Adaptive Biotechnologies (ADPT) 10-Q 5 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Trading Symbol	ADPT
Entity Registrant Name	ADAPTIVE BIOTECHNOLOGIES CORPORATION
Entity Central Index Key	0001478320
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Title of 12(b) Security	Common stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		140,311,141
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Interactive Data Current	Yes
Entity File Number	001-38957
Entity Tax Identification Number	27-0907024
Entity Address, Address Line One	1551 Eastlake Avenue East
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98102
City Area Code	(206)
Local Phone Number	659-0067
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	WA

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 173,624,000	$ 123,436,000
Short-term marketable securities (amortized cost of $540,016 and $564,036, respectively)	540,640,000	564,833,000
Accounts receivable, net	19,754,000	10,047,000
Inventory	17,422,000	14,063,000
Prepaid expenses and other current assets	13,520,000	14,535,000
Total current assets	764,960,000	726,914,000
Long-term assets
Property and equipment, net	56,308,000	39,692,000
Operating lease right-of-use assets	88,504,000	99,350,000
Long-term marketable securities (amortized cost of $30,681 and $118,429, respectively)	30,688,000	118,525,000
Restricted cash	2,138,000	2,138,000
Intangible assets, net	9,806,000	10,225,000
Goodwill	118,972,000	118,972,000
Other assets	717,000	598,000
Total assets	1,072,093,000	1,116,414,000
Current liabilities
Accounts payable	5,197,000	3,237,000
Accrued liabilities	13,484,000	13,162,000
Accrued compensation and benefits	5,431,000	11,950,000
Current portion of operating lease liabilities	4,308,000	3,529,000
Current portion of deferred revenue	78,348,000	73,319,000
Total current liabilities	106,768,000	105,197,000
Long-term liabilities
Operating lease liabilities, less current portion	95,252,000	104,333,000
Deferred revenue, less current portion	144,356,000	163,618,000
Total liabilities	346,376,000	373,148,000
Commitments and contingencies (Note 9)
Shareholders’ equity
Preferred stock: $0.0001 par value, 10,000,000 shares authorized at March 31, 2021 and December 31, 2020; no shares issued and outstanding at March 31, 2021 and December 31, 2020
Common stock: $0.0001 par value, 340,000,000 shares authorized at March 31, 2021 and December 31, 2020; 139,884,698 and 137,646,896 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	14,000	14,000
Additional paid-in capital	1,277,197,000	1,253,971,000
Accumulated other comprehensive gain	631,000	893,000
Accumulated deficit	(552,254,000)	(511,612,000)
Total Adaptive Biotechnologies Corporation shareholders’ equity	725,588,000	743,266,000
Noncontrolling interest	129,000
Total shareholders’ equity	725,717,000	743,266,000
Total liabilities and shareholders’ equity	$ 1,072,093,000	$ 1,116,414,000

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Amortized cost of short-term marketable securities	$ 540,016	$ 564,036
Amortized cost of long-term marketable securities	$ 30,681	$ 118,429
Preferred stock par value	$ 0.0001	$ 0.0001
Preferred stock authorized	10,000,000	10,000,000
Preferred stock issued	0	0
Preferred stock outstanding	0	0
Common stock par value	$ 0.0001	$ 0.0001
Common stock authorized	340,000,000	340,000,000
Common stock issued	139,884,698	137,646,896
Common stock outstanding	139,884,698	137,646,896

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue
Total revenue	$ 38,442	$ 20,910
Operating expenses
Cost of revenue	9,991	5,343
Research and development	33,772	23,935
Sales and marketing	20,604	14,007
General and administrative	14,936	11,821
Amortization of intangible assets	419	424
Total operating expenses	79,722	55,530
Loss from operations	(41,280)	(34,620)
Interest and other income, net	638	2,894
Income tax benefit		323
Net loss	$ (40,642)	$ (31,403)
Net loss per share attributable to common shareholders, basic and diluted	$ (0.29)	$ (0.25)
Weighted-average shares used in computing net loss per share attributable to common shareholders, basic and diluted	138,967,754	126,058,389
Sequencing Revenue
Revenue
Total revenue	$ 15,174	$ 9,469
Development Revenue
Revenue
Total revenue	$ 23,268	$ 11,441

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Financial Position [Abstract]
Net loss	$ (40,642)	$ (31,403)
Change in unrealized gains and losses on investments	(262)	2,642
Comprehensive loss	$ (40,904)	$ (28,761)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Revision of Prior Period, Accounting Standards Update, Adjustment	Common Stock	Additional Paid In Capital	Accumulated Other Comprehensive Gain	Noncontrolling Interest	Accumulated Deficit	Accumulated DeficitRevision of Prior Period, Accounting Standards Update, Adjustment
Beginning Balance at Dec. 31, 2019	$ 571,039	$ 93	$ 12	$ 935,834	$ 671		$ (365,478)	$ 93
Beginning Balance, Shares at Dec. 31, 2019			125,238,142
Accounting Standards Update Extensible List	us-gaap:AccountingStandardsUpdate201602Member
Issuance of common stock for cash upon exercise of stock options	$ 4,517			4,517
Issuance of common stock for cash upon exercise of stock options, Shares			1,381,437
Vesting of restricted stock units			2,250
Common stock option and restricted stock unit share-based compensation	4,675			4,675
Other comprehensive income (loss)	2,642				2,642
Net loss	(31,403)						(31,403)
Ending Balance at Mar. 31, 2020	551,563		$ 12	945,026	3,313		(396,788)
Ending Balance, Shares at Mar. 31, 2020			126,621,829
Beginning Balance at Dec. 31, 2020	743,266		$ 14	1,253,971	893		(511,612)
Beginning Balance, Shares at Dec. 31, 2020			137,646,896
Issuance of common stock upon exercise of common stock warrants, Shares			54,162
Issuance of common stock for cash upon exercise of stock options	$ 14,442			14,442
Issuance of common stock for cash upon exercise of stock options, Shares	2,183,640		2,183,640
Common stock option and restricted stock unit share-based compensation	$ 8,484			8,484
Capital contributions for Spin Technologies, Inc.	429			300		$ 129
Other comprehensive income (loss)	(262)				(262)
Net loss	(40,642)						(40,642)
Ending Balance at Mar. 31, 2021	$ 725,717		$ 14	$ 1,277,197	$ 631	$ 129	$ (552,254)
Ending Balance, Shares at Mar. 31, 2021			139,884,698

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net loss	$ (40,642)	$ (31,403)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	2,252	1,554
Noncash lease expense	1,732	631
Share-based compensation expense	8,484	4,675
Intangible assets amortization	419	424
Investment amortization	2,108	(556)
Benefit from income tax		(323)
Other	(9)	114
Changes in operating assets and liabilities:
Accounts receivable, net	(9,707)	3,278
Inventory	(3,359)	(1,449)
Prepaid expenses and other current assets	1,273	3,526
Accounts payable and accrued liabilities	(7,257)	(4,603)
Operating lease liabilities	813	(333)
Deferred revenue	(14,233)	(6,926)
Other	(119)	(215)
Net cash used in operating activities	(58,245)	(31,606)
Investing activities
Purchases of property and equipment	(15,841)	(2,963)
Purchases of marketable securities	(15,340)	(107,747)
Proceeds from sales and maturities of marketable securities	125,000	253,469
Net cash provided by investing activities	93,819	142,759
Financing activities
Proceeds from exercise of stock options	14,185	4,959
Proceeds from initial capital contributions for Spin Technologies, Inc.	429
Net cash provided by financing activities	14,614	4,959
Net increase in cash, cash equivalents and restricted cash	50,188	116,112
Cash, cash equivalents and restricted cash at beginning of year	125,574	98,714
Cash, cash equivalents and restricted cash at end of period	175,762	214,826
Noncash investing and financing activities
Purchases of equipment included in accounts payable and accrued liabilities	$ 7,698	627
Derecognition of lease financing arrangements upon adoption of guidance on accounting for leases		$ 36,607

Organization and Description of

Organization and Description of Business	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Description of Business	1. Organization Adaptive Biotechnologies Corporation (“we,” “us” or “our”) is a commercial-stage company advancing the field of immune medicine by harnessing the inherent biology of the adaptive immune system to transform the diagnosis and treatment of disease. We believe the adaptive immune system is nature’s most finely tuned diagnostic and therapeutic for most diseases, but the inability to decode it has prevented the medical community from fully leveraging its capabilities. Our immune medicine platform applies our proprietary technologies to read the diverse genetic code of a patient’s immune system and aims to understand precisely how the immune system detects and treats disease in that patient. We capture these insights in our dynamic clinical immunomics database, which is underpinned by computational biology and machine learning, and use them to develop and commercialize clinical products and services that we are tailoring to each individual patient. We have commercial products and services and a robust pipeline of clinical products and services that we are designing to diagnose, monitor and enable the treatment of diseases, such as cancer, autoimmune conditions and infectious diseases. We were incorporated in the State of Washington on September 8, 2009 under the name Adaptive TCR Corporation. On December 21, 2011, we changed our name to Adaptive Biotechnologies Corporation. We are headquartered in Seattle, Washington. New Sequencing Technology In 2021, we formed a corporate subsidiary, Spin Technologies, Inc. (“SpinTech”), in order to facilitate the development of a potential new early-stage sequencing technology that is ancillary to our core business. We have a 70% ownership interest in SpinTech. All intercompany transactions and balances between us and this majority-owned subsidiary have been eliminated in consolidation. The remaining interest, held by certain of our related parties and related family trusts, was reported as noncontrolling interest in our unaudited condensed consolidated financial statements.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies	2. Significant Basis The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures at the date of the financial statements, as well as the reported amounts of revenues and expenses during the periods presented. We base our estimates on historical experience and other relevant assumptions that we believe to be reasonable under the circumstances. Estimates are used in several areas including, but not limited to, estimates of progress to date for certain performance obligations and the transaction price for certain contracts with customers, share-based compensation, the provision for income taxes, including related reserves, and goodwill, among others. These estimates generally involve complex issues and require judgments, involve the analysis of historical results and prediction of future trends, can require extended periods of time to resolve and are subject to change from period to period. Actual results may differ materially from management’s estimates. Unaudited Interim Condensed Consolidated Financial Statements In our opinion, the accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. These unaudited condensed consolidated financial statements include all adjustments necessary to fairly state the financial position and the results of our operations and cash flows for interim periods in accordance with GAAP. All such adjustments are of a normal, recurring nature. Interim-period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited financial statements and notes included in our Annual Report on Form 10-K for the year ended December 31, 2020 filed with the SEC on February 24, 2021. Restricted Cash We are required to maintain certain balances under lease arrangements for some of our property and facility leases. We had restricted cash of $2.1 million as of March 31, 2021 and December 31, 2020. Leases We determine if an arrangement contains a lease at inception. We have operating lease agreements for the laboratory and office facilities that we occupy, as well as server space. Operating lease right-of-use (“ROU”) assets and operating lease liabilities are recognized at the date the underlying asset becomes available for our use and are based on the present value of the future minimum lease payments over the lease term. ROU assets also include any initial direct costs incurred and any lease payments made at or before the lease commencement date, less lease incentives received. As our leases generally do not provide an implicit interest rate, the present value of our future minimum lease payments is determined using our incremental borrowing rate. This rate is an estimate of the collateralized borrowing rate we would incur on our future lease payments over a similar term and is based on the information available to us at the lease commencement date, or as of January 1, 2020 for commenced leases that existed as of our adoption of the new lease standard. Certain of our leases contain options to extend or terminate the lease; lease terms are adjusted for these options only when it is reasonably certain we will exercise these options. Our lease agreements do not contain residual value guarantees or covenants. We have made a policy election regarding our real estate leases not to separate nonlease components from lease components, to the extent they are fixed. Nonlease components that are not fixed are expensed as incurred as variable lease expense. Our leases for laboratory and office facilities typically include variable nonlease components, such as common-area maintenance costs. We have also elected not to record on the balance sheet a lease that has a lease term of twelve months or less and does not contain a purchase option that we are reasonably certain to exercise. Lease expense is recognized on a straight-line basis over the terms of the leases. Incentives granted under our facilities leases, including rent holidays, are recognized as adjustments to lease expense on a straight-line basis over the terms of the leases. Concentrations We are subject to a concentration of risk from a limited number of suppliers, or in some cases single suppliers, for some of our laboratory instruments and materials. This risk is managed by targeting a quantity of surplus stock. Cash, cash equivalents and marketable securities are financial instruments that potentially subject us to concentrations of credit risk. We invest in money market funds, United States (“U.S.”) government debt securities, U.S. government agency securities, commercial paper and corporate bonds with high-quality accredited financial institutions. Significant customers are those that represent more than 10% of our total revenue or accounts receivable, net balances for the periods and as of each balance sheet date presented, respectively. Revenue from these customers reflects their purchase of our products and services and our collaboration efforts with Genentech. For each significant customer, revenue as a percentage of total revenue for the periods presented and accounts receivable, net as a percentage of total accounts receivable, net as of the dates presented were as follows: Revenue Accounts Receivable, Net Three Months Ended March 31, March 31, December 31, 2021 2020 2021 2020 Customer A *% *% *% 19.1 % Customer B 10.4 * 17.8 12.2 Customer D 10.0 * 19.4 * Customer E * * 17.8 * Genentech, Inc. and Roche Group 42.1 54.4 * * * less than 10% Revenue We recognize revenue in accordance with Accounting Standards Codification (“ASC”) Topic 606 (“ASC 606”), Revenue from Contracts with Customers Overview Our revenue is generated from immunosequencing (“sequencing”) products and services (“sequencing revenue”) and from regulatory or development support services leveraging our immune medicine platform (“development revenue”). When revenue generating contracts have elements of both sequencing revenue and development revenue, we classify revenue based on the nature of the performance obligation and the allocated transaction price. Sequencing Revenue Sequencing revenue reflects the amounts generated from providing sequencing services and testing through our clonoSEQ and immunoSEQ products and services to our clinical and research customers, respectively. For clinical customers, we derive revenues from providing our clonoSEQ report to ordering physicians, and we bill and receive payments from medical institutions and commercial and government third-party payors. In these transactions, we have identified one performance obligation: the delivery of a clonoSEQ report. As payment from the respective payors may vary based on the various reimbursement rates and patient responsibilities, we consider the transaction price to be variable and record an estimate of the transaction price, subject to the constraint for variable consideration, as revenue at the time of delivery. The estimate of transaction price is based on historical and expected reimbursement rates with the various payors, which are monitored in subsequent periods and adjusted as necessary based on actual collection experience. For our clonoSEQ coverage under Medicare, we bill an episode of treatment when we deliver the first eligible test results. This billing contemplates all necessary tests required during a patient’s treatment cycle, which is currently estimated at approximately four tests per patient, including the initial sequence identification test. Revenue recognition commences at the time the initial billable test result is delivered and is based upon cumulative tests delivered to date. We estimate the number of tests we expect to deliver over a patient’s treatment cycle based on historical testing frequencies for patients by indication. These estimates are subject to change as we develop more information about utilization over time. Any unrecognized revenue from the initial billable test is recorded as deferred revenue and is recognized as we deliver the remaining tests in a patient’s treatment cycle or when it becomes remote that a patient will receive additional testing and we have not delivered our estimate of total tests. For research customers, contracts typically include an amount billed in advance of services (“upfront”) and subsequent billings as sample results are delivered to the customer. Upfront amounts received are recorded as deferred revenue, which we recognize as revenue upon satisfaction of performance obligations. We have identified two typical performance obligations under the terms of our research service contracts: sequencing services and related data analysis. We recognize revenue for both identified performance obligations as sample results are delivered to the customer. Development We derive revenue by providing services through development agreements to biopharmaceutical customers who seek access to our immune medicine platform technologies. We generate revenues from the delivery of professional support activities pertaining to the use of immunoSEQ and our minimal residual disease (“MRD”) product in the development of the respective customers’ initiatives. The transaction price for these contracts may consist of a combination of non-refundable upfront fees, separately priced sequencing fees, progress-based milestones and regulatory milestones. The development agreements may include single or multiple performance obligations, depending on the contract. For certain contracts, we may perform services to support the biopharmaceutical customers’ regulatory submissions as part of their registrational trials. These services include regulatory support pertaining to our technology intended to be utilized as part of the submission, development of analytical plans for our sequencing data, participation on joint research committees and assistance in completing a regulatory submission. Generally, these services are not distinct within the context of the contract and they are accounted for as a single performance obligation. When sequencing services are separately priced customer options, we assess if a material right exists and, if not, the customer option to purchase additional sequencing services is not considered part of the contract. Except for any non-refundable upfront fees, the other forms of compensation represent variable consideration. Variable consideration related to progress - based and regulatory milestones is estimated using the most likely amount method , where variable consideration is constrained until it is probable that a significant reversal of cumulative revenue recognized will not occur. Progress milestones , such as the first sample result delivered or final patient enrollment in a customer trial , are customer dependent and are included in the transaction price when the respective milestone is probable of occurring. Milestone payments that are not within our customers’ control, such as regulatory approvals, are not consider ed probable of being achieved until those approvals are received. Determining whether regulatory milestone payments are probable is an area that requires significant judgment. In making this assessment, we evaluate scientific, clinical, regulatory and other risks, as well as the level of effort and investment required to achieve the respective milestone. The primary method used to estimate standalone selling price for performance obligations is the adjusted market assessment approach. Using this approach, we evaluate the market in which we sell our services and estimate the price that a customer in that market would be willing to pay for our services. We recognize revenue using either an input or output measure of progress that faithfully depicts performance on a contract, depending on the contract. The measure used is dependent on the nature of the service to be provided in each contract. Selecting the measure of progress and estimating progress to date requires significant judgment. Net Loss Per Share Attributable to Common Shareholders We calculate basic net loss per share attributable to common shareholders by dividing the net loss attributable to common shareholders by the weighted-average number of shares of common stock outstanding for the period. The diluted net loss per share attributable to common shareholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period determined using the treasury stock method. For purposes of this calculation, common stock warrants, stock options and nonvested restricted stock units are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common shareholders, as their effect is anti-dilutive.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2021
Revenue From Contract With Customer [Abstract]
Revenue	3. Revenue MRD Development We have entered into agreements with biopharmaceutical customers to further develop and commercialize our MRD product and the biopharmaceutical customers’ therapeutics. Under each of the agreements, we received or will receive non-refundable upfront payments and could receive substantial additional payments upon reaching certain progress milestones or achieving certain regulatory milestones pertaining to the customers’ therapeutics and our MRD product. Under the contracts, we identify performance obligations, which may include: (1) obligations to provide services supporting the customer’s regulatory submission activities as they relate to our MRD product; and (2) sequencing services related to customer-provided samples for their regulatory submissions. The transaction price allocated to the respective performance obligations is estimated using an adjusted market assessment approach for the regulatory support services and a standalone selling price for the estimated immunosequencing services. At contract inception, we fully constrain any consideration related to the regulatory milestones, as the achievement of such milestones is subject to third-party regulatory approval and the customers’ own submission decision-making. We recognize revenue relating to the sequencing services as sequencing revenue over time using an output method based on the proportion of sample results delivered relative to the total amount of sample results expected to be delivered and when expected to be a faithful depiction of progress. We use the same method to recognize the regulatory support services. When an output method based on the proportion of sample results delivered is not expected to be a faithful depiction of progress, we utilize an input method based on estimates of effort completed using a cost-based model. We earned $7.0 million during the three months ended March 31, 2021 upon the achievement of certain regulatory milestones by our respective customers’ therapeutics, all of which was recognized as revenue within the respective period, as we determined the amounts were consistent with our estimated standalone selling prices and the respective performance obligations were complete. We recognized $7.2 million and $0.4 million in development revenue related to these contracts, inclusive of the aforementioned milestones, during the three months ended March 31, 2021 and 2020, respectively. As of March 31, 2021, in future periods we could receive up to an additional $306.5 million in milestone payments if certain regulatory approvals are obtained by our customers’ therapeutics in connection with MRD data generated from our MRD product. Genentech In December 2018, we entered into a worldwide collaboration and license agreement with Genentech (“Genentech Agreement”) to leverage our capability to develop cellular therapies in oncology. Subsequent to receipt of regulatory approval in January 2019, we received a non-refundable, upfront payment of $300.0 million in February 2019 and may be eligible to receive more than $1.8 billion over time, including payments of up to $75.0 million upon the achievement of specified regulatory milestones, up to $300.0 million upon the achievement of specified development milestones and up to $1,430.0 million upon the achievement of specified commercial milestones. In addition, we are separately able to receive tiered royalties at a rate ranging from the mid-single digits to the mid-teens on aggregate worldwide net sales of products arising from the strategic collaboration, subject to certain reductions, with aggregate minimum floors. Under the agreement, we are pursuing two product development pathways for novel T cell immunotherapies in which Genentech intends to use T cell receptors (“TCRs”) screened by our immune medicine platform to engineer and manufacture cellular medicines: • Shared Products. The shared products will use “off-the-shelf” TCRs identified against cancer antigens shared among patients (“Shared Products”). • Personalized Product. The personalized product will use patient-specific TCRs identified by real-time screening of TCRs against cancer antigens in each patient (“Personalized Product”). Under the terms of the agreement, we granted Genentech exclusive worldwide licenses to develop and commercialize TCR-based cellular therapies in the field of oncology, including licenses to existing shared antigen data packages. Additionally, Genentech has the right to determine which product candidates to further develop for commercialization purposes. We determined that this arrangement meets the criteria set forth in ASC Topic 808, Collaborative Arrangements In applying ASC 606, we identified the following performance obligations at the inception of the agreement: 1. License to utilize on an exclusive basis all TCR-specific platform intellectual property to develop and commercialize any licensed products in the field of oncology. 2. License to utilize all data and information within each shared antigen data package and any other know-how disclosed by us to Genentech in oncology. 3. License to utilize all private antigen TCR product data in connection with research and development activities in the field of use. 4. License to existing shared antigen data packages. 5. Research and development services for shared product development, including expansion of shared antigen data packages. 6. Research and development services for private product development. 7. Obligations to participate on various joint research, development and project committees. We determined that none of the licenses, research and development services or obligations to participate on various committees were distinct within the context of the contract, given such rights and activities were highly interrelated and there was substantial additional research and development to further develop the licenses. We considered factors such as the stage of development of the respective existing antigen data packages, the subsequent development that would be required to both identify and submit a potential target for investigational new drug acceptance under both product pathways and the variability in research and development pathways given Genentech’s control of product commercialization. Specifically, under the agreement, Genentech is not required to pursue development or commercialization activities pertaining to both product pathways and may choose to proceed with one or the other, as opposed to both. Accordingly, we determined that all of the identified performance obligations were attributable to one general performance obligation, which is to further the development of our TCR-specific platform, including data packages, and continue to make our TCR identification process available to Genentech to pursue either product pathway. Separately, we have a responsibility to Genentech to enter into a supply and manufacturing agreement for patient-specific TCRs as it pertains to any Personalized Product therapeutic. We determined this was an option right of Genentech should they pursue commercialization of a Personalized Product therapy. Because of the uncertainty resulting from the early stage of development, the novel approach of our collaboration with Genentech and our rights to future commercial milestones and royalty payments, we determined that this option right was not a material right that should be accounted for at inception. As such, we will account for the supply and manufacturing agreement when entered into between the parties. We determined the initial transaction price shall be made up of only the $300.0 million upfront, non-refundable payment, as all potential regulatory and development milestone payments were probable of significant revenue reversal given their achievement was highly dependent on factors outside our control. As a result, these payments were fully constrained and were not included in the transaction price as of March 31, 2021. We excluded the commercial milestones and potential royalties from the transaction price, as those items relate predominantly to the license rights granted to Genentech and will be assessed when and if such events occur. As there are potential substantive developments necessary, which Genentech may be able to direct, we determined that we would apply a proportional performance model to recognize revenue for our performance obligation. We measure proportional performance using an input method based on costs incurred relative to the total estimated costs of research and development efforts to pursue both the Shared Product and Personalized Product pathways. When any of the potential regulatory and development milestones are no longer fully constrained and included in the transaction price, such amounts will be recognized using the cumulative catch-up method based on proportional performance at such time. We currently expect to recognize the revenue over a period of approximately seven to eight years from the effective date. This estimate of the research and development period considers pursuit options of development activities supporting both the Shared Product and the Personalized Product, but may be reduced or increased based on the various activities as directed by the joint committees, decisions made by Genentech, regulatory feedback or other factors not currently known. We recognized revenue of $15.6 million and $10.9 million during the three months ended March 31, 2021 and 2020, respectively, related to the Genentech Agreement. Costs related to the Genentech Agreement are included in research and development expenses.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value The following tables set forth the fair value of financial assets as of March 31, 2021 and December 31, 2020 that were measured at fair value on a recurring basis (in thousands): March 31, 2021 Level 1 Level 2 Level 3 Total Financial assets Money market funds $ 151,330 $ — $ — $ 151,330 U.S. government debt securities — 559,788 — 559,788 Corporate bonds — 11,540 — 11,540 Total financial assets $ 151,330 $ 571,328 $ — $ 722,658 December 31, 2020 Level 1 Level 2 Level 3 Total Financial assets Money market funds $ 103,283 $ — $ — $ 103,283 U.S. government debt securities — 671,777 — 671,777 Corporate bonds — 11,581 — 11,581 Total financial assets $ 103,283 $ 683,358 $ — $ 786,641 Level 1 securities include highly liquid money market funds, for which we measure the fair value based on quoted prices in active markets for identical assets or liabilities. Level 2 securities consist of U.S. government debt securities and corporate bonds, and are valued based on recent trades of securities in inactive markets or on quoted market prices of similar instruments and other significant inputs derived from or corroborated by observable market data.

Investments

Investments	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Investments	5. Investments Available-for-sale investments consisted of the following as of March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Short-term marketable securities U.S. government debt securities $ 528,522 $ 578 $ — $ 529,100 Corporate bonds 11,494 46 — 11,540 Total short-term marketable securities $ 540,016 $ 624 $ — $ 540,640 Long-term marketable securities U.S. government debt securities $ 30,681 $ 10 $ (3 ) $ 30,688 Total long-term marketable securities $ 30,681 $ 10 $ (3 ) $ 30,688 December 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Short-term marketable securities U.S. government debt securities $ 552,539 $ 723 $ (10 ) $ 553,252 Corporate bonds 11,497 86 (2 ) 11,581 Total short-term marketable securities $ 564,036 $ 809 $ (12 ) $ 564,833 Long-term marketable securities U.S. government debt securities $ 118,429 $ 98 $ (2 ) $ 118,525 Total long-term marketable securities $ 118,429 $ 98 $ (2 ) $ 118,525 All the U.S. government debt securities and corporate bonds designated as short-term marketable securities have an effective maturity date that is equal to or less than one year from the respective balance sheet date. Those that are designated as long-term marketable securities have an effective maturity date that is more than one year from the respective balance sheet date. Accrued interest receivables are excluded from the amortized cost and estimated fair value of our marketable securities. Accrued interest receivables of $2.8 million and $2.5 million were presented separately within the prepaid expenses and other current assets line item on our unaudited condensed consolidated balance sheet as of March 31, 2021 and on our condensed consolidated balance sheet as of December 31, 2020, respectively. The following table presents the gross unrealized holding losses and fair value for investments in an unrealized loss position, and the length of time that individual securities have been in a continuous loss position, as of March 31, 2021 (in thousands): Less Than 12 Months 12 Months Or Greater Fair Value Unrealized Loss Fair Value Unrealized Loss U.S. government debt securities $ 10,240 $ (3 ) $ — $ — Corporate bonds 1,503 — — — Total available-for-sale securities $ 11,743 $ (3 ) $ — $ — We periodically review our available-for-sale securities to assess for credit impairment. Some of the factors considered in assessing impairment include the extent to which the fair value is less than the amortized cost basis, adverse conditions related to the security, an industry or geographic area, changes to security ratings or sector credit ratings and other relevant market data. As of March 31, 2021, we did not intend, nor were we more likely than not to be required, to sell our available-for-sale investments before the recovery of their amortized cost basis, which may be maturity. Based on our assessment, we concluded all impairment as of March 31, 2021 to be due to factors other than credit loss, such as changes in interest rates. A credit allowance was not recognized and the impairment of our available-for-sale securities was recorded in other comprehensive loss.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	6 . Goodwill There have been no changes in the carrying amount of goodwill since its recognition in 2015. Intangible assets subject to amortization as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands): March 31, 2021 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 20,000 $ (10,382 ) $ 9,618 Purchased intellectual property 325 (137 ) 188 Balance at March 31, 2021 $ 20,325 $ (10,519 ) $ 9,806 December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 20,000 $ (9,972 ) $ 10,028 Purchased intellectual property 325 (128 ) 197 Balance at December 31, 2020 $ 20,325 $ (10,100 ) $ 10,225 The developed technology was acquired in connection with our acquisition of Sequenta, Inc. in 2015. The remaining balance of the acquired technology and the purchased intellectual property is expected to be amortized over the next 5.8 years. As of March 31, 2021, expected future amortization expense for intangible assets was as follows (in thousands): 2021 (excluding the three months ended March 31, 2021) $ 1,280 2022 1,699 2023 1,699 2024 1,703 2025 1,699 Thereafter 1,726 Total future amortization expense $ 9,806

Deferred Revenue

Deferred Revenue	3 Months Ended
	Mar. 31, 2021
Revenue From Contract With Customer [Abstract]
Deferred Revenue	7 . Deferred Revenue Deferred revenue by revenue classification as of March 31, 2021 and December 31, 2020 was as follows (in thousands): March 31, 2021 December 31, 2020 Current deferred revenue Sequencing $ 17,191 $ 15,463 Development 61,157 57,856 Total current deferred revenue 78,348 73,319 Non-current deferred revenue Sequencing 662 724 Development 143,694 162,894 Total non-current deferred revenue 144,356 163,618 Total current and non-current deferred revenue $ 222,704 $ 236,937 Deferred revenue from our Genentech Agreement represents $58.6 million and $137.9 million of the current and non-current development deferred revenue balances, respectively, as of March 31, 2021 and $55.1 million and $157.0 million of the current and non-current development deferred revenue balances, respectively, as of December 31, 2020. In general, we expect that the current amounts will be recognized as revenue within 12 months and the non-current amounts will be recognized as revenue over a period of approximately five to six years from March 31, 2021. This period of time represents an estimate of the research and development period to develop cellular therapies in oncology, which may be reduced or increased based on the various development activities. Changes in deferred revenue during the three months ended March 31, 2021 were as follows (in thousands): Deferred revenue balance at December 31, 2020 $ 236,937 Additions to deferred revenue during the period 7,118 Revenue recognized during the period (21,351 ) Deferred revenue balance at March 31, 2021 $ 222,704 As of March 31, 2021, $19.0 million was recognized as revenue that was included in the deferred revenue balance at December 31, 2020. This is inclusive of $0.2 million of sequencing revenue recognized as a result of cancelled biopharmaceutical and research customer sequencing contracts, $0.2 million of sequencing revenue related to Medicare that was recognized due to our determination that additional testing for specific patients was remote and $0.4 million related to a change in anticipated samples to be received in connection with an MRD agreement.

Leases

Leases	3 Months Ended
	Mar. 31, 2021
Lessee Disclosure [Abstract]
Leases	8. Leases We have operating lease agreements for laboratory and office facilities in Seattle, Washington, South San Francisco, California and New York City, New York, as well as server space. We previously entered into a $2.1 million letter of credit with one of our financial institutions in connection with one of our leases. As of , we were not party to any finance leases. Our leases have remaining terms of 1.1 years to 12.4 years and include options to extend certain of the leases up to 10.0 years and terminate certain of the leases after 3.0 years. We adjust lease terms for these options only when it is reasonably certain we will exercise these options. As of , it was reasonably certain that we would exercise our option to terminate of our leases after 3.0 years. Other information related to our operating leases as of was as follows: Weighted-average remaining lease term (in years) 11.07 Weighted-average discount rate 4.6 % The following table reconciles our undiscounted operating lease cash flows to our operating lease liabilities as of (in thousands): 2021 (excluding the three months ended March 31, 2021) $ 6,120 2022 13,554 2023 13,318 2024 13,030 2025 13,419 Thereafter 89,236 Total undiscounted lease payments 148,677 Less: Imputed interest rate (34,873 ) Tenant improvement receivables (14,244 ) Total operating lease liabilities $ 99,560 Less: current portion (4,308 ) Operating lease liabilities, less current portion $ 95,252 Operating lease expense was $3.1 million and $1.1 million for the three months ended , respectively. Variable lease expense for operating leases was $0.7 million and $0.5 million for the three months ended , respectively. Cash paid for amounts included in the measurement of lease liabilities was $0.5 million, net of $1.2 million of cash received for tenant improvement allowances during the three months ended March 31, 2021. Cash paid for amounts included in the measurement of lease liabilities was $0.8 million, net of $0.3 million of cash received for tenant improvement allowances during the three months ended March 31, 2020 Lease Not Yet Commenced In March 2021, we entered into a lease to rent approximately 27,000 square feet of a warehouse in Bothell, Washington. Rent obligations commence six months after lease commencement and the lease expires 120 months thereafter, subject to an early termination option after the seventh year and an option to twice extend the lease for five years. This lease will be assessed for classification and a lease liability and corresponding ROU asset will be recorded upon lease commencement. Future non-cancellable undiscounted lease payments, exclusive of operating and maintenance costs, total million. Furthermore, in connection with this lease, the landlord agreed to fund $1.2 million in improvements.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	9 . Commitments and Contingencies Legal Proceedings We are subject to claims and assessments from time to time in the ordinary course of business. We will accrue a liability for such matters when it is probable that a liability has been incurred and the amount can be reasonably estimated. When only a range of possible loss can be established, the most probable amount in the range is accrued. If no amount within this range is a better estimate than any other amount within the range, the minimum amount in the range is accrued. We are not party to any material legal proceedings as of March 31, 2021. Indemnification Agreements In the ordinary course of business, we may provide indemnification of varying scope and terms to vendors, lessors, customers and other parties with respect to certain matters including, but not limited to, losses arising out of breach of our agreements with them or from intellectual property infringement claims made by third parties. In addition, we have entered into indemnification agreements with members of our board of directors and certain of our executive officers that will require us to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments that we could be required to make under these indemnification agreements is, in many cases, unlimited. We have not incurred any material costs as a result of such indemnifications and are not currently aware of any indemnification claims.

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Shareholders' Equity	10 . Shareholders’ Preferred Stock We are authorized to issue 10,000,000 shares of preferred stock, par value $0.0001 per share. As of March 31, 2021, no shares of preferred stock were outstanding. Common Stock We are authorized to issue 340,000,000 shares of common stock. Our common stock has a par value of $0.0001 per share, no preferences or privileges and is not redeemable. Holders of our common stock are entitled to one vote for each share of common stock held. The holders of record of outstanding shares of common stock shall be entitled to receive, when, as and if declared, out of funds legally available, such cash and other dividends as may be declared from time to time. As of March 31, 2021, we had 139,884,698 shares of common stock outstanding. As of March 31, 2021, we have reserved shares of common stock for the following: Shares issuable upon the exercise of outstanding common stock options and the vesting of outstanding common restricted stock units granted 14,198,533 Shares available for future grant under the 2019 Equity Incentive Plan 23,600,732 Shares available for future grant under the Employee Stock Purchase Plan 2,804,298 Total shares of common stock reserved for future issuance 40,603,563 Our 2019 Equity Incentive Plan (“2019 Plan”) provides for annual increases in the number of shares that may be issued under the 2019 Plan on January 1, 2020 and on each subsequent January 1, thereafter, by a number of shares equal to the lesser of (a) 5% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or (b) an amount determined by our board of directors. Furthermore, our Employee Stock Purchase Plan (“ESPP”) provides for annual increases in the number of shares available for issuance under our ESPP on January 1, 2020 and on each January 1, thereafter, by a number of shares equal to the smallest of (a) 1% of the number of shares of common stock issued and outstanding on the immediately preceding December 31, or (b) an amount determined by our board of directors. Effective January 1, 2021, our 2019 Plan reserve increased by 6,882,344 shares. Our board of directors determined not to increase the ESPP reserve in 2021. Common In 2014, we issued a warrant to purchase 56,875 shares of Series C convertible preferred stock at an exercise price of $2.64. The warrant was exercisable for a period of seven years from the date of issuance. Immediately prior to and in connection with the completion of our initial public offering on July 1, 2019, this convertible preferred stock warrant was converted to a warrant to purchase the same number of shares of common stock. The warrant was exercised on February 25, 2021 through a cashless exercise, resulting in the issuance of 54,162 shares of our common stock. The impact of this cashless exercise was immaterial to our unaudited condensed consolidated financial statements. As of March 31, 2021, there were no outstanding warrants to purchase common stock.

Equity Incentive Plans

Equity Incentive Plans	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity Incentive Plans	1 1 . Equity Incentive Plans Adaptive 2009 Equity Incentive Plan We adopted an equity incentive plan in 2009 (“2009 Plan”) that provided for the issuance of incentive and nonqualified common stock options and other share-based awards for employees, directors and consultants. Under the 2009 Plan, the option exercise price for incentive and nonqualified stock options were not to be less than the fair market value of our common stock at the date of grant. Options granted under this plan expire no later than ten years from the grant date and vesting was established at the time of grant. Pursuant to the terms of the 2019 Plan, any shares subject to outstanding options originally granted under the 2009 Plan that terminate, expire or lapse for any reason without the delivery of shares to the holder thereof shall become available for issuance pursuant to awards granted under the 2019 Plan. While no shares are available for future issuance under the 2009 Plan, it continues to govern outstanding equity awards granted thereunder. 2019 Equity Incentive Plan The 2019 Plan became effective immediately prior to the closing of our initial public offering in July 2019. The 2019 Plan provides for the issuance of awards in the form of options and other share-based awards for employees, directors and consultants. Under the 2019 Plan, the option exercise price per share shall not be less than the fair market value of a share of stock on the grant date of the option, as defined by the 2019 Plan, unless explicitly qualified under the provisions of Section 409A or Section 424(a) of the Internal Revenue Code of 1986. Additionally, unless otherwise specified, options granted under this plan expire no later than ten years from the grant date and vesting is established at the time of grant. Except for certain option and restricted stock unit grants made to non-employee directors, stock options and restricted stock units granted under the 2019 Plan generally vest over a four-year Changes in shares available for grant during the three months ended March 31, 2021 were as follows: Shares Available for Grant Shares available for grant at December 31, 2020 18,617,001 2019 Plan reserve increase on January 1, 2021 6,882,344 Options and restricted stock units granted (2,240,923 ) Options and restricted stock units forfeited, cancelled or expired 342,310 Shares available for grant at March 31, 2021 23,600,732 Stock option activity under the 2009 Plan and 2019 Plan during the three months ended March 31, 2021 was as follows: Shares Subject to Outstanding Options Weighted-Average Exercise Price per Share Aggregate Intrinsic Value (in thousands) Options outstanding at December 31, 2020 14,433,560 $ 12.82 $ 668,458 Options granted 1,635,608 45.33 Options forfeited or cancelled (328,594 ) 15.47 Options expired (10,050 ) 0.19 Options exercised (2,183,640 ) 6.61 Options outstanding at March 31, 2021 13,546,884 $ 17.69 $ 319,063 Options vested and exercisable at March 31, 2021 6,853,224 $ 8.56 $ 217,592 The weighted-average remaining contractual life for options outstanding as of March 31, 2021 was 7.2 years. The weighted-average remaining contractual life for vested and exercisable options outstanding as of March 31, 2021 was 5.7 years. As of March 31, 2021, $0.5 million was included in the prepaid expenses and other current assets line item on our unaudited condensed consolidated balance sheet for unsettled cash proceeds related to options exercised during the three months ended March 31, 2021. Of the $14.2 million proceeds from exercise of stock options included on our unaudited condensed consolidated statements of cash flows for the three months ended March 31, 2021, $0.3 million related to options exercised prior to but settled during the three months ended March 31, 2021. Of the $5.0 million proceeds from exercise of stock options included on our unaudited condensed consolidated statements of cash flows for the three months ended March 31, 2020, $0.5 million related to options exercised prior to but settled during the three months ended March 31, 2020. Restricted stock unit activity under the 2019 Plan during the three months ended March 31, 2021 was as follows: Restricted Stock Units Outstanding Weighted-Average Grant Date Nonvested outstanding restricted stock units at December 31, 2020 50,000 $ 28.10 Restricted stock units granted 605,315 44.10 Restricted stock units forfeited or cancelled (3,666 ) 62.40 Nonvested outstanding restricted stock units at March 31, 2021 651,649 $ 42.77 Grant Date Fair Value of Options and Restricted Stock Units Granted The estimated grant date fair value of options granted during the three months ended March 31, 2021 and 2020 was estimated using the Black-Scholes option-pricing model with the following assumptions: Three Months Ended March 31, 2021 2020 Fair value of common stock $43.68 - $66.50 $17.68 - $31.71 Expected term (in years) 5.27 - 6.08 5.27 - 6.08 Risk-free interest rate 0.5% - 1.1% 0.7% - 1.7% Expected volatility 67.1% - 68.4% 70.5% - 72.1% Expected dividend yield — — The weighted-average volatility used in the grant date fair value calculations of options granted during the three months ended March 31, 2021 and 2020 was 68.2% and 70.7%, respectively. The determination of the grant date fair value of stock options using a Black-Scholes option-pricing model is affected by the fair value of our common stock, as well as assumptions regarding a number of variables that are complex, subjective and generally require significant judgment to determine. The valuation assumptions were determined as follows: Fair value of common stock— The fair value of each share of common stock is based on the closing price of our common stock on the date of grant, or other relevant determination date, as reported on The Nasdaq Global Select Market. Expected term —The expected term of options granted to employees and non-employee directors is determined using the “simplified” method, as illustrated in ASC Topic 718, , as we do not have sufficient exercise history to determine a better estimate of expected term. Under this approach, the expected term is based on the midpoint between the vesting date and the end of the contractual term of the option. Risk-free interest rate —We utilize a risk-free interest rate in the option valuation model based on U.S. Treasury zero-coupon issues with remaining terms similar to the expected terms of the options. Expected volatility —As we do not have sufficient trading history for our common stock, the expected volatility is based on the historical volatility of our publicly traded industry peers utilizing a period of time consistent with our estimate of the expected term. Expected dividend yield —We do not anticipate paying any cash dividends in the foreseeable future and, therefore, use an expected dividend yield of zero in the option valuation model. The grant date fair value of restricted stock units granted is based on the closing price of our common stock on the date of grant, or other relevant determination date, as reported on The Nasdaq Global Select Market. Share-based compensation expense of $8.5 million and $4.7 million was recognized during the three months ended March 31, 2021 and 2020, respectively. The compensation costs related to stock options and restricted stock units for the three months ended March 31, 2021 and 2020 are included on our statements of operations as follows (in thousands): Three Months Ended March 31, 2021 2020 Cost of revenue $ 328 $ 172 Research and development 2,883 1,544 Sales and marketing 2,495 1,157 General and administrative 2,778 1,802 Total share-based compensation expense $ 8,484 $ 4,675 As of March 31, 2021, unrecognized share-based compensation expense related to unvested stock options was $109.1 million, which is expected to be recognized over a remaining weighted-average period of 3.2 years. Additionally, as of March 31, 2021, unrecognized share-based compensation expense related to unvested restricted stock units was $27.0 million, which is expected to be recognized over a remaining weighted-average period of 3.8 years.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Shareholders	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Shareholders	1 2 . Net Loss Shareholders The following table sets forth the computation of the basic and diluted net loss per share attributable to common shareholders for the three months ended March 31, 2021 and 2020 (in thousands, except share and per share amounts): Three Months Ended March 31, 2021 2020 Net loss $ (40,642 ) $ (31,403 ) Weighted-average shares used in computing net loss per share 138,967,754 126,058,389 Net loss per share attributable to common shareholders, basic and diluted $ (0.29 ) $ (0.25 ) Since we were in a loss position for all periods presented, basic net loss per share attributable to common shareholders is the same as diluted net loss per share attributable to common shareholders, as the inclusion of all potential shares of common stock outstanding would have been anti-dilutive. The following weighted-average common stock equivalents were excluded from the calculation of diluted net loss per share attributable to common shareholders for the three months ended March 31, 2021 and 2020, as they had an anti-dilutive effect: Three Months Ended March 31, 2021 2020 Stock options issued and outstanding 13,516,949 16,823,569 Nonvested restricted stock units 238,583 3,618 Common stock warrant 34,757 56,875 Total 13,790,289 16,884,062

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation and Use of Estimates	Basis The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures at the date of the financial statements, as well as the reported amounts of revenues and expenses during the periods presented. We base our estimates on historical experience and other relevant assumptions that we believe to be reasonable under the circumstances. Estimates are used in several areas including, but not limited to, estimates of progress to date for certain performance obligations and the transaction price for certain contracts with customers, share-based compensation, the provision for income taxes, including related reserves, and goodwill, among others. These estimates generally involve complex issues and require judgments, involve the analysis of historical results and prediction of future trends, can require extended periods of time to resolve and are subject to change from period to period. Actual results may differ materially from management’s estimates.
Unaudited Interim Condensed Consolidated Financial Statements	Unaudited Interim Condensed Consolidated Financial Statements In our opinion, the accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. These unaudited condensed consolidated financial statements include all adjustments necessary to fairly state the financial position and the results of our operations and cash flows for interim periods in accordance with GAAP. All such adjustments are of a normal, recurring nature. Interim-period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited financial statements and notes included in our Annual Report on Form 10-K for the year ended December 31, 2020 filed with the SEC on February 24, 2021.
Restricted Cash	Restricted Cash We are required to maintain certain balances under lease arrangements for some of our property and facility leases. We had restricted cash of $2.1 million as of March 31, 2021 and December 31, 2020.
Leases	Leases We determine if an arrangement contains a lease at inception. We have operating lease agreements for the laboratory and office facilities that we occupy, as well as server space. Operating lease right-of-use (“ROU”) assets and operating lease liabilities are recognized at the date the underlying asset becomes available for our use and are based on the present value of the future minimum lease payments over the lease term. ROU assets also include any initial direct costs incurred and any lease payments made at or before the lease commencement date, less lease incentives received. As our leases generally do not provide an implicit interest rate, the present value of our future minimum lease payments is determined using our incremental borrowing rate. This rate is an estimate of the collateralized borrowing rate we would incur on our future lease payments over a similar term and is based on the information available to us at the lease commencement date, or as of January 1, 2020 for commenced leases that existed as of our adoption of the new lease standard. Certain of our leases contain options to extend or terminate the lease; lease terms are adjusted for these options only when it is reasonably certain we will exercise these options. Our lease agreements do not contain residual value guarantees or covenants. We have made a policy election regarding our real estate leases not to separate nonlease components from lease components, to the extent they are fixed. Nonlease components that are not fixed are expensed as incurred as variable lease expense. Our leases for laboratory and office facilities typically include variable nonlease components, such as common-area maintenance costs. We have also elected not to record on the balance sheet a lease that has a lease term of twelve months or less and does not contain a purchase option that we are reasonably certain to exercise. Lease expense is recognized on a straight-line basis over the terms of the leases. Incentives granted under our facilities leases, including rent holidays, are recognized as adjustments to lease expense on a straight-line basis over the terms of the leases.
Concentrations of Risk	Concentrations We are subject to a concentration of risk from a limited number of suppliers, or in some cases single suppliers, for some of our laboratory instruments and materials. This risk is managed by targeting a quantity of surplus stock. Cash, cash equivalents and marketable securities are financial instruments that potentially subject us to concentrations of credit risk. We invest in money market funds, United States (“U.S.”) government debt securities, U.S. government agency securities, commercial paper and corporate bonds with high-quality accredited financial institutions. Significant customers are those that represent more than 10% of our total revenue or accounts receivable, net balances for the periods and as of each balance sheet date presented, respectively. Revenue from these customers reflects their purchase of our products and services and our collaboration efforts with Genentech. For each significant customer, revenue as a percentage of total revenue for the periods presented and accounts receivable, net as a percentage of total accounts receivable, net as of the dates presented were as follows: Revenue Accounts Receivable, Net Three Months Ended March 31, March 31, December 31, 2021 2020 2021 2020 Customer A *% *% *% 19.1 % Customer B 10.4 * 17.8 12.2 Customer D 10.0 * 19.4 * Customer E * * 17.8 * Genentech, Inc. and Roche Group 42.1 54.4 * * * less than 10%
Revenue Recognition	Revenue We recognize revenue in accordance with Accounting Standards Codification (“ASC”) Topic 606 (“ASC 606”), Revenue from Contracts with Customers Overview Our revenue is generated from immunosequencing (“sequencing”) products and services (“sequencing revenue”) and from regulatory or development support services leveraging our immune medicine platform (“development revenue”). When revenue generating contracts have elements of both sequencing revenue and development revenue, we classify revenue based on the nature of the performance obligation and the allocated transaction price. Sequencing Revenue Sequencing revenue reflects the amounts generated from providing sequencing services and testing through our clonoSEQ and immunoSEQ products and services to our clinical and research customers, respectively. For clinical customers, we derive revenues from providing our clonoSEQ report to ordering physicians, and we bill and receive payments from medical institutions and commercial and government third-party payors. In these transactions, we have identified one performance obligation: the delivery of a clonoSEQ report. As payment from the respective payors may vary based on the various reimbursement rates and patient responsibilities, we consider the transaction price to be variable and record an estimate of the transaction price, subject to the constraint for variable consideration, as revenue at the time of delivery. The estimate of transaction price is based on historical and expected reimbursement rates with the various payors, which are monitored in subsequent periods and adjusted as necessary based on actual collection experience. For our clonoSEQ coverage under Medicare, we bill an episode of treatment when we deliver the first eligible test results. This billing contemplates all necessary tests required during a patient’s treatment cycle, which is currently estimated at approximately four tests per patient, including the initial sequence identification test. Revenue recognition commences at the time the initial billable test result is delivered and is based upon cumulative tests delivered to date. We estimate the number of tests we expect to deliver over a patient’s treatment cycle based on historical testing frequencies for patients by indication. These estimates are subject to change as we develop more information about utilization over time. Any unrecognized revenue from the initial billable test is recorded as deferred revenue and is recognized as we deliver the remaining tests in a patient’s treatment cycle or when it becomes remote that a patient will receive additional testing and we have not delivered our estimate of total tests. For research customers, contracts typically include an amount billed in advance of services (“upfront”) and subsequent billings as sample results are delivered to the customer. Upfront amounts received are recorded as deferred revenue, which we recognize as revenue upon satisfaction of performance obligations. We have identified two typical performance obligations under the terms of our research service contracts: sequencing services and related data analysis. We recognize revenue for both identified performance obligations as sample results are delivered to the customer. Development We derive revenue by providing services through development agreements to biopharmaceutical customers who seek access to our immune medicine platform technologies. We generate revenues from the delivery of professional support activities pertaining to the use of immunoSEQ and our minimal residual disease (“MRD”) product in the development of the respective customers’ initiatives. The transaction price for these contracts may consist of a combination of non-refundable upfront fees, separately priced sequencing fees, progress-based milestones and regulatory milestones. The development agreements may include single or multiple performance obligations, depending on the contract. For certain contracts, we may perform services to support the biopharmaceutical customers’ regulatory submissions as part of their registrational trials. These services include regulatory support pertaining to our technology intended to be utilized as part of the submission, development of analytical plans for our sequencing data, participation on joint research committees and assistance in completing a regulatory submission. Generally, these services are not distinct within the context of the contract and they are accounted for as a single performance obligation. When sequencing services are separately priced customer options, we assess if a material right exists and, if not, the customer option to purchase additional sequencing services is not considered part of the contract. Except for any non-refundable upfront fees, the other forms of compensation represent variable consideration. Variable consideration related to progress - based and regulatory milestones is estimated using the most likely amount method , where variable consideration is constrained until it is probable that a significant reversal of cumulative revenue recognized will not occur. Progress milestones , such as the first sample result delivered or final patient enrollment in a customer trial , are customer dependent and are included in the transaction price when the respective milestone is probable of occurring. Milestone payments that are not within our customers’ control, such as regulatory approvals, are not consider ed probable of being achieved until those approvals are received. Determining whether regulatory milestone payments are probable is an area that requires significant judgment. In making this assessment, we evaluate scientific, clinical, regulatory and other risks, as well as the level of effort and investment required to achieve the respective milestone. The primary method used to estimate standalone selling price for performance obligations is the adjusted market assessment approach. Using this approach, we evaluate the market in which we sell our services and estimate the price that a customer in that market would be willing to pay for our services. We recognize revenue using either an input or output measure of progress that faithfully depicts performance on a contract, depending on the contract. The measure used is dependent on the nature of the service to be provided in each contract. Selecting the measure of progress and estimating progress to date requires significant judgment.
Net Loss Per Share Attributable to Common Shareholders	Net Loss Per Share Attributable to Common Shareholders We calculate basic net loss per share attributable to common shareholders by dividing the net loss attributable to common shareholders by the weighted-average number of shares of common stock outstanding for the period. The diluted net loss per share attributable to common shareholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period determined using the treasury stock method. For purposes of this calculation, common stock warrants, stock options and nonvested restricted stock units are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common shareholders, as their effect is anti-dilutive.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Schedule of Concentrations of Risk Percentage	For each significant customer, revenue as a percentage of total revenue for the periods presented and accounts receivable, net as a percentage of total accounts receivable, net as of the dates presented were as follows: Revenue Accounts Receivable, Net Three Months Ended March 31, March 31, December 31, 2021 2020 2021 2020 Customer A *% *% *% 19.1 % Customer B 10.4 * 17.8 12.2 Customer D 10.0 * 19.4 * Customer E * * 17.8 * Genentech, Inc. and Roche Group 42.1 54.4 * * * less than 10%

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables set forth the fair value of financial assets as of March 31, 2021 and December 31, 2020 that were measured at fair value on a recurring basis (in thousands): March 31, 2021 Level 1 Level 2 Level 3 Total Financial assets Money market funds $ 151,330 $ — $ — $ 151,330 U.S. government debt securities — 559,788 — 559,788 Corporate bonds — 11,540 — 11,540 Total financial assets $ 151,330 $ 571,328 $ — $ 722,658 December 31, 2020 Level 1 Level 2 Level 3 Total Financial assets Money market funds $ 103,283 $ — $ — $ 103,283 U.S. government debt securities — 671,777 — 671,777 Corporate bonds — 11,581 — 11,581 Total financial assets $ 103,283 $ 683,358 $ — $ 786,641

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Schedule of Available-for-sale Investments	Available-for-sale investments consisted of the following as of March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Short-term marketable securities U.S. government debt securities $ 528,522 $ 578 $ — $ 529,100 Corporate bonds 11,494 46 — 11,540 Total short-term marketable securities $ 540,016 $ 624 $ — $ 540,640 Long-term marketable securities U.S. government debt securities $ 30,681 $ 10 $ (3 ) $ 30,688 Total long-term marketable securities $ 30,681 $ 10 $ (3 ) $ 30,688 December 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Short-term marketable securities U.S. government debt securities $ 552,539 $ 723 $ (10 ) $ 553,252 Corporate bonds 11,497 86 (2 ) 11,581 Total short-term marketable securities $ 564,036 $ 809 $ (12 ) $ 564,833 Long-term marketable securities U.S. government debt securities $ 118,429 $ 98 $ (2 ) $ 118,525 Total long-term marketable securities $ 118,429 $ 98 $ (2 ) $ 118,525
Schedule of Gross Unrealized Holding Losses and Fair Value for Investments in Unrealized Loss Position	The following table presents the gross unrealized holding losses and fair value for investments in an unrealized loss position, and the length of time that individual securities have been in a continuous loss position, as of March 31, 2021 (in thousands): Less Than 12 Months 12 Months Or Greater Fair Value Unrealized Loss Fair Value Unrealized Loss U.S. government debt securities $ 10,240 $ (3 ) $ — $ — Corporate bonds 1,503 — — — Total available-for-sale securities $ 11,743 $ (3 ) $ — $ —

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Intangible Assets Subject to Amortization	Intangible assets subject to amortization as of March 31, 2021 and December 31, 2020 consisted of the following (in thousands): March 31, 2021 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 20,000 $ (10,382 ) $ 9,618 Purchased intellectual property 325 (137 ) 188 Balance at March 31, 2021 $ 20,325 $ (10,519 ) $ 9,806 December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 20,000 $ (9,972 ) $ 10,028 Purchased intellectual property 325 (128 ) 197 Balance at December 31, 2020 $ 20,325 $ (10,100 ) $ 10,225
Schedule of Future Amortization Expense for Intangible Assets	As of March 31, 2021, expected future amortization expense for intangible assets was as follows (in thousands): 2021 (excluding the three months ended March 31, 2021) $ 1,280 2022 1,699 2023 1,699 2024 1,703 2025 1,699 Thereafter 1,726 Total future amortization expense $ 9,806

Deferred Revenue (Tables)

Deferred Revenue (Tables)	3 Months Ended
	Mar. 31, 2021
Revenue From Contract With Customer [Abstract]
Schedule of Deferred Revenue by Revenue Classification	Deferred revenue by revenue classification as of March 31, 2021 and December 31, 2020 was as follows (in thousands): March 31, 2021 December 31, 2020 Current deferred revenue Sequencing $ 17,191 $ 15,463 Development 61,157 57,856 Total current deferred revenue 78,348 73,319 Non-current deferred revenue Sequencing 662 724 Development 143,694 162,894 Total non-current deferred revenue 144,356 163,618 Total current and non-current deferred revenue $ 222,704 $ 236,937
Schedule of Changes in Deferred Revenue	Changes in deferred revenue during the three months ended March 31, 2021 were as follows (in thousands): Deferred revenue balance at December 31, 2020 $ 236,937 Additions to deferred revenue during the period 7,118 Revenue recognized during the period (21,351 ) Deferred revenue balance at March 31, 2021 $ 222,704

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2021
Lessee Disclosure [Abstract]
Summary of Other Information Related to Operating Lease	Other information related to our operating leases as of was as follows: Weighted-average remaining lease term (in years) 11.07 Weighted-average discount rate 4.6 %
Summary of Reconciles Undiscounted Operating Lease Cash Flows	The following table reconciles our undiscounted operating lease cash flows to our operating lease liabilities as of (in thousands): 2021 (excluding the three months ended March 31, 2021) $ 6,120 2022 13,554 2023 13,318 2024 13,030 2025 13,419 Thereafter 89,236 Total undiscounted lease payments 148,677 Less: Imputed interest rate (34,873 ) Tenant improvement receivables (14,244 ) Total operating lease liabilities $ 99,560 Less: current portion (4,308 ) Operating lease liabilities, less current portion $ 95,252

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Summary of Reserved Shares of Common Stock	As of March 31, 2021, we have reserved shares of common stock for the following: Shares issuable upon the exercise of outstanding common stock options and the vesting of outstanding common restricted stock units granted 14,198,533 Shares available for future grant under the 2019 Equity Incentive Plan 23,600,732 Shares available for future grant under the Employee Stock Purchase Plan 2,804,298 Total shares of common stock reserved for future issuance 40,603,563

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Changes in Shares Available for Grant	Changes in shares available for grant during the three months ended March 31, 2021 were as follows: Shares Available for Grant Shares available for grant at December 31, 2020 18,617,001 2019 Plan reserve increase on January 1, 2021 6,882,344 Options and restricted stock units granted (2,240,923 ) Options and restricted stock units forfeited, cancelled or expired 342,310 Shares available for grant at March 31, 2021 23,600,732
Summary of Stock Option Activity Under 2009 Plan and 2019 Plan	Stock option activity under the 2009 Plan and 2019 Plan during the three months ended March 31, 2021 was as follows: Shares Subject to Outstanding Options Weighted-Average Exercise Price per Share Aggregate Intrinsic Value (in thousands) Options outstanding at December 31, 2020 14,433,560 $ 12.82 $ 668,458 Options granted 1,635,608 45.33 Options forfeited or cancelled (328,594 ) 15.47 Options expired (10,050 ) 0.19 Options exercised (2,183,640 ) 6.61 Options outstanding at March 31, 2021 13,546,884 $ 17.69 $ 319,063 Options vested and exercisable at March 31, 2021 6,853,224 $ 8.56 $ 217,592
Summary of Restricted Stock Unit Activity	Restricted stock unit activity under the 2019 Plan during the three months ended March 31, 2021 was as follows: Restricted Stock Units Outstanding Weighted-Average Grant Date Nonvested outstanding restricted stock units at December 31, 2020 50,000 $ 28.10 Restricted stock units granted 605,315 44.10 Restricted stock units forfeited or cancelled (3,666 ) 62.40 Nonvested outstanding restricted stock units at March 31, 2021 651,649 $ 42.77
Summary of Estimated Grant Date Fair Value of Options Granted	The estimated grant date fair value of options granted during the three months ended March 31, 2021 and 2020 was estimated using the Black-Scholes option-pricing model with the following assumptions: Three Months Ended March 31, 2021 2020 Fair value of common stock $43.68 - $66.50 $17.68 - $31.71 Expected term (in years) 5.27 - 6.08 5.27 - 6.08 Risk-free interest rate 0.5% - 1.1% 0.7% - 1.7% Expected volatility 67.1% - 68.4% 70.5% - 72.1% Expected dividend yield — —
Summary of Compensation Costs Related to Stock Options and RSUs Included on Statements of Operations	The compensation costs related to stock options and restricted stock units for the three months ended March 31, 2021 and 2020 are included on our statements of operations as follows (in thousands): Three Months Ended March 31, 2021 2020 Cost of revenue $ 328 $ 172 Research and development 2,883 1,544 Sales and marketing 2,495 1,157 General and administrative 2,778 1,802 Total share-based compensation expense $ 8,484 $ 4,675

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Shareholders (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Computation of the Basic and Diluted Net Loss Per Share Attributable to Common Shareholders	The following table sets forth the computation of the basic and diluted net loss per share attributable to common shareholders for the three months ended March 31, 2021 and 2020 (in thousands, except share and per share amounts): Three Months Ended March 31, 2021 2020 Net loss $ (40,642 ) $ (31,403 ) Weighted-average shares used in computing net loss per share 138,967,754 126,058,389 Net loss per share attributable to common shareholders, basic and diluted $ (0.29 ) $ (0.25 )
Weighted-Average Common Stock Equivalents were Excluded From Calculation of Diluted Net Loss Per Share Attributable to Common Shareholders	The following weighted-average common stock equivalents were excluded from the calculation of diluted net loss per share attributable to common shareholders for the three months ended March 31, 2021 and 2020, as they had an anti-dilutive effect: Three Months Ended March 31, 2021 2020 Stock options issued and outstanding 13,516,949 16,823,569 Nonvested restricted stock units 238,583 3,618 Common stock warrant 34,757 56,875 Total 13,790,289 16,884,062

Organization and Description _2

Organization and Description of Business - Additional Information (Details)	Mar. 31, 2021
Spin Technologies, Inc.
Subsidiary Or Equity Method Investee [Line Items]
Ownership interest percentage	70.00%

Significant Accounting Polici_4

Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)Performance_Obligation	Dec. 31, 2020USD ($)
Significant Accounting Policies [Line Items]
Restricted cash | $	$ 2,138	$ 2,138
Sequencing Revenue
Significant Accounting Policies [Line Items]
Number of revenue performance obligations | Performance_Obligation	2

Significant Accounting Polici_5

Significant Accounting Policies - Schedule of Concentrations of Risk Percentage (Details) - Customer Concentration Risk	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Customer A | Accounts Receivable, Net
Significant Accounting Policies [Line Items]
Concentration risk, percentage			19.10%
Customer B | Revenue
Significant Accounting Policies [Line Items]
Concentration risk, percentage	10.40%
Customer B | Accounts Receivable, Net
Significant Accounting Policies [Line Items]
Concentration risk, percentage	17.80%		12.20%
Customer D | Revenue
Significant Accounting Policies [Line Items]
Concentration risk, percentage	10.00%
Customer D | Accounts Receivable, Net
Significant Accounting Policies [Line Items]
Concentration risk, percentage	19.40%
Customer E | Accounts Receivable, Net
Significant Accounting Policies [Line Items]
Concentration risk, percentage	17.80%
Genentech, Inc. and Roche Group | Revenue
Significant Accounting Policies [Line Items]
Concentration risk, percentage	42.10%	54.40%

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($)	Mar. 31, 2021	Feb. 28, 2019	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Revenue recognized	$ 19,000,000		$ (21,351,000)
Revenue from collaboration agreement			38,442,000	$ 20,910,000
MRD Development Agreements
Disaggregation Of Revenue [Line Items]
Milestone revenue recognized			7,000,000
Revenue recognized			7,200,000	400,000
MRD Development Agreements | Maximum
Disaggregation Of Revenue [Line Items]
Additional milestone payment receivable	306,500,000		306,500,000
Genentech Collaboration Agreement
Disaggregation Of Revenue [Line Items]
Non-refundable upfront payments received		$ 300,000,000	300,000,000
Revenue from collaboration agreement			$ 15,600,000	$ 10,900,000
Genentech Collaboration Agreement | Maximum
Disaggregation Of Revenue [Line Items]
Revenue recognition expected period			8 years
Genentech Collaboration Agreement | Maximum | Regulatory Milestones
Disaggregation Of Revenue [Line Items]
Expected revenue through milestone payments	75,000,000		$ 75,000,000
Genentech Collaboration Agreement | Maximum | Development Milestones
Disaggregation Of Revenue [Line Items]
Expected revenue through milestone payments	300,000,000		300,000,000
Genentech Collaboration Agreement | Maximum | Commercial Milestones
Disaggregation Of Revenue [Line Items]
Expected revenue through milestone payments	1,430,000,000		1,430,000,000
Genentech Collaboration Agreement | Minimum
Disaggregation Of Revenue [Line Items]
Expected revenue through milestone payments	$ 1,800,000		$ 1,800,000
Revenue recognition expected period			7 years

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring basis - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets
Total financial assets	$ 722,658	$ 786,641
Level 1
Financial assets
Total financial assets	151,330	103,283
Level 2
Financial assets
Total financial assets	571,328	683,358
Money Market Funds
Financial assets
Total financial assets	151,330	103,283
Money Market Funds | Level 1
Financial assets
Total financial assets	151,330	103,283
U.S. Government Debt Securities
Financial assets
Total financial assets	559,788	671,777
U.S. Government Debt Securities | Level 2
Financial assets
Total financial assets	559,788	671,777
Corporate Bonds
Financial assets
Total financial assets	11,540	11,581
Corporate Bonds | Level 2
Financial assets
Total financial assets	$ 11,540	$ 11,581

Investments - Schedule of Avail

Investments - Schedule of Available-for-sale Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Short-Term Marketable Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	$ 540,016	$ 564,036
Unrealized Gain	624	809
Unrealized Loss		(12)
Estimated Fair Value	540,640	564,833
Long-Term Marketable Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	30,681	118,429
Unrealized Gain	10	98
Unrealized Loss	(3)	(2)
Estimated Fair Value	30,688	118,525
U.S. Government Debt Securities | Short-Term Marketable Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	528,522	552,539
Unrealized Gain	578	723
Unrealized Loss		(10)
Estimated Fair Value	529,100	553,252
U.S. Government Debt Securities | Long-Term Marketable Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	30,681	118,429
Unrealized Gain	10	98
Unrealized Loss	(3)	(2)
Estimated Fair Value	30,688	118,525
Corporate Bonds | Short-Term Marketable Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	11,494	11,497
Unrealized Gain	46	86
Unrealized Loss		(2)
Estimated Fair Value	$ 11,540	$ 11,581

Investments - Additional Inform

Investments - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Prepaid Expenses and Other Current Assets
Schedule of Available-for-Sale Securities [Line Items]
Accrued interest receivables	$ 2.8	$ 2.5

Investments - Schedule of Gross

Investments - Schedule of Gross Unrealized Holding Losses and Fair Value for Investments in Unrealized Loss Position (Details) $ in Thousands	Mar. 31, 2021USD ($)
Schedule of Available-for-Sale Securities [Line Items]
Less than 12 months, Fair value	$ 11,743
Less than 12 months, Unrealized loss	(3)
U.S. Government Debt Securities
Schedule of Available-for-Sale Securities [Line Items]
Less than 12 months, Fair value	10,240
Less than 12 months, Unrealized loss	(3)
Corporate Bonds
Schedule of Available-for-Sale Securities [Line Items]
Less than 12 months, Fair value	$ 1,503

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2015
Goodwill [Line Items]
Goodwill	$ 118,972,000	$ 118,972,000	$ 0
Purchased Intellectual Property
Goodwill [Line Items]
Amortization period of intangible assets	5 years 9 months 18 days

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Summary of Intangible Assets Subject to Amortization (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 20,325	$ 20,325
Accumulated Amortization	(10,519)	(10,100)
Net Carrying Amount	9,806	10,225
Acquired Developed Technology
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	20,000	20,000
Accumulated Amortization	(10,382)	(9,972)
Net Carrying Amount	9,618	10,028
Purchased Intellectual Property
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	325	325
Accumulated Amortization	(137)	(128)
Net Carrying Amount	$ 188	$ 197

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Future Amortization Expense for Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
2021 (excluding the three months ended March 31, 2021)	$ 1,280
2022	1,699
2023	1,699
2024	1,703
2025	1,699
Thereafter	1,726
Net Carrying Amount	$ 9,806	$ 10,225

Deferred Revenue - Schedule of

Deferred Revenue - Schedule of Deferred Revenue by Revenue Classification (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current deferred revenue
Total current deferred revenue	$ 78,348	$ 73,319
Non-current deferred revenue
Total non-current deferred revenue	144,356	163,618
Total current and non-current deferred revenue	222,704	236,937
Sequencing Revenue
Current deferred revenue
Total current deferred revenue	17,191	15,463
Non-current deferred revenue
Total non-current deferred revenue	662	724
Development Revenue
Current deferred revenue
Total current deferred revenue	61,157	57,856
Non-current deferred revenue
Total non-current deferred revenue	$ 143,694	$ 162,894

Deferred Revenue - Additional I

Deferred Revenue - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Disaggregation Of Revenue [Line Items]
Current deferred revenue	$ 78,348	$ 78,348		$ 73,319
Deferred revenue, less current portion	144,356	144,356		163,618
Revenue recognized	19,000	(21,351)
MRD Development Agreements
Disaggregation Of Revenue [Line Items]
Revenue recognized		7,200	$ 400
Development Revenue
Disaggregation Of Revenue [Line Items]
Current deferred revenue	61,157	61,157		57,856
Deferred revenue, less current portion	143,694	143,694		162,894
Development Revenue | Genentech, Inc.
Disaggregation Of Revenue [Line Items]
Current deferred revenue	58,600	58,600		55,100
Deferred revenue, less current portion	137,900	137,900		157,000
Sequencing Revenue
Disaggregation Of Revenue [Line Items]
Current deferred revenue	17,191	17,191		15,463
Deferred revenue, less current portion	$ 662	662		724
Revenue recognized		200
Medicare | Specific Patients
Disaggregation Of Revenue [Line Items]
Revenue recognized				$ 200
Anticipated Samples | MRD Development Agreements
Disaggregation Of Revenue [Line Items]
Revenue recognized		$ 400

Deferred Revenue - Additional_2

Deferred Revenue - Additional Information (Details1) - Genentech, Inc. - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-04-01	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Deferred revenue, expected to be recognized	12 months
Minimum
Disaggregation Of Revenue [Line Items]
Deferred revenue, expected to be recognized	5 years
Maximum
Disaggregation Of Revenue [Line Items]
Deferred revenue, expected to be recognized	6 years

Deferred Revenue - Schedule o_2

Deferred Revenue - Schedule of Changes in Deferred Revenue (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2021
Revenue From Contract With Customer [Abstract]
Deferred revenue balance at December 31, 2020		$ 236,937
Additions to deferred revenue during the period		7,118
Revenue recognized during the period	$ 19,000	(21,351)
Deferred revenue balance at March 31, 2021	$ 222,704	$ 222,704

Leases- Additional Information

Leases- Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)ft²Lease	Mar. 31, 2020USD ($)
Lessee Lease Description [Line Items]
Lessee, operating lease, option to extend	options to extend certain of the leases up to 10.0 years
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Operating lease renewal term	10 years
Operating lease termination period	3 years
Number of operating lease terminate | Lease	2
Letter of credit	$ 2.1
Operating lease expense	3.1	$ 1.1
Operating lease variable lease expense	0.7	0.5
Cash paid for amounts included in measurement of lease liabilities, net of tenant improvement allowances received	0.5	0.8
Cash received for tenant improvement allowances	$ 1.2	$ 0.3
Number of square feet | ft²	27,000
Lessee, operating lease, lease not yet commenced description	Rent obligations commence six months after lease commencement and the lease expires 120 months thereafter, subject to an early termination option after the seventh year and an option to twice extend the lease for five years. This lease will be assessed for classification and a lease liability and corresponding ROU asset will be recorded upon lease commencement. Future non-cancellable undiscounted lease payments, exclusive of operating and maintenance costs, total
Rent obligations, commencement term	6 months
Lease not yet commenced, expiration term thereafter	120 months
Lease not yet commenced, termination option description	subject to an early termination option after the seventh year
Lease not yet commenced, option to extend description	option to twice extend the lease for five years
Lease not yet commenced, option to extend term	5 years
Operating lease, lease liability upon lease commencement	$ 7
Lease not yet commenced landlord agreed to fund for improvements	$ 1.2
Minimum
Lessee Lease Description [Line Items]
Operating lease remaining lease term	1 year 1 month 6 days
Maximum
Lessee Lease Description [Line Items]
Operating lease remaining lease term	12 years 4 months 24 days

Leases- Summary of Oher Informa

Leases- Summary of Oher Information Related to Operating Lease (Details)	Mar. 31, 2021
Lessee Disclosure [Abstract]
Weighted-average remaining lease term (in years)	11 years 25 days
Weighted-average discount rate	4.60%

Leases- Summary of Reconciles U

Leases- Summary of Reconciles Undiscounted Operating Lease Cash Flows (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Lessee Disclosure [Abstract]
2021 (excluding the three months ended March 31, 2021)	$ 6,120
2022	13,554
2023	13,318
2024	13,030
2025	13,419
Thereafter	89,236
Total undiscounted lease payments	148,677
Imputed interest rate	(34,873)
Tenant improvement receivables	(14,244)
Total operating lease liabilities	99,560
Less: current portion	(4,308)	$ (3,529)
Operating lease liabilities, less current portion	$ 95,252	$ 104,333

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Details)	Feb. 25, 2021shares	Jan. 01, 2021shares	Jan. 01, 2020	Mar. 31, 2021Vote$ / sharesshares	Dec. 31, 2014$ / sharesshares	Dec. 31, 2020$ / sharesshares
Class Of Stock [Line Items]
Preferred stock, shares authorized				10,000,000		10,000,000
Preferred stock, par value | $ / shares				$ 0.0001		$ 0.0001
Preferred stock, shares outstanding				0		0
Common stock authorized				340,000,000		340,000,000
Common stock par value | $ / shares				$ 0.0001		$ 0.0001
Common stock voting rights description				Holders of our common stock are entitled to one vote for each share of common stock held
Number of vote for each share | Vote				1
Common stock outstanding				139,884,698		137,646,896
Warrant issued to purchase stock				0
Series C Convertible Preferred Stock
Class Of Stock [Line Items]
Warrant issued to purchase stock					56,875
Warrant exercisable term					7 years
Weighted-average exercise price of warrants | $ / shares					$ 2.64
Common Stock
Class Of Stock [Line Items]
Stock issued during period, common stock	54,162			54,162
Maximum | Employee Stock Purchase Plan
Class Of Stock [Line Items]
Percentage of annual increases in number of shares			1.00%
2019 Equity Incentive Plan
Class Of Stock [Line Items]
Increase in share reserve		6,882,344
2019 Equity Incentive Plan | Maximum
Class Of Stock [Line Items]
Percentage of annual increases in number of shares			5.00%

Shareholders' Equity - Summary

Shareholders' Equity - Summary of Reserved Shares of Common Stock (Details)	Mar. 31, 2021shares
Class Of Stock [Line Items]
Total shares of common stock reserved for future issuance	40,603,563
Exercise of Outstanding Common Stock Options and Vesting of Outstanding Common Restricted Stock Units Granted
Class Of Stock [Line Items]
Total shares of common stock reserved for future issuance	14,198,533
Grant | 2019 Equity Incentive Plan
Class Of Stock [Line Items]
Total shares of common stock reserved for future issuance	23,600,732
Grant | Employee Stock Purchase Plan
Class Of Stock [Line Items]
Total shares of common stock reserved for future issuance	2,804,298

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining contractual life options outstanding	7 years 2 months 12 days
Weighted-average remaining contractual life vested and exercisable options outstanding	5 years 8 months 12 days
Proceeds from exercise of stock options	$ 14,185	$ 4,959
Proceeds from settlement of stock option exercised in prior periods	$ 300
Weighted-average volatility	68.20%	70.70%
Share-based compensation expense	$ 8,484	$ 4,675
Unrecognized share-based compensation expense related to unvested stock options	$ 109,100
Unrecognized share-based compensation expense related to unvested stock options, weighted-average period for recognition	3 years 2 months 12 days
Option Valuation Model
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense related to unvested stock options, weighted-average period for recognition	3 years 9 months 18 days
Unrecognized share-based compensation expense related to unvested RSUs	$ 27,000
2009 Equity Incentive Plan | Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	0
2009 Equity Incentive Plan | Grant | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period	10 years
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	23,600,732		18,617,001
2019 Equity Incentive Plan | Non Employee Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
2019 Equity Incentive Plan | Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized for issuance	29,148,701
2019 Equity Incentive Plan | Grant | Prepaid Expenses and Other Current Assets
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unsettled cash proceeds related to stock options exercised		$ 500
2019 Equity Incentive Plan | Grant | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period	10 years
2019 Equity Incentive Plan | Restricted Stock Units | Prepaid Expenses and Other Current Assets
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unsettled cash proceeds related to stock options exercised	$ 500

Equity Incentive Plans - Summar

Equity Incentive Plans - Summary of Changes in Shares Available for Grant (Details) - 2019 Equity Incentive Plan	3 Months Ended
	Mar. 31, 2021shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares Available for Grant, Outstanding, Beginning Balance	18,617,001
Shares Available for Grant, 2019 Plan reserve increase	6,882,344
Shares Available for Grant, Options and restricted stock units granted	(2,240,923)
Shares Available for Grant, Options and restricted stock units forfeited, cancelled or expired	342,310
Shares Available for Grant, Outstanding, Ending Balance	23,600,732

Equity Incentive Plans - Summ_2

Equity Incentive Plans - Summary of Stock Option Activity Under 2009 Plan and 2019 Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares Subject to Outstanding Options, Options outstanding, Beginning Balance	14,433,560
Shares Subject to Outstanding Options, Options granted	1,635,608
Shares Subject to Outstanding Options, Options forfeited or cancelled	(328,594)
Shares Subject to Outstanding Options, Options expired	(10,050)
Shares Subject to Outstanding Options, Options exercised	(2,183,640)
Shares Subject to Outstanding Options, Options outstanding, Ending Balance	13,546,884
Shares Subject to Outstanding Options, Options vested and exercisable	6,853,224
Weighted Average Exercise Price per Share, Options outstanding, Beginning Balance	$ 12.82
Weighted Average Exercise Price per Share, Options granted	45.33
Weighted Average Exercise Price per Share, Options forfeited or cancelled	15.47
Weighted Average Exercise Price per Share, Options expired	0.19
Weighted Average Exercise Price per Share, Options exercised	6.61
Weighted Average Exercise Price per Share, Options outstanding, Ending Balance	17.69
Weighted Average Exercise Price per Share, Options vested and exercisable	$ 8.56
Aggregate Intrinsic Value, Option outstanding	$ 319,063	$ 668,458
Aggregate Intrinsic Value, Options vested and exercisable	$ 217,592

Equity Incentive Plans - Summ_3

Equity Incentive Plans - Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Units - 2019 Equity Incentive Plan	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Restricted Stock Units Outstanding
Restricted Stock Units Outstanding, Nonvested Outstanding, Beginning Balance | shares	50,000
Restricted Stock Units Outstanding, Granted | shares	605,315
Restricted Stock Units Outstanding, Forfeited or cancelled | shares	(3,666)
Restricted Stock Units Outstanding, Nonvested Outstanding, Ending Balance | shares	651,649
Weighted-Average Grant Date Fair Value per Share
Weighted-Average Grant Date Fair Value per Share, Nonvested Outstanding, Beginning Balance | $ / shares	$ 28.10
Weighted-Average Grant Date Fair Value per Share, Nonvested Outstanding, Granted | $ / shares	44.10
Weighted-Average Grant Date Fair Value per Share, Nonvested Outstanding, Forfeited or cancelled | $ / shares	62.40
Weighted-Average Grant Date Fair Value per Share, Nonvested Outstanding, Ending Balance | $ / shares	$ 42.77

Equity Incentive Plans - Summ_4

Equity Incentive Plans - Summary of Estimated Grant Date Fair Value of Options Granted (Details) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate, minimum	0.50%	0.70%
Risk-free interest rate, maximum	1.10%	1.70%
Expected volatility, minimum	67.10%	70.50%
Expected volatility, maximum	68.40%	72.10%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock	$ 43.68	$ 17.68
Expected term (in years)	5 years 3 months 7 days	5 years 3 months 7 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of common stock	$ 66.50	$ 31.71
Expected term (in years)	6 years 29 days	6 years 29 days

Equity incentive Plans - Summ_5

Equity incentive Plans - Summary of Compensation Costs Related to Stock Options and RSUS Included on Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 8,484	$ 4,675
Cost of Revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	328	172
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	2,883	1,544
Sales and Marketing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	2,495	1,157
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 2,778	$ 1,802

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Shareholders - Computation of the Basic and Diluted Net Loss Per Share Attributable to Common Shareholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (40,642)	$ (31,403)
Weighted-average shares used in computing net loss per share	138,967,754	126,058,389
Net loss per share attributable to common shareholders, basic and diluted	$ (0.29)	$ (0.25)

Net Loss Per Share Attributab_4

Net Loss Per Share Attributable to Common Shareholders - Weighted-Average Common Stock Equivalents were Excluded From Calculation of Diluted Net Loss Per Share Attributable to Common Shareholders (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities	13,790,289	16,884,062
Grant
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities	13,516,949	16,823,569
Nonvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities	238,583	3,618
Common Stock Warrant
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities	34,757	56,875