,531			$ (71,790)	$ 28
Ending balance (in shares) at Mar. 31, 2021	61,309,349			0	61,309,349

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
OPERATING ACTIVITIES
Net loss	$ (16,429)	$ (5,493)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	6,039	579
Depreciation and amortization	482	277
Net amortization of premium on available-for-sale securities	152	46
Changes in operating assets and liabilities:
Other receivables	(249)	(112)
Other receivables - related parties	(2)	0
Prepaid expenses and other current assets	(2,589)	(106)
Inventory	(990)	0
Other assets	30	(79)
Accounts payable	(234)	481
Deferred revenue	6	0
Deferred rent	(15)	166
Accrued expenses	(1,414)	(885)
Accrued research and development	424	52
Other noncurrent liabilities	(83)	0
Net cash used in operating activities	(14,872)	(5,074)
INVESTING ACTIVITIES
Purchases of property and equipment	(838)	(1,063)
Purchase of available-for-sale securities	(30,279)	(3,485)
Proceeds from maturities of available-for-sale securities	43,000	7,500
Net cash provided by investing activities	11,883	2,952
FINANCING ACTIVITIES
Proceeds from issuance of common stock upon follow-on public offering, net of issuance costs	103,595	0
Proceeds from return of profit	11,403	0
Repurchase of Class A common stock	(2)	0
Proceeds from stock option exercises including early exercised options	171	45
Net cash provided by financing activities	115,167	45
Net increase (decrease) in cash, cash equivalents and restricted cash	112,178	(2,077)
Cash, cash equivalents and restricted cash, beginning of period	333,928	17,828
Cash, cash equivalents and restricted cash, end of period	446,106	15,751
Accounts Payable
FINANCING ACTIVITIES
Property and equipment purchases included in balance sheet locations	9	2,424
Offering costs in accounts payable	158	0
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Property and equipment purchases included in balance sheet locations	9	2,424
Offering costs in accounts payable	158	0
Accrued Liabilities
FINANCING ACTIVITIES
Property and equipment purchases included in balance sheet locations	49	0
Offering costs in accounts payable	478	0
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Property and equipment purchases included in balance sheet locations	49	0
Offering costs in accounts payable	$ 478	$ 0

Condensed Consolidated Statements of Equity (Parentheticals) - USD ($) $ in Thousands		3 Months Ended
	Feb. 01, 2021	Mar. 31, 2021	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Offering transaction costs	$ 7,600	$ 7,591
Stock-based compensation		$ 6,039	$ 579

Organization and Description of the Business	3 Months Ended
Organization and Description of the Business	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of the Business	ORGANIZATION AND DESCRIPTION OF THE BUSINESS Seer, Inc. (the Company) was incorporated in Delaware on March 16, 2017, and is based in Redwood City, California. In December 2020, the Company formed the wholly-owned subsidiary, Seer Securities Corporation, located in Massachusetts. The Company is a life sciences company focused on capturing deep molecular insights from the proteome to enable novel insights and breakthroughs in the understanding of biology and disease. Since inception, the Company has devoted its efforts principally to research and development of its technology and product candidates, recruiting management and technical staff, acquiring operating assets, and raising capital. The Company is subject to a number of risks, similar to other early-stage life science companies, including, but not limited to, development and commercialization of its products, market acceptance of its products, development by its competitors of new technological innovations, protection of its intellectual property, and raising additional capital. Public Offering On February 1, 2021, the Company completed an underwritten public offering of 1,650,000 shares of its Class A common stock at a public offering price of $67.00 per share. The Company received net proceeds of $103.0 million after deducting offering costs, underwriting discounts, and commissions of $7.6 million. Reverse Stock Split In November 2020, the Company’s board of directors approved an amended and restated certificate of incorporation to effect a reverse split of shares of the Company’s common stock and convertible preferred stock on a 1-for-2.14 basis (the Reverse Stock Split) effective as of November 25, 2020. The par values of the common stock and convertible preferred stock were not adjusted as a result of the Reverse Stock Split. All references to common stock, options to purchase common stock, restricted stock awards, restricted stock units, convertible preferred stock, share data, per share data, and related information contained in the unaudited condensed consolidated financial statements have been retrospectively adjusted to reflect the effect of the Reverse Stock Split for all periods presented. Liquidity As of March 31, 2021, the Company has incurred significant losses and has had negative cash flows from operations. As of March 31, 2021, the Company had cash, cash equivalents and investments of $531.1 million and an accumulated deficit of $71.8 million. Management expects to continue to incur significant expenses for the foreseeable future and to incur operating losses in the near term while the Company makes investments to support its anticipated growth. The Company believes that its cash and cash equivalents balance as of March 31, 2021 provides sufficient capital resources to continue its operations for at least 12 months from the issuance date of the accompanying unaudited condensed consolidated financial statements.

Summary of Significant Accounting Policies and Basis of Presentation

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies and Basis of Presentation

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND BASIS OF PRESENTATION

Basis of Presentation

The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP). The Company has issued shares of Class A common stock, herein referred to as “Class A common stock” or “Class A,” and Class B common stock, herein referred to as “Class B common stock” or “Class B,” and collectively as “common stock.” The unaudited condensed consolidated financial statements include the accounts of Seer, Inc. and its wholly-owned subsidiary. All intercompany transactions and balances have been eliminated.

The condensed consolidated balance sheets at December 31, 2020 have been derived from the audited consolidated financial statements of the Company at that date. Certain information and footnote disclosures typically included in the Company’s audited consolidated financial statements have been condensed or omitted. The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include

only normal recurring adjustments, necessary to state fairly the Company’s financial position, results of operations, comprehensive loss and cash flows for the periods presented, but are not necessarily indicative of the results of operations to be anticipated for any future annual or interim period.

The accompanying unaudited condensed consolidated financial statements and notes should be read in conjunction with the audited consolidated financial statements and related notes for the year ended December 31, 2020 included in the Annual Report on Form 10-K filed with the SEC on March 29, 2021.

Use of Estimates

The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates and assumptions, including, but not limited to, those related to the fair value of common stock, stock-based compensation, accrued research and development expenses, useful lives and valuation of property and equipment, income tax uncertainties, and tax valuation allowances.

Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from those estimates.

Impact of the COVID-19 Pandemic

As a result of the COVID-19 pandemic (COVID-19), the Company’s operations experienced disruptions and restrictions on employees’ ability to work and on the hiring of additional personnel, particularly as a result of preventive and precautionary measures taken by the Company and some of its suppliers and other service providers. In particular, some of the Company’s laboratory material and equipment suppliers, collaborators, and service providers used in the performance of its research activities and phased commercial launch plan have been similarly impacted by COVID-19, which may limit the Company’s ability to achieve its planned progress. COVID-19 has adversely affected the broader economy, which could affect the Company’s financing prospects. Continued disruptions from COVID-19 could harm the Company’s operations and the Company cannot anticipate all the ways in which it could be adversely impacted by health epidemics such as COVID-19.

The COVID-19 pandemic has mainly impacted the progress of research and development activities due to the limited ability of the Company’s employees to access laboratories during times of statewide quarantine and on some of its suppliers who have experienced a surge in demand for their products resulting in supply delays for critical hardware, instrumentation and medical and testing supplies used for product development. The Company continues to monitor and assess the effects of the COVID-19 pandemic on its business, financial condition, results of operations and cash flows.

Cash, Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. As of March 31, 2021 and December 31, 2020, all amounts recorded as cash and cash equivalents consist of money market funds and are stated at fair value.

Restricted cash as of March 31, 2021 and December 31, 2020 represents cash held by a financial institution as security for a letter of credit issued to the lessor for one of the Company’s operating leases and is classified as non-current.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the unaudited condensed consolidated balance sheets that sum to the total of the same amounts shown in the unaudited condensed consolidated statements of cash flows (in thousands):


	March 31,		December 31,
	2021		2020

Cash and cash equivalents	$	445,763	$	333,585
Restricted cash	343		343
Total cash, cash equivalents and restricted cash	$	446,106	$	333,928

Revenue Recognition

Research Revenue

The Company recognizes revenue when control of the services is transferred to its customers in an amount that reflects the consideration it expects to receive from its customers in exchange for those services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers a performance obligation satisfied once it has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service.

The Company recognizes revenue for research and development services contracts when control is transferred, which is upon completion of the services and when results of the services have been transferred to the customer. Upfront payments and fees received are recorded as deferred revenue until the Company performs its obligations under its arrangements. Amounts payable to the Company are recorded as other receivables when its right to consideration is unconditional. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised goods or services to the customer will be one year or less.

Grant Revenue

Grant revenue represents funding under cost reimbursement programs from federal foundation sources for qualified research and development activities performed by the Company and are not based on estimates that are subject to change. Grants received are assessed to determine if the agreement should be accounted for as an exchange transaction or a contribution. An agreement is accounted for as a contribution if the resource provider does not receive commensurate value in return for the assets transferred. Such amounts are recorded as revenue as grant-funded activities are performed up to the amount of expenses incurred. Any advance funding payments are recorded as deferred revenue until the activities are performed.

Stock-Based Compensation

The Company accounts for stock-based compensation, including from restricted common stock awards (RSAs), grants of restricted stock units (RSUs), and stock options that may be settled in shares of our common stock, based on the fair values of the equity instruments issued. The fair value is determined on the measurement date, which is generally the date of grant. The fair value of RSAs is the difference between the fair value of the underlying stock at the measurement date and the purchase price. The fair value of RSUs is the fair value of the underlying stock at the measurement date. The fair value for our stock option awards is determined at the grant date using the Black-Scholes valuation model. The fair value of share-based payment awards is recognized as expense on a straight-line basis over the requisite service period in which the awards are expected to vest. Forfeitures are accounted for in the period in which they occur. Share-based payment awards that include a service condition and a performance condition are expected to vest when the performance condition is probable of being met.

The Black-Scholes model considers several variables and assumptions in estimating the fair value of stock-based awards that require judgment, for which changes if they occur can materially affect the resulting estimates of fair value. These assumptions include the per share fair value of the underlying common stock, exercise price, expected term, risk-free interest rate, expected annual dividend yield, and the expected stock price volatility over the expected term as follows:

Fair Value of Common Stock

For grants prior to the Company’s IPO in December 2020, the grant-date fair market value of the shares of common stock underlying stock options was determined by the Company’s Board of Directors with assistance of third-party valuation specialists. Because there has been no public market for the Company’s common stock, the Board of Directors exercises reasonable judgment and considers a number of objective and subjective factors to determine the best estimate of the fair market value, which include important developments in the Company’s operations, the prices at which the Company sold shares of its convertible preferred stock, the rights, preferences and privileges of the Company’s convertible preferred stock relative to those of the Company’s common stock, actual operating results, financial performance, external market conditions in the life sciences industry, general U.S. market conditions, equity market conditions of comparable public companies, and the lack of marketability of the Company’s common stock. For all grants subsequent to the IPO, the fair value of common stock was determined by using the closing price per share of common stock as reported on the Nasdaq Global Select Market.

Expected Volatility

The Company had no publicly available stock price information prior to its IPO and limited publicly available stock price information subsequent to its IPO and therefore the Company has used the historical volatility of the stock price of similar publicly traded peer companies. The historical volatility is calculated based on a period of time commensurate with the expected term assumptions.

Expected Term

For stock options granted to employees and directors, the expected term is calculated using the simplified method for “plain vanilla” stock option awards. The expected term for stock options granted to non-employees is the contractual term.

Risk-Free Interest Rate

The risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues similar in duration to the expected term of the equity-settled award.

Expected Dividends

The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay dividends on its common stock.

Net Loss Per Share Attributable to Common Stockholders

Net loss per share of common stock is computed using the two-class method required for multiple classes of common stock and participating securities based upon their respective rights to receive dividends as if all income for the period has been distributed. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders is therefore the same for Class A and Class B common stock on an individual or combined basis.

The Company’s participating securities include the Company’s convertible preferred stock, as the holders are entitled to receive noncumulative dividends on a pari passu basis in the event that a dividend is paid on common stock. The Company also considers any shares issued on the early exercise of stock options subject to repurchase to be participating securities because holders of such shares have non-forfeitable dividend rights in the event a dividend

is paid on common stock. The holders of convertible preferred stock, as well as the holders of early exercised shares subject to repurchase, do not have a contractual obligation to share in losses.

Basic net loss per share attributable to common stockholders 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, adjusted for outstanding shares that are subject to repurchase.

Diluted net loss per share is computed by giving effect to all potentially dilutive securities outstanding for the period using the treasury stock method or the if-converted method based on the nature of such securities. For periods in which the Company reports net losses, diluted net loss per common share attributable to common stockholders is the same as basic net loss per common share attributable to common stockholders, because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

Recently Adopted Accounting Pronouncements

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which is intended to simplify the accounting for income taxes. This standard removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing standards to improve consistent application. The Company adopted this standard as of January 1, 2021, which did not have a material impact on its financial statements as of the adoption date.

In January 2020, the FASB issued ASU No. 2020-01, Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815). This standard clarifies the interaction between accounting standards related to equity securities, equity method investments, and certain derivative instruments. The Company adopted this standard as of January 1, 2021, which did not have a material impact on its financial statements as of the adoption date.

Recently Issued Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This standard clarifies the definition of a lease and requires a lessee to recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-to-use asset representing its right to use the underlying asset for the lease term. In November 2019, the FASB issued ASU No. 2019-10 which extends the effective date of ASU No. 2016-02 for non-public business entities, including smaller reporting companies, to fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022. While the Company has not yet quantified the impact, these adjustments will increase total assets and total liabilities relative to such amounts reported prior to adoption.

Fair Value Measurements and Fair Value of Financial Instruments

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements and Fair Value of Financial Instruments

FAIR VALUE MEASUREMENTS AND FAIR VALUE OF FINANCIAL INSTRUMENTS

The following tables set forth the fair value of the Company’s financial assets that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands).


		March 31, 2021
		Level 1		Level 2		Level 3		Total
Assets:	Classification:
Money market funds	Cash and cash equivalents	$	444,668	$	—	$	—	$	444,668
U.S. Treasury securities	Investments	—		85,379		—		85,379
Total assets measured at fair value		$	444,668	$	85,379	$	—	$	530,047


		December 31, 2020
		Level 1		Level 2		Level 3		Total
Assets:	Classification:
Money market funds	Cash and cash equivalents	$	333,585	$	—	$	—	$	333,585
U.S. Treasury securities	Investments	—		98,278		—		98,278
Total assets measured at fair value		$	333,585	$	98,278	$	—	$	431,863

There were no financial liabilities measured at fair value. The Company classifies money market funds within Level 1 of the fair value hierarchy because they are valued using bank balances or quoted market prices. The Company classifies its investments in U.S. Treasury securities (Treasury bills, Treasury notes, and Treasury bonds) as Level 2 instruments and obtains fair value from an independent pricing service, which may use quoted market prices for identical or comparable instruments or model-driven valuations using observable market data or inputs corroborated by observable market data.

The carrying amount of the Company’s other receivables, prepaid expenses, other current assets, accounts payable, and accrued expenses approximate fair value due to their short maturities.

The following is a summary of the Company’s cash equivalents and investments and the gross unrealized holding gains and losses (in thousands):


	March 31, 2021
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses		Fair Value
Assets:
Money market funds	$	444,668	$	—	$	—	$	444,668
U.S. Treasury securities	85,351		28		—		85,379
Total	$	530,019	$	28	$	—	$	530,047


	December 31, 2020
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses		Fair Value
Assets:
Money market funds	$	333,585	$	—	$	—	$	333,585
U.S. Treasury securities	98,223		57		(2)		98,278
Total	$	431,808	$	57	$	(2)	$	431,863

As of December 31, 2020, unrealized losses on available-for-sale investments are not attributable to credit risk and are considered to be temporary. The Company believes it is more likely than not that investments in an unrealized loss position will be held until maturity or the recovery of the cost basis of the investment. There were no

unrealized losses on available-for-sale investments as of March 31, 2021. To date, the Company has not recorded any impairment charges on marketable securities related to other-than-temporary declines in market value. As of March 31, 2021 and December 31, 2020, the weighted-average remaining maturity of the Company’s investment portfolio was less than one year.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Other Financial Statement Information

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Other Financial Statement Information

OTHER FINANCIAL STATEMENT INFORMATION

Inventory

Inventory consists of the following (in thousands):


	March 31,		December 31,
	2021		2020

Raw materials	$	622	$	—
Finished goods	919		551
Total inventory	$	1,541	$	551

Other Receivables

Other receivables consist of the following (in thousands):


	March 31,		December 31,
	2021		2020

Interest receivable	$	335	$	120
Other	178		142
Total other receivables	$	513	$	262

Property and Equipment, Net

Property and equipment, net consists of the following (in thousands):


	March 31,		December 31,
	2021		2020

Laboratory equipment	$	8,774	$	8,075
Computer equipment and software	206		182
Furniture and fixtures	241		241
Leasehold improvements	2,294		2,294
Property and equipment	11,515		10,792
Less: accumulated depreciation and amortization	2,833		2,351
Total property and equipment, net	$	8,682	$	8,441

Depreciation and amortization expense related to property and equipment was $0.5 million and $0.3 million for the three months ended March 31, 2021 and 2020, respectively.

Accrued Expenses

Accrued expenses consist of the following (in thousands):


	March 31,		December 31,
	2021		2020

Accrued compensation	$	1,446	$	2,866
Accrued professional services	1,314		1,074
Restricted stock liability, current	483		484
Other	958		723
Total accrued expenses	$	4,201	$	5,147

Revenue and Deferred Revenue	3 Months Ended
Revenue and Deferred Revenue	Mar. 31, 2021
Revenue Recognition and Deferred Revenue [Abstract]
Revenue from Contract with Customer	REVENUE AND DEFERRED REVENUE As of March 31, 2021 and December 31, 2020, the Company recorded $0.3 million and $0.3 million of deferred revenue related to the following agreements. Research Agreements In February 2019, the Company entered into a sponsored research agreement with a biotechnology company under which the Company is required to execute certain research and development activities as well as optional research and development activities if elected by the customer for total consideration payable of $0.4 million. During the three months ended March 31, 2021 and 2020, the Company did not recognize any research revenue with respect to this agreement. In March 2020, the Company entered into a sponsored research agreement with a pharmaceutical company under which the Company is required to execute certain research and development activities for total consideration payable of $0.5 million, of which $0.3 million was received and recorded as deferred revenue as of March 31, 2021. During the three months ended March 31, 2021 and 2020, the Company did not recognize any research revenue with respect to the research agreement. NIH Grant In August 2019, the Company received a notice of a Small Business Innovation Research grant award from the National Institutes of Health, which will provide funding of approximately $1.1 million to the Company for its development of research applications. In June 2020, the Company received a notice that additional grant consideration of $0.9 million will be awarded. During the three months ended March 31, 2021 and 2020, the Company recognized grant revenue of $0.1 million and $0.2 million, respectively, with respect to the award.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Capital Stock and Stockholders' Equity

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

Capital Stock and Stockholders' Equity

CAPITAL STOCK AND STOCKHOLDERS’ EQUITYAs of March 31, 2021, the Company is authorized to issue 105,000,000 shares of capital stock consisting of 94,000,000 shares of Class A common stock, 6,000,000 shares of Class B common stock, and 5,000,000 shares of preferred stock.

Common Stock

Common stock issued and outstanding is as follows:


	March 31,	December 31,
	2021	2020

Class A common stock	56,606,968	53,395,319
Class B common stock	4,702,381	5,865,732
Total common stock issued and outstanding	61,309,349	59,261,051

Class A and Class B common stock have a par value of $0.00001 per share. Holders of Class A common stock are entitled to one vote per share and holders of Class B common stock are entitled to 10 votes per share. Class B common shares are convertible to Class A common shares at any time at the option of the holder on a one-for-one basis. Holders of common stock are entitled to dividends as declared by the Board of Directors, subject to rights of holders of all classes of stock outstanding having priority rights as to dividends. There have been no dividends declared to date.

In the first quarter of 2021, the Company received $11.4 million related to the return of short-swing profits from one of its beneficial owners. These proceeds are recognized as a capital contribution from stockholders as an increase to additional paid-in capital on the condensed consolidated statements of changes in stockholders’ equity and as cash provided by financing activities on the condensed consolidated statements of cash flows.

Equity Incentive Plans

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Equity Incentive Plans

EQUITY INCENTIVE PLANS

In 2017, the Company adopted the 2017 Stock Incentive Plan (2017 Plan), which provided for the granting of awards to employees, directors, and consultants of the Company. Awards issuable under the Plan include incentive stock options (ISO), nonqualified stock options (NSO), and restricted stock awards. In 2020, the Company adopted the 2020 RSU Equity Incentive Plan (2020 RSU Plan), which provided for the granting of RSUs to certain employees of the Company.

In 2020, the Company adopted the 2020 Equity Incentive Plan (2020 Plan), which became effective in connection with the IPO. The Company’s 2017 Plan and 2020 RSU Plan were terminated in connection with the IPO and no further grants will be made under the 2017 Plan and 2020 RSU Plan from the date that the 2020 Plan became effective.

As of March 31, 2021, there are 8,302,701 shares of Class A common stock reserved for issuance under the 2020 Plan of which 6,153,968 shares are available for issuance in connection with grants of future awards.

Stock option activity for the three months ended March 31, 2021 is as follows:


	Options Outstanding	Weighted Average Exercise Price
Balance - December 31, 2020	9,551,105	$	5.55
Options granted	768,624	59.94
Options exercised	(399,174)	0.44
Options cancelled and forfeited	(81,201)	5.70
Balance - March 31, 2021	9,839,354	$	10.00
Vested and exercisable, March 31, 2021	1,616,370	$	2.44

Restricted Stock

Certain stock options granted under the 2017 Plan provide stock option holders the right to exercise unvested stock options in exchange for restricted shares of Class A common stock. The Company has also issued restricted shares of Class A common stock to employees and directors under the 2017 Plan.

The activity of restricted shares of Class A common stock for the three months ended March 31, 2021 is as follows:


	Number of Shares	Weighted-Average Grant Date Fair Value
Unvested at December 31, 2020	775,641	$	1.77
Granted	10,728	1.66
Repurchased	(876)	1.55
Vested	(133,075)	2.07
Unvested at March 31, 2021	652,418	$	1.71

RSUs

The Company has granted RSUs under the 2020 RSU Plan and the 2020 Plan. RSU activity for the three months ended March 31, 2021 is as follows:


	Restricted Stock Units	Weighted-Average Grant Date Fair Value
Balance at December 31, 2020	491,318	$	7.91
Granted	200,233	60.06
Vested	(1,120)	34.35
Cancelled	(947)	19.00
Balance at March 31, 2021	689,484	$	23.05

Employee Stock Purchase Plan

In November 2020, the Company’s board of directors adopted the 2020 Employee Stock Purchase Plan (ESPP), which was subsequently approved by the Company’s stockholders and became effective in connection with the IPO. A total of 1,195,327 shares of Class A common stock are reserved for issuance under the ESPP as of March 31, 2021. The first offering period has not commenced as of March 31, 2021 and there is no stock-based compensation related to the ESPP for the three months ended March 31, 2021.

Stock-Based Compensation

The following table summarizes the components of stock-based compensation recognized in the Company’s condensed consolidated statements of operations and comprehensive loss (in thousands):


	Three Months Ended March 31,
	2021		2020

Research and development	$	1,492	$	182
Selling, general and administrative	4,547		397
Total stock-based compensation	$	6,039	$	579

Commitments

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments

COMMITMENTS

Facility Lease Agreement

On January 4, 2019, the Company entered into a lease agreement for office and laboratory space in Redwood City, California. The lease term commenced in November 2019 and ends on September 30, 2029. In connection with the lease, the Company maintains a letter of credit issued to the lessor in the amount of $0.3 million, which is secured by restricted cash that is classified as non-current at March 31, 2021 and December 31, 2020 based on the term of the underlying lease.

The Company entered into an amendment to the lease agreement with respect to its facility in Redwood City, California in June 2020. The amendment is accounted for as a new operating lease. The amendment makes certain changes to the original lease, including (i) additional office and laboratory space in the same building (Expansion Premises) and (ii) an extension of the expiration date of the original lease to 127.5 months following the delivery date of the Expansion Premises, which is estimated to be in the fourth quarter of 2021.

The amendment provides for annual base rent for the Expansion Premises of approximately $0.9 million in the first year of the lease term (subject to an abatement period of nine months), which increases on an annual basis to approximately $1.2 million in the final year of the lease term. The amendment also provides for tenant incentives in the amount of $2.4 million. Under the amendment, the Company retains its original option to renew the lease for an additional five-year term, at then-current market rates.

During the period from the lease amendment commencement until the earlier of one month after occupancy of the Expansion Premises or September 2021, the Company will be provided with temporary space. The Company is not required to pay additional rent for the temporary space, but is required to pay property taxes, insurance and normal maintenance costs with respect to the temporary space.

Rent expense was $0.2 million and $0.2 million for the three months ended March 31, 2021 and 2020, respectively. The Company is required to pay property taxes, insurance, and normal maintenance costs for the facility and will be required to pay any increases over the base year of these expenses.

As of March 31, 2021, future minimum commitments under the Company’s non-cancelable facility operating lease are as follows:


Years ending December 31,	(in thousands)
2021 (nine months remaining)	$	596
2022	1,279
2023	1,783
2024	1,833
2025	1,884
Thereafter	13,178
Total	$	20,553

The above table does not include the amendment to the existing operating lease we entered into in April 2021. See Note 11.

Purchase Commitments and Obligations

The Company has certain purchase commitments related to its inventory management with certain manufacturing suppliers wherein the Company is required to purchase the amounts forecasted in a blanket purchase order within a certain time period. The contractual obligations represent future cash commitments and liabilities under agreements with third parties and exclude orders for goods and services entered into in the normal course of business that are not enforceable or subject to change. These outstanding commitments amounted to $4.6 million and $3.1 million as of March 31, 2021 and December 31, 2020, respectively, and are excluded from the future minimum commitments table above.

Guarantees and Indemnifications

In the normal course of business, the Company enters into agreements that contain a variety of representations and provide for general indemnification. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future. The Company has entered into indemnification agreements with certain directors and officers that require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of the status or service as directors or officers. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. As of March 31, 2021 and December 31, 2020, the Company does not have any material indemnification claims that were probable or reasonably possible and consequently has not recorded related liabilities.

Contingencies

From time to time, the Company may become involved in legal proceedings arising in the ordinary course of business. The Company is not currently a party to any material legal proceedings.

Prognomiq, Inc.	3 Months Ended
Prognomiq, Inc.	Mar. 31, 2021
Business Combinations [Abstract]
Prognomiq, Inc.	PROGNOMIQ, INC. In August 2020, the Company formed a new entity, PrognomIQ, Inc. (PrognomIQ), and entered into a stock purchase agreement with PrognomIQ, pursuant to which the Company transferred to PrognomIQ certain assets that comprise the Company’s human diagnostics activities in exchange for all the outstanding equity interests of PrognomIQ. The Company subsequently completed a pro-rata distribution to its stockholders of most of the shares of capital stock of PrognomIQ. The Company has concluded that PrognomIQ is a VIE due to its reliance on future financing and insufficient equity investment at risk. However, the Company is not the primary beneficiary of the VIE as it does not have the power to direct the activities that most significantly impact the economic performance of PrognomIQ and does not have control over the PrognomIQ board of directors. The Company has determined that it has the ability to exercise significant influence over PrognomIQ and therefore has accounted for its investment in PrognomIQ using the equity method. During the year ended December 31, 2020, the carrying value of the Company’s investment in PrognomIQ was reduced to nil after recognizing net losses based on its percentage of ownership in PrognomIQ. PrognomIQ constitutes a related party and, as of March 31, 2021 and December 31, 2020, the Company recorded $0.1 million and $0.1 million in other receivables, related parties, respectively, on the condensed consolidated balance sheets representing amounts due for general transition services and support provided.

Net Loss Per Share Attributable To Common Stockholders

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Net Loss Per Share Attributable To Common Stockholders

NET LOSS PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS

The following table shows the computation of basic and diluted net loss per share (in thousands, except share and per share data):


	Three Months Ended March 31,
	2021		2020

Numerator:
Net loss attributable to common stockholders	$	(16,429)	$	(5,493)
Denominator:
Weighted-average common shares used in computing net loss per share attributable to common stockholders, basic and diluted	59,887,842		8,944,284
Net loss per share attributable to common stockholders, basic and diluted	$	(0.27)	$	(0.61)

The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been anti-dilutive (on an as-converted basis):


	March 31,
	2021	2020

Convertible preferred stock	—	22,173,216
Class A common stock options issued and outstanding	9,839,354	5,701,527
Restricted common stock subject to future vesting	652,418	2,836,759
Restricted stock units	689,484	—
Total	11,181,256	30,711,502

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTSIn April 2021, the Company entered into an amendment to its existing operating lease agreement expanding its current office and laboratory facilities by approximately 25,000 square feet for approximately $160,000 per month plus operating expenses. The lease has a term of approximately 11 years years and commences in May 2021.

Summary of Significant Accounting Policies and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP). The Company has issued shares of Class A common stock, herein referred to as “Class A common stock” or “Class A,” and Class B common stock, herein referred to as “Class B common stock” or “Class B,” and collectively as “common stock.” The unaudited condensed consolidated financial statements include the accounts of Seer, Inc. and its wholly-owned subsidiary. All intercompany transactions and balances have been eliminated. The condensed consolidated balance sheets at December 31, 2020 have been derived from the audited consolidated financial statements of the Company at that date. Certain information and footnote disclosures typically included in the Company’s audited consolidated financial statements have been condensed or omitted. The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position, results of operations, comprehensive loss and cash flows for the periods presented, but are not necessarily indicative of the results of operations to be anticipated for any future annual or interim period.
Use of Estimates	Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates and assumptions, including, but not limited to, those related to the fair value of common stock, stock-based compensation, accrued research and development expenses, useful lives and valuation of property and equipment, income tax uncertainties, and tax valuation allowances. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from those estimates.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. As of March 31, 2021 and December 31, 2020, all amounts recorded as cash and cash equivalents consist of money market funds and are stated at fair value. Restricted cash as of March 31, 2021 and December 31, 2020 represents cash held by a financial institution as security for a letter of credit issued to the lessor for one of the Company’s operating leases and is classified as non-current.
Revenue Recognition	Revenue Recognition Research Revenue The Company recognizes revenue when control of the services is transferred to its customers in an amount that reflects the consideration it expects to receive from its customers in exchange for those services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers a performance obligation satisfied once it has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The Company recognizes revenue for research and development services contracts when control is transferred, which is upon completion of the services and when results of the services have been transferred to the customer. Upfront payments and fees received are recorded as deferred revenue until the Company performs its obligations under its arrangements. Amounts payable to the Company are recorded as other receivables when its right to consideration is unconditional. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the customer and the transfer of the promised goods or services to the customer will be one year or less. Grant Revenue Grant revenue represents funding under cost reimbursement programs from federal foundation sources for qualified research and development activities performed by the Company and are not based on estimates that are subject to change. Grants received are assessed to determine if the agreement should be accounted for as an exchange transaction or a contribution. An agreement is accounted for as a contribution if the resource provider does not receive commensurate value in return for the assets transferred. Such amounts are recorded as revenue as grant-funded activities are performed up to the amount of expenses incurred. Any advance funding payments are recorded as deferred revenue until the activities are performed.
Stock-based Compensation	Stock-Based Compensation The Company accounts for stock-based compensation, including from restricted common stock awards (RSAs), grants of restricted stock units (RSUs), and stock options that may be settled in shares of our common stock, based on the fair values of the equity instruments issued. The fair value is determined on the measurement date, which is generally the date of grant. The fair value of RSAs is the difference between the fair value of the underlying stock at the measurement date and the purchase price. The fair value of RSUs is the fair value of the underlying stock at the measurement date. The fair value for our stock option awards is determined at the grant date using the Black-Scholes valuation model. The fair value of share-based payment awards is recognized as expense on a straight-line basis over the requisite service period in which the awards are expected to vest. Forfeitures are accounted for in the period in which they occur. Share-based payment awards that include a service condition and a performance condition are expected to vest when the performance condition is probable of being met. The Black-Scholes model considers several variables and assumptions in estimating the fair value of stock-based awards that require judgment, for which changes if they occur can materially affect the resulting estimates of fair value. These assumptions include the per share fair value of the underlying common stock, exercise price, expected term, risk-free interest rate, expected annual dividend yield, and the expected stock price volatility over the expected term as follows: Fair Value of Common Stock For grants prior to the Company’s IPO in December 2020, the grant-date fair market value of the shares of common stock underlying stock options was determined by the Company’s Board of Directors with assistance of third-party valuation specialists. Because there has been no public market for the Company’s common stock, the Board of Directors exercises reasonable judgment and considers a number of objective and subjective factors to determine the best estimate of the fair market value, which include important developments in the Company’s operations, the prices at which the Company sold shares of its convertible preferred stock, the rights, preferences and privileges of the Company’s convertible preferred stock relative to those of the Company’s common stock, actual operating results, financial performance, external market conditions in the life sciences industry, general U.S. market conditions, equity market conditions of comparable public companies, and the lack of marketability of the Company’s common stock. For all grants subsequent to the IPO, the fair value of common stock was determined by using the closing price per share of common stock as reported on the Nasdaq Global Select Market. Expected Volatility The Company had no publicly available stock price information prior to its IPO and limited publicly available stock price information subsequent to its IPO and therefore the Company has used the historical volatility of the stock price of similar publicly traded peer companies. The historical volatility is calculated based on a period of time commensurate with the expected term assumptions. Expected Term For stock options granted to employees and directors, the expected term is calculated using the simplified method for “plain vanilla” stock option awards. The expected term for stock options granted to non-employees is the contractual term. Risk-Free Interest Rate The risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues similar in duration to the expected term of the equity-settled award. Expected Dividends The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay dividends on its common stock.
Net Loss Per Share Attributable to Common Shareholders	Net Loss Per Share Attributable to Common Stockholders Net loss per share of common stock is computed using the two-class method required for multiple classes of common stock and participating securities based upon their respective rights to receive dividends as if all income for the period has been distributed. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders is therefore the same for Class A and Class B common stock on an individual or combined basis. The Company’s participating securities include the Company’s convertible preferred stock, as the holders are entitled to receive noncumulative dividends on a pari passu basis in the event that a dividend is paid on common stock. The Company also considers any shares issued on the early exercise of stock options subject to repurchase to be participating securities because holders of such shares have non-forfeitable dividend rights in the event a dividend is paid on common stock. The holders of convertible preferred stock, as well as the holders of early exercised shares subject to repurchase, do not have a contractual obligation to share in losses. Basic net loss per share attributable to common stockholders 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, adjusted for outstanding shares that are subject to repurchase. Diluted net loss per share is computed by giving effect to all potentially dilutive securities outstanding for the period using the treasury stock method or the if-converted method based on the nature of such securities. For periods in which the Company reports net losses, diluted net loss per common share attributable to common stockholders is the same as basic net loss per common share attributable to common stockholders, because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which is intended to simplify the accounting for income taxes. This standard removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing standards to improve consistent application. The Company adopted this standard as of January 1, 2021, which did not have a material impact on its financial statements as of the adoption date. In January 2020, the FASB issued ASU No. 2020-01, Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815). This standard clarifies the interaction between accounting standards related to equity securities, equity method investments, and certain derivative instruments. The Company adopted this standard as of January 1, 2021, which did not have a material impact on its financial statements as of the adoption date. Recently Issued Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This standard clarifies the definition of a lease and requires a lessee to recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-to-use asset representing its right to use the underlying asset for the lease term. In November 2019, the FASB issued ASU No. 2019-10 which extends the effective date of ASU No. 2016-02 for non-public business entities, including smaller reporting companies, to fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022. While the Company has not yet quantified the impact, these adjustments will increase total assets and total liabilities relative to such amounts reported prior to adoption.
Fair Value Measurements	There were no financial liabilities measured at fair value. The Company classifies money market funds within Level 1 of the fair value hierarchy because they are valued using bank balances or quoted market prices. The Company classifies its investments in U.S. Treasury securities (Treasury bills, Treasury notes, and Treasury bonds) as Level 2 instruments and obtains fair value from an independent pricing service, which may use quoted market prices for identical or comparable instruments or model-driven valuations using observable market data or inputs corroborated by observable market data. The carrying amount of the Company’s other receivables, prepaid expenses, other current assets, accounts payable, and accrued expenses approximate fair value due to their short maturities.

- Definition

Disclosure of accounting policy for revenue from contract with customer.

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+ Details

Summary of Significant Accounting Policies and Basis of Presentation (Tables)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Schedule of Cash and Cash Equivalents


	March 31,		December 31,
	2021		2020

Cash and cash equivalents	$	445,763	$	333,585
Restricted cash	343		343
Total cash, cash equivalents and restricted cash	$	446,106	$	333,928

Fair Value Measurements and Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets Measured on Recurring Basis

The following tables set forth the fair value of the Company’s financial assets that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands).


		March 31, 2021
		Level 1		Level 2		Level 3		Total
Assets:	Classification:
Money market funds	Cash and cash equivalents	$	444,668	$	—	$	—	$	444,668
U.S. Treasury securities	Investments	—		85,379		—		85,379
Total assets measured at fair value		$	444,668	$	85,379	$	—	$	530,047


		December 31, 2020
		Level 1		Level 2		Level 3		Total
Assets:	Classification:
Money market funds	Cash and cash equivalents	$	333,585	$	—	$	—	$	333,585
U.S. Treasury securities	Investments	—		98,278		—		98,278
Total assets measured at fair value		$	333,585	$	98,278	$	—	$	431,863

Schedule of Debt Securities, Available-for-sale, Unrealized Gain

The following is a summary of the Company’s cash equivalents and investments and the gross unrealized holding gains and losses (in thousands):


	March 31, 2021
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses		Fair Value
Assets:
Money market funds	$	444,668	$	—	$	—	$	444,668
U.S. Treasury securities	85,351		28		—		85,379
Total	$	530,019	$	28	$	—	$	530,047


	December 31, 2020
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses		Fair Value
Assets:
Money market funds	$	333,585	$	—	$	—	$	333,585
U.S. Treasury securities	98,223		57		(2)		98,278
Total	$	431,808	$	57	$	(2)	$	431,863

Other Financial Statement Information (Tables)

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Schedule of Inventory

Inventory

Inventory consists of the following (in thousands):


	March 31,		December 31,
	2021		2020

Raw materials	$	622	$	—
Finished goods	919		551
Total inventory	$	1,541	$	551

Schedule of Other Receivables

Other receivables consist of the following (in thousands):


	March 31,		December 31,
	2021		2020

Interest receivable	$	335	$	120
Other	178		142
Total other receivables	$	513	$	262

Schedule of Property and Equipment

Property and equipment, net consists of the following (in thousands):


	March 31,		December 31,
	2021		2020

Laboratory equipment	$	8,774	$	8,075
Computer equipment and software	206		182
Furniture and fixtures	241		241
Leasehold improvements	2,294		2,294
Property and equipment	11,515		10,792
Less: accumulated depreciation and amortization	2,833		2,351
Total property and equipment, net	$	8,682	$	8,441

Schedule of Accrued Liabilities

Accrued expenses consist of the following (in thousands):


	March 31,		December 31,
	2021		2020

Accrued compensation	$	1,446	$	2,866
Accrued professional services	1,314		1,074
Restricted stock liability, current	483		484
Other	958		723
Total accrued expenses	$	4,201	$	5,147

Capital Stock and Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

Schedule of Stock by Class

Common stock issued and outstanding is as follows:


	March 31,	December 31,
	2021	2020

Class A common stock	56,606,968	53,395,319
Class B common stock	4,702,381	5,865,732
Total common stock issued and outstanding	61,309,349	59,261,051

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

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+ Details

Equity Incentive Plans (Tables)

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

Stock option activity for the three months ended March 31, 2021 is as follows:


	Options Outstanding	Weighted Average Exercise Price
Balance - December 31, 2020	9,551,105	$	5.55
Options granted	768,624	59.94
Options exercised	(399,174)	0.44
Options cancelled and forfeited	(81,201)	5.70
Balance - March 31, 2021	9,839,354	$	10.00
Vested and exercisable, March 31, 2021	1,616,370	$	2.44

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity

The activity of restricted shares of Class A common stock for the three months ended March 31, 2021 is as follows:


	Number of Shares	Weighted-Average Grant Date Fair Value
Unvested at December 31, 2020	775,641	$	1.77
Granted	10,728	1.66
Repurchased	(876)	1.55
Vested	(133,075)	2.07
Unvested at March 31, 2021	652,418	$	1.71

Share-based Payment Arrangement, Restricted Stock Unit, Activity

The Company has granted RSUs under the 2020 RSU Plan and the 2020 Plan. RSU activity for the three months ended March 31, 2021 is as follows:


	Restricted Stock Units	Weighted-Average Grant Date Fair Value
Balance at December 31, 2020	491,318	$	7.91
Granted	200,233	60.06
Vested	(1,120)	34.35
Cancelled	(947)	19.00
Balance at March 31, 2021	689,484	$	23.05

Share-based Payment Arrangement, Expensed and Capitalized, Amount

The following table summarizes the components of stock-based compensation recognized in the Company’s condensed consolidated statements of operations and comprehensive loss (in thousands):


	Three Months Ended March 31,
	2021		2020

Research and development	$	1,492	$	182
Selling, general and administrative	4,547		397
Total stock-based compensation	$	6,039	$	579

Commitments (Tables)

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases

As of March 31, 2021, future minimum commitments under the Company’s non-cancelable facility operating lease are as follows:


Years ending December 31,	(in thousands)
2021 (nine months remaining)	$	596
2022	1,279
2023	1,783
2024	1,833
2025	1,884
Thereafter	13,178
Total	$	20,553

Net Loss Per Share Attributable To Common Stockholders (Tables)

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

The following table shows the computation of basic and diluted net loss per share (in thousands, except share and per share data):


	Three Months Ended March 31,
	2021		2020

Numerator:
Net loss attributable to common stockholders	$	(16,429)	$	(5,493)
Denominator:
Weighted-average common shares used in computing net loss per share attributable to common stockholders, basic and diluted	59,887,842		8,944,284
Net loss per share attributable to common stockholders, basic and diluted	$	(0.27)	$	(0.61)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share


	March 31,
	2021	2020

Convertible preferred stock	—	22,173,216
Class A common stock options issued and outstanding	9,839,354	5,701,527
Restricted common stock subject to future vesting	652,418	2,836,759
Restricted stock units	689,484	—
Total	11,181,256	30,711,502

Organization, Consolidation and Presentation of Financial Statements (Details) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended
	Feb. 01, 2021 USD ($) $ / shares shares	Nov. 30, 2020	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Issuance of stock (in shares) \| shares	1,650,000
Public offering price (in usd per share) \| $ / shares	$ 67.00
Proceeds from issuance of common stock upon follow-on public offering, net of issuance costs	$ 103,000		$ 103,595	$ 0
Offering transaction costs	$ 7,600		7,591
Reverse stock split, conversion ratio		0.4673
Cash, cash equivalents, and investments			531,100
Accumulated deficit			$ (71,790)		$ (55,361)

Summary of Significant Accounting Policies and Basis of Presentation - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 445,763	$ 333,585
Restricted cash	343	343
Total cash, cash equivalents and restricted cash	$ 446,106	$ 333,928	$ 15,751	$ 17,828

Fair Value Measurements and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total assets measured at fair value	$ 530,047	$ 431,863
Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market funds	444,668	333,585
U.S. Treasury securities	85,379	98,278
Total assets measured at fair value	530,047
Level 1 \| Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market funds	444,668	333,585
U.S. Treasury securities	0	0
Total assets measured at fair value	444,668	333,585
Level 2 \| Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market funds	0	0
U.S. Treasury securities	85,379	98,278
Total assets measured at fair value	85,379	98,278
Level 3 \| Fair Value, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market funds	0	0
U.S. Treasury securities	0	0
Total assets measured at fair value	$ 0	$ 0

Fair Value Measurements and Fair Value of Financial Instruments - Unrealized Gain (Loss) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Amortized Cost Basis	$ 530,019	$ 431,808
Unrealized Gains	28	57
Unrealized Losses	0	(2)
Fair Value	530,047	431,863
Money market funds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Amortized Cost Basis	444,668	333,585
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	444,668	333,585
U.S. Treasury securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Amortized Cost Basis	85,351	98,223
Unrealized Gains	28	57
Unrealized Losses	0	(2)
Fair Value	$ 85,379	$ 98,278

Other Financial Statement Information - Schedule of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 622	$ 0
Finished goods	919	551
Total inventory	$ 1,541	$ 551

Other Financial Statement Information - Schedule of Other Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Interest receivable	$ 335	$ 120
Other	178	142
Total other receivables	$ 513	$ 262

Other Financial Statement Information - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment	$ 11,515		$ 10,792
Less: accumulated depreciation and amortization	2,833		2,351
Property and equipment, net	8,682		8,441
Depreciation expense	500	$ 300
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment	8,774		8,075
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment	206		182
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	241		241
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 2,294		$ 2,294

Other Financial Statement Information - Schedule of Accrued Compensation (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Accrued compensation	$ 1,446	$ 2,866
Accrued professional services	1,314	1,074
Restricted stock liability, current	483	484
Other	958	723
Total accrued expenses	$ 4,201	$ 5,147

Revenue and Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jun. 30, 2020	Aug. 31, 2019	Feb. 28, 2019
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 256		$ 250
Research and Development Activties \| Pharmaceutical Company
Deferred Revenue Arrangement [Line Items]
Deferred revenue	500
Revenue recognized	300
Research and Development Activties \| Biotechnology company
Deferred Revenue Arrangement [Line Items]
Deferred revenue						$ 400
Grant revenue \| NH Grant
Deferred Revenue Arrangement [Line Items]
Deferred revenue				$ 900	$ 1,100
Revenue recognized	$ 100	$ 200

Capital Stock and Stockholders' Equity (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) vote $ / shares shares	Mar. 31, 2020 USD ($)	Dec. 31, 2020 $ / shares shares
Class of Stock [Line Items]
Common stock, authorized (in shares)	105,000,000
Preferred stock, authorized (in shares)	5,000,000		5,000,000
Proceeds from return of profit \| $	$ 11,403	$ 0
Class A common stock
Class of Stock [Line Items]
Common stock, authorized (in shares)	94,000,000		94,000,000
Common stock, par value (usd per share) \| $ / shares	$ 0.00001		$ 0.00001
Voting rights (per share) \| vote	1
Class B common stock
Class of Stock [Line Items]
Common stock, authorized (in shares)	6,000,000		6,000,000
Common stock, par value (usd per share) \| $ / shares	$ 0.00001		$ 0.00001
Voting rights (per share) \| vote	10

Capital Stock and Stockholders' Equity - Schedule of Common Stock by Class (Details) - shares	Mar. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Total common stock issued (in shares)	61,309,349	59,261,051
Total common stock outstanding (in shares)	61,309,349	59,261,051
Class A common stock
Class of Stock [Line Items]
Total common stock issued (in shares)	56,606,968	53,395,319
Total common stock outstanding (in shares)	56,606,968	53,395,319
Class B common stock
Class of Stock [Line Items]
Total common stock issued (in shares)	4,702,381	5,865,732
Total common stock outstanding (in shares)	4,702,381	5,865,732

Equity Incentive Plans - Additional Information (Details)	Mar. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	6,153,968
Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	8,302,701
Class A common stock \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	1,195,327

Equity Incentive Plans - Activity of Stock Options for the Period (Details)	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Options Outstanding
Beginning balance (in shares) \| shares	9,551,105
Options granted (in shares) \| shares	768,624
Options exercised (in shares) \| shares	(399,174)
Options cancelled and forfeited (in shares) \| shares	(81,201)
Ending balance (in shares) \| shares	9,839,354
Vested and exercisable (in shares) \| shares	1,616,370
Weighted Average Exercise Price
Beginning balance (in shares) \| $ / shares	$ 5.55
Options granted (in usd per share) \| $ / shares	59.94
Options exercised (in usd per share) \| $ / shares	0.44
Options cancelled and forfeited (in usd per share) \| $ / shares	5.70
Ending balance (in shares) \| $ / shares	10.00
Vested and exercisable (in usd per share) \| $ / shares	$ 2.44

Equity Incentive Plans - Restricted Stock Option Activity (Details) - Restricted Stock Options	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Number of Shares
Beginning balance (in shares) \| shares	775,641
Granted (in shares) \| shares	10,728
Repurchased (in shares) \| shares	(876)
Vested (in shares) \| shares	(133,075)
Ending balance (in shares) \| shares	652,418
Weighted-Average Grant Date Fair Value
Beginning balance (in usd per share) \| $ / shares	$ 1.77
Granted (in usd per share) \| $ / shares	1.66
Repurchased (in usd per share) \| $ / shares	1.55
Vested (in usd per share) \| $ / shares	2.07
Ending balance (in usd per share) \| $ / shares	$ 1.71

Equity Incentive Plans - RSU Activity for the Period (Details) - Restricted stock units	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Restricted Stock Units
Beginning balance (in shares) \| shares	491,318
Granted (in shares) \| shares	200,233
Vested (in shares) \| shares	(1,120)
Cancelled (in shares) \| shares	(947)
Ending balance (in shares) \| shares	689,484
Weighted-Average Grant Date Fair Value
Beginning balance (in usd per share) \| $ / shares	$ 7.91
Granted (in usd per share) \| $ / shares	60.06
Vested (in usd per share) \| $ / shares	34.35
Cancelled (in usd per share) \| $ / shares	19.00
Ending balance (in usd per share) \| $ / shares	$ 23.05

Equity Incentive Plans - Stock Based Compensation Allocation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 6,039	$ 579
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	1,492	182
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 4,547	$ 397

Commitments - Facility Lease Agreement Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Other Commitments [Line Items]
Not yet commenced, renewal term	127 months 15 days
Annual base rent	$ 0.9
Abatement period	9 months
Lease payments, annual increase, final year total	$ 1.2
Tenant incentives	$ 2.4
Current renewal term	5 years
Rent expense		$ 0.2	$ 0.2
Facility Lease Agreement Letter of Credit \| Letter of Credit
Other Commitments [Line Items]
Letter of credit issued				$ 0.3

Commitment and Contingencies - Minimum Commitments (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2021 (nine months remaining)	$ 596
2022	1,279
2023	1,783
2024	1,833
2025	1,884
Thereafter	13,178
Total	$ 20,553

Commitments - Purchase Commitments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Purchase obligations outstanding	$ 4.6	$ 3.1

Prognomiq, Inc. (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Business Combinations [Abstract]
Other receivables, related parties	$ 0.1	$ 0.1

Net Loss Per Share Attributable To Common Stockholders - Computation of EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net loss attributable to common stockholders	$ (16,429)	$ (5,493)
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Weighted-average common shares used in computing net loss per share attributable to common stockholders, basic (in shares)	59,887,842	8,944,284
Weighted-average common shares used in computing net loss per share attributable to common stockholders, diluted (in shares)	59,887,842	8,944,284
Net loss per share available to common shareholders, basic (in usd per share)	$ (0.27)	$ (0.61)
Net loss per share available to common shareholders, diluted (in usd per share)	$ (0.27)	$ (0.61)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Net Loss Per Share Attributable To Common Stockholders - Potentially Dilutive Securities (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	11,181,256	30,711,502
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)	0	22,173,216
Class A common stock options issued and outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	9,839,354	5,701,527
Restricted common stock subject to future vesting
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	652,418	2,836,759
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	689,484	0

Subsequent Events (Details) - Subsequent Event	Apr. 30, 2021 USD ($) vote
Subsequent Event [Line Items]
Amount of square footage \| vote	25,000
Lease term	11 years
Monthly operating expense \| $	$ 160,000