Quanterix (QTRX) 10-Q 6 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
Document Period End Date	Mar. 31, 2021
Entity Registrant Name	Quanterix Corp
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-38319
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8957988
Entity Address, Address Line One	900 Middlesex Turnpike
Entity Address, City or Town	Billerica
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01821
City Area Code	617
Local Phone Number	301-9400
Title of 12(g) Security	Common Stock, $0.001 par value per share
Trading Symbol	QTRX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		36,336,598
Entity Central Index Key	0001503274
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 442,672	$ 181,584
Accounts receivable (less allowance for credit losses of $342 and $370 as of March 31, 2021 and December 31, 2020, respectively; including $137 and $172 due from related parties as of March 31, 2021 and December 31, 2020, respectively)	14,936	17,184
Inventory	17,044	14,856
Prepaid expenses and other current assets	7,791	5,981
Total current assets	482,443	219,605
Restricted cash	1,400	1,000
Property and equipment, net	14,183	13,912
Intangible assets, net	12,464	13,716
Goodwill	9,933	10,460
Right-of-use assets	11,870	11,995
Other non-current assets	373	357
Total assets	532,666	271,045
Current liabilities:
Accounts payable (including $6 and $14 to related parties as of March 31, 2021 and December 31, 2020, respectively)	6,503	6,799
Accrued compensation and benefits	7,015	10,777
Other accrued expenses (including $4 and $1,377 to related parties as of March 31, 2021 and December 31, 2020, respectively)	5,603	4,845
Deferred revenue (including $76 and $90 with related parties as of March 31, 2021 and December 31, 2020, respectively)	6,420	5,421
Current portion of long term debt	7,694	7,673
Short term lease liabilities	1,271	1,234
Other current liabilities	1,985	3,054
Total current liabilities	36,491	39,803
Deferred revenue, net of current portion	776	577
Long term lease liabilities	21,552	21,891
Other non-current liabilities	2,378	2,649
Total liabilities	61,197	64,920
Stockholders' equity:
Common stock, $0.001 par value: Authorized-120,000,000 shares as of March 31, 2021 and December 31, 2020; issued and outstanding - 36,294,928 and 31,796,544 shares as of March 31, 2021 and December 31, 2020, respectively	36	32
Additional paid-in capital	728,128	451,433
Accumulated other comprehensive income	1,183	2,434
Accumulated deficit	(257,878)	(247,774)
Total stockholders' equity	471,469	206,125
Total liabilities and stockholders' equity	$ 532,666	$ 271,045

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Condensed Consolidated Balance Sheets
Accounts receivable, reserve for doubtful accounts	$ 342	$ 370
Accounts receivable, related parties	137	172
Accounts payable, related parties	6	14
Other accrued expenses, related parties	4	1,377
Deferred revenue, current, related parties	$ 76	$ 90
Common stock, par value	$ 0.001	$ 0.001
Common stock, authorized shares	120,000,000	120,000,000
Common stock, shares issued	36,294,928	31,796,544
Common stock, shares outstanding	36,294,928	31,796,544

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Total revenue	$ 27,209	$ 15,727
Costs of goods sold:
Total costs of goods sold and services	10,860	8,914
Gross profit	16,349	6,813
Operating expenses:
Research and development (including related party activity of $8 and $0 for the three months ended March 31, 2021 and 2020, respectively)	6,683	4,268
Selling, general, and administrative (including related party activity of $14 and $0 for the three months ended March 31, 2021 and 2020, respectively)	19,455	14,273
Total operating expenses	26,138	18,541
Loss from operations	(9,789)	(11,728)
Interest income (expense), net	(163)	161
Other expense, net	(194)	(167)
Loss before income taxes	(10,146)	(11,734)
Income tax benefit	42	124
Net loss	$ (10,104)	$ (11,610)
Net loss per share, basic and diluted	$ (0.29)	$ (0.41)
Weighted-average common shares outstanding, basic and diluted	34,434,931	28,179,132
Product revenue
Total revenue	$ 18,248	$ 9,833
Costs of goods sold:
Total costs of goods sold and services	7,480	6,186
Service and other revenue
Total revenue	6,409	5,762
Costs of goods sold:
Total costs of goods sold and services	3,380	2,728
Collaboration and license revenue
Total revenue	261	$ 132
Grant revenue
Total revenue	$ 2,291

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related party activity research and development expenses	$ 8	$ 0
Related party activity in selling, general and administrative expenses	14	0
Product revenue
Related party revenue	92	120
Cost of revenue, related party activity	570	63
Service and other revenue
Related party revenue	24	24
Cost of revenue, related party activity	$ 17	$ 0

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (10,104)	$ (11,610)
Other comprehensive loss:
Cumulative translation adjustment	(1,251)	(1,047)
Total other comprehensive loss	(1,251)	(1,047)
Comprehensive loss	$ (11,355)	$ (12,657)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net loss	$ (10,104)	$ (11,610)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,151	1,046
Inventory step-up amortization	164	438
Credit loss expense on accounts receivable	20
Reduction in the carrying amounts of right-of-use assets	128
Stock-based compensation expense	3,386	2,109
Non-cash interest expense	22	22
Loss on disposal of fixed assets		69
Changes in operating assets and liabilities:
Accounts receivable	2,227	(1,174)
Prepaid expenses and other assets	(1,744)	(495)
Inventory	(2,327)	(1,398)
Other non-current assets	(16)	32
Accounts payable	(2,109)	(1,145)
Accrued compensation and benefits, other accrued expenses and other current liabilities	(5,598)	(1,710)
Contract acquisition costs	(72)	(110)
Operating lease liabilities	(307)	253
Other non-current liabilities	(107)	(177)
Deferred revenue	1,197	671
Net cash used in operating activities	(14,089)	(13,179)
Investing activities
Purchases of property and equipment	(79)	(426)
Proceeds from RADx grant on assets purchased	2,514
Net cash provided by (used in) investing activities	2,435	(426)
Financing activities
Proceeds from stock options exercised	3,076	496
Proceeds from ESPP purchase	519	440
Payments on notes payable		(75)
Net cash provided by financing activities	273,313	861
Net increase (decrease) in cash and cash equivalents	261,659	(12,744)
Effect of foreign currency exchange rate on cash	(171)	(78)
Cash, restricted cash, and cash equivalents at beginning of period	182,584	110,181
Cash, restricted cash, and cash equivalents at end of period	444,072	97,359
Supplemental cash flow information
Cash paid for interest	154	155
Purchases of property and equipment included in accounts payable	3,341	102
Reconciliation of cash, cash equivalents, and restricted cash:
Total cash, cash equivalents, and restricted cash	444,072	$ 97,359
Underwritten public offering
Financing activities
Sale of common stock in at-the-market offering, net	$ 269,718

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common stockUnderwritten public offering	Common stock	Additional paid-in capitalUnderwritten public offering	Additional paid-in capital	Accumulated other comprehensive income (loss) [Member]	Accumulated deficit	Underwritten public offering	Total
Beginning Balance at Dec. 31, 2019		$ 28		$ 345,027	$ (153)	$ (216,244)		$ 128,658
Beginning balance (in shares) at Dec. 31, 2019		28,112,201
Increase (Decrease) in Stockholders' Equity
Exercise of common stock option and warrants and vesting of restricted stock				496				496
Exercise of common stock option and warrants and vesting of restricted stock (in shares)		108,548
Stock-based compensation expense				2,109				2,109
Employee stock purchase plan				440				440
Employee stock purchase plan (in shares)		22,693
Cumulative translation adjustment					(1,047)			(1,047)
Net loss						(11,610)		(11,610)
Ending Balance at Mar. 31, 2020		$ 28		348,072	(1,200)	(227,854)		119,046
Ending Balance (in shares) at Mar. 31, 2020		28,243,442
Increase (Decrease) in Stockholders' Equity
Accumulated other comprehensive income								2,434
Beginning Balance at Dec. 31, 2020		$ 32		451,433	2,434	(247,774)		206,125
Beginning balance (in shares) at Dec. 31, 2020		31,796,544
Increase (Decrease) in Stockholders' Equity
Exercise of common stock option and warrants and vesting of restricted stock				3,076				3,076
Exercise of common stock option and warrants and vesting of restricted stock (in shares)		374,017
Sale of common stock	$ 4		$ 269,714				$ 269,718
Sale of common stock (in shares)	4,107,142
Stock-based compensation expense				3,386				3,386
Employee stock purchase plan				519				519
Employee stock purchase plan (in shares)		17,225
Cumulative translation adjustment					(1,251)			(1,251)
Net loss						(10,104)		(10,104)
Ending Balance at Mar. 31, 2021		$ 36		$ 728,128	$ 1,183	$ (257,878)		471,469
Ending Balance (in shares) at Mar. 31, 2021		36,294,928
Increase (Decrease) in Stockholders' Equity
Accumulated other comprehensive income								$ 1,183

Organization and operations

Organization and operations	3 Months Ended
	Mar. 31, 2021
Organization and operations
Organization and operations	Quanterix Corporation Notes to condensed consolidated financial statements (Unaudited) ​ 1. Organization and operations ​ Quanterix Corporation (Nasdaq: QTRX) (the Company) is a life sciences company that has developed next generation, ultra-sensitive digital immunoassay platforms that advance precision health for life sciences research and diagnostics. The Company's platforms are based on its proprietary digital "Simoa" detection technology. The Company's Simoa bead-based and planar array platforms enable customers to reliably detect protein biomarkers in extremely low concentrations in blood, serum and other fluids that, in many cases, are undetectable using conventional, analog immunoassay technologies, and also allow researchers to define and validate the function of novel protein biomarkers that are only present in very low concentrations and have been discovered using technologies such as mass spectrometry. These capabilities provide the Company's customers with insight into the role of protein biomarkers in human health that has not been possible with other existing technologies and enable researchers to unlock unique insights into the continuum between health and disease. The Company is currently focusing on protein detection, which it believes is an area of significant unmet need and where it has significant competitive advantages. However, in addition to enabling new applications and insights in protein analysis, the Company’s Simoa platforms have also demonstrated applicability across other testing applications, including detection of nucleic acids and small molecules. ​ The Company launched its first immunoassay platform, the Simoa HD-1, in 2014. The HD-1 is a fully automated immunoassay bead-based platform with multiplexing and custom assay capability, and related assay test kits and consumable materials. The Company launched a second bead-based immunoassay platform (SR-X) in the fourth quarter of 2017 with a more compact footprint than the Simoa HD-1 and less automation designed for lower volume requirements while still allowing multiplexing and custom assay capability. The Company initiated an early-access program for its third instrument (SP-X) on the new Simoa planar array platform in January 2019, with the full commercial launch commencing in April 2019. In July 2019, the Company launched the Simoa HD-X, an upgraded version of the Simoa HD-1 which replaces the HD-1. The HD-X has been designed to deliver significant productivity and operational efficiency improvements, as well as greater user flexibility. The Company began shipping and installing HD-X instruments at customer locations in the third quarter of 2019. The Company also performs research services on behalf of customers to apply the Simoa technology to specific customer needs. The Company's customers are primarily in the research use only market, which includes academic and governmental research institutions, the research and development laboratories of pharmaceutical manufacturers, contract research organizations, and specialty research laboratories. ​ The Company acquired Aushon Biosystems, Inc. (Aushon) in January 2018. With the acquisition of Aushon, the Company acquired a CLIA certified laboratory, as well as Aushon's proprietary sensitive planar array detection technology. Leveraging its proprietary sophisticated Simoa image analysis and data analysis algorithms, the Company further refined this planar array technology to develop the SP-X instrument to provide the same Simoa sensitivity found in its bead-based platform. ​ The Company completed the acquisition of UmanDiagnostics AB (Uman), a Swedish company located in Umea, Sweden, in August 2019. Uman supplies neurofilament light (Nf-L) antibodies and ELISA kits, which are widely recognized by researchers and biopharmaceutical and diagnostics companies world-wide as the premier solution for the detection of Nf-L to advance the development of therapeutics and diagnostics for neurodegenerative conditions. With the acquisition of Uman, the Company has secured a long-term source of supply for a critical technology. ​ Underwritten public offerings ​ On August 6, 2020, the Company entered into an underwriting agreement with Leerink and Cowen, as representatives of the several underwriters, relating to an underwritten public offering of approximately 3.0 million shares of the Company’s common stock, par value $0.001 per share. The underwritten public offering resulted in gross proceeds of $97.6 million. The Company incurred $6.2 million in issuance costs associated with the underwritten public offering, resulting in net proceeds to the Company of $91.4 million. On February 3, 2021, the Company entered into an underwriting agreement with Goldman Sachs & Co. LLC, SVB Leerink LLC, and Cowen, as representatives of the several underwriters, relating to an underwritten public offering of approximately 4.1 million shares of the Company’s common stock, par value $0.001 per share. The underwritten public offering resulted in gross proceeds of $287.5 million. The Company incurred $17.8 million in issuance costs associated with the underwritten public offering, resulting in net proceeds to the Company of $269.7 million. ​ Basis of presentation ​ The interim condensed consolidated financial statements are unaudited. The unaudited condensed consolidated financial statements reflect, in the opinion of the Company’s management, all adjustments, consisting of only normal recurring adjustments, necessary for a fair presentation of financial position, results of operations, comprehensive loss and cash flows for each period presented in accordance with United States generally accepted accounting principles (U.S. GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. These interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 filed with the Securities and Exchange Commission on March 5, 2021 (the 2020 Annual Report on Form 10-K). The consolidated financial information as of December 31, 2020 has been derived from the audited 2020 consolidated financial statements included in the 2020 Annual Report on Form 10-K.

Significant accounting policies

Significant accounting policies	3 Months Ended
	Mar. 31, 2021
Significant accounting policies
Significant accounting policies	2. Significant accounting policies Principles of consolidation The condensed consolidated financial statements have been prepared in accordance with U.S. GAAP and include the accounts of Quanterix Corporation and its wholly-owned subsidiaries. All material intercompany transactions and balances have been eliminated in consolidation. Use of estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. In making those estimates and assumptions, the Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. The Company’s significant estimates included in the preparation of the consolidated financial statements are related to revenue recognition, fair value of assets acquired and liabilities assumed in acquisitions, valuation allowances recorded against deferred tax assets, and valuation of inventory. Actual results could differ from those estimates. Foreign currency Income taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company's consolidated financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on differences between the consolidated financial statement carrying amounts and the tax bases of the assets and liabilities using the enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance against deferred tax assets is recorded if, based on the weight of the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company accounts for uncertain tax positions in accordance with the provisions of Accounting Standards Codification (ASC) 740, Income Taxes ​ Business combinations Under the acquisition method of accounting, the Company generally recognizes the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values on the date of acquisition. The fair values assigned, defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between willing market participants, are based on estimates and assumptions determined by management. The excess consideration over the aggregate value of tangible and intangible assets, net of liabilities assumed, is recorded as goodwill. These valuations require significant estimates and assumptions, especially with respect to intangible assets. The Company typically uses the discounted cash flow method to value acquired intangible assets. This method requires significant management judgment to forecast future operating results and establish residual growth rates and discount factors. The estimates used to value and amortize intangible assets are consistent with the plans and estimates that are used to manage the business and are based on available historical information and industry estimates and averages. If the subsequent actual results and updated projections of the underlying business activity change compared with the assumptions and projections used to develop these values, the Company could experience impairment charges. In addition, the Company has estimated the economic lives of certain acquired assets and these lives are used to calculate depreciation and amortization expense. If estimates of the economic lives change, depreciation or amortization expenses could be accelerated or slowed. Restricted cash Restricted cash primarily represents collateral for a letter of credit issued as security for the lease for the Company’s headquarters in Billerica, Massachusetts, and to secure the Company’s corporate credit card program. The restricted cash is long term in nature as the Company will not have access to the funds until more than one year from March 31, 2021. Recent accounting pronouncements The Company is considered to be an “emerging growth company” (EGC) as defined in the Jumpstart Our Business Startups Act of 2012, as amended (JOBS Act). The JOBS Act provides that an EGC can take advantage of an extended transition period for complying with new or revised accounting standards. Thus, an EGC can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company may remain an EGC until the last day of the fiscal year in which the fifth anniversary of the closing of the initial public offering occurs, although if the market value the Company’s common stock that is held by non-affiliates exceeds $700 million as of any June 30 before that time or if the Company has annual gross revenues of $1.07 billion or more in any fiscal year, the Company would cease to be an EGC as of December 31 of the applicable year. The Company also would cease to be an EGC if it issues more than $1 billion of non-convertible debt over a three-year period. The Company has elected to avail itself of this extended transition period and, as a result, the Company will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for other public companies so long as the Company remains an EGC. Recently Adopted In June 2016, the Financial Accounting Standards Board (FASB) established Topic 326 , Financial Instruments — Credit Losses: Measurement of Credit Losses on Financial Instruments looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables and available-for-sale debt securities. The Company early adopted ASU 2016-13 on January 1, 2021 using the modified retrospective approach. The Company’s consolidated financial statements for prior-year periods have not been revised and are reflective of the credit loss requirements which were in effect for that period. The adoption of ASU 2016-13 did not have a material impact on the Company’s consolidated financial statements. ​ In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . This ASU addresses the accounting for implementation, setup and other upfront costs paid by a customer in a cloud computing or hosting arrangement. The guidance aligns the accounting treatment of these costs incurred in a hosting arrangement treated as a service contract with the requirements for capitalization and amortization costs to develop or obtain internal-use software. The Company adopted ASU 2018-15 on January 1, 2021 using the prospective method. The Adoption of ASU 2018-15 did not have a material impact on the Company’s consolidated financial statements. ​ In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes Income Taxes There have been no other material changes to the significant accounting policies and recent accounting pronouncements previously disclosed in the 2020 Annual Report on Form 10-K.

Revenue recognition

Revenue recognition	3 Months Ended
	Mar. 31, 2021
Revenue recognition
Revenue recognition	3. Revenue recognition The Company recognizes revenue when a customer obtains control of a promised good or service. The amount of revenue recognized reflects consideration that the Company expects to be entitled to receive in exchange for these goods and services, incentives and taxes collected from customers, that are subsequently remitted to governmental authorities. Customers The Company’s customers primarily consist of entities engaged in the life sciences research market that pursue the discovery and development of new drugs for a variety of neurologic, cardiovascular, oncologic and other protein biomarkers associated with diseases. The Company’s customer base includes several of the largest biopharmaceutical companies, academic research organizations and distributors who serve certain geographic markets. Product revenue The Company’s products are composed of analyzer instruments, assay kits and other consumables such as reagents. Products are sold directly to biopharmaceutical and academic research organizations or are sold through distributors in EMEA and Asia Pacific regions. The sales of instruments are generally accompanied by an initial year of implied service-type warranties and may be bundled with assays and other consumables and may also include other items such as training and installation of the instrument and/or an extended service warranty. Revenues from the sale of products are recognized at a point in time when the Company transfers control of the product to the customer, which is upon installation for instruments sold to direct customers, and based upon shipping terms for assay kits and other consumables. Revenue for instruments sold to distributors is generally recognized based upon shipping terms (either upon shipment or delivery). ​ Service and other revenue Service revenues are composed of contract research services, initial implied one-year service-type warranties, extended services contracts and other services such as training. Contract research services are provided through the Company’s Accelerator Laboratory and generally consist of fixed fee contracts. Revenues from contract research services are recognized at a point in time when the Company completes and delivers its research report on each individually completed study, or over time if the contractual provisions allow for the collection of transaction consideration for costs incurred plus a reasonable margin through the period of performance of the services. Revenues from service-type warranties are recognized ratably over the contract service period. Revenues from other services are immaterial. Collaboration and license revenue The Company may enter into agreements to license the intellectual property and know-how associated with its instruments and certain antibodies in exchange for license fees and future royalties (as described below). The license agreements provide the licensee with a right to use the intellectual property with the license fee revenues recognized at a point in time as the underlying license is considered functional intellectual property. Payment terms The Company’s payment terms vary by the type and location of the customer and the products or services offered. Payment from customers is generally required in a term ranging from 30 Disaggregated revenue When disaggregating revenue, the Company considered all of the economic factors that may affect its revenues. The following tables disaggregate the Company's revenue from contracts with customers by revenue type (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2021 (in thousands) NA EMEA Asia Pacific Total Product revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments $ 3,756 ​ $ 2,833 ​ $ 372 ​ $ 6,961 Consumable and other products ​ 6,911 ​ ​ 3,493 ​ ​ 883 ​ ​ 11,287 Totals $ 10,667 $ 6,326 $ 1,255 $ 18,248 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties $ 971 ​ $ 438 ​ $ 62 ​ $ 1,471 Research services ​ 3,558 ​ ​ 728 ​ ​ 12 ​ 4,298 Other services ​ 456 ​ ​ 184 ​ ​ — ​ ​ 640 Totals ​ $ 4,985 ​ $ 1,350 ​ $ 74 ​ $ 6,409 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 187 ​ $ 74 ​ $ — ​ $ 261 Totals $ 187 $ 74 $ — $ 261 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2020 (in thousands) NA EMEA Asia Pacific Total Product revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments $ 1,753 $ 726 $ 1,209 $ 3,688 Consumable and other products ​ 2,924 ​ 2,704 ​ 517 ​ 6,145 Totals $ 4,677 $ 3,430 $ 1,726 $ 9,833 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties $ 748 $ 379 $ 52 $ 1,179 Research services ​ 3,667 ​ 82 ​ 538 ​ 4,287 Other services ​ 231 ​ 60 ​ 5 ​ 296 Totals ​ $ 4,646 ​ $ 521 ​ $ 595 ​ $ 5,762 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 122 ​ $ 10 ​ $ — ​ $ 132 Totals $ 122 $ 10 $ — $ 132 ​ The Company’s contracts with customers may include promises to transfer multiple products and services to a customer. The Company combines any performance obligations that are immaterial with one or more other performance obligations that are material to the contract. For arrangements with multiple performance obligations, the Company allocates the contract transaction price, including discounts, to each performance obligation based on its relative standalone selling price. Judgment is required to determine the standalone selling price for each distinct performance obligation. The Company determines standalone selling prices based on prices charged to customers in observable transactions, and uses a range of amounts to estimate standalone selling prices for each performance obligation. The Company may have more than one range of standalone selling price for certain products and services based on the pricing for different customer classes. Variable consideration in the Company’s contracts primarily relates to (i) sales- and usage-based royalties related to the license of intellectual property in collaboration and license contracts and (ii) certain non-fixed fee research services contracts. ASC 606 provides for an exception to estimating the variable consideration for sales- and usage-based royalties related to the license of intellectual property, such that the sales- and usage-based royalty will be recognized in the period the underlying transaction occurs. The Company recognizes revenue from sales- and usage-based royalty revenue at the later of when the sale or usage occurs and the satisfaction or partial satisfaction of the performance obligation to which the royalty has been allocated. The aggregate amount of transaction price that is allocated to performance obligations that have not yet been satisfied or are partially satisfied as of March 31, 2021 and 2020 is $7.2 million and $5.8 million, respectively. As of March 31, 2021, of the performance obligations not yet satisfied or partially satisfied, $6.4 million is expected to be recognized as revenue in the next 12 months, with the remainder amounts Changes in deferred revenue from contracts with customers were as follows (in thousands): ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 Balance at December 31, 2020 $ 5,998 Deferral of revenue ​ 2,669 Recognition of deferred revenue ​ (1,471) Balance at March 31, 2021 $ 7,196 ​ Costs to obtain a contract The Company’s sales commissions are generally based on revenues of the Company. The Company has determined that certain commissions paid under its sales incentive programs meet the requirements to be capitalized as they are incremental and would not have occurred absent a customer contract. The change in the balance of costs to obtain a contract are as follows (in thousands): ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 Balance at December 31, 2020 $ 248 Deferral of costs to obtain a contract ​ 88 Recognition of costs to obtain a contract ​ (160) Balance at March 31, 2021 $ 176 ​ The Company has classified the balance of capitalized costs to obtain a contract as a component of prepaid expenses and other current assets and classifies the expense as a component of cost of goods sold and selling, general, and administrative expense over the estimated life of the contract. The Company considers potential impairment in these amounts each period. ASC 606 provides entities with certain practical expedients and accounting policy elections to minimize the cost and burden of adoption. The Company does not disclose the value of unsatisfied performance obligations for (i) contracts with original expected length of one year or less and (ii) contracts for which revenue is recognized at the amount to which the Company has the right to invoice for services performed. The Company will exclude from its transaction price any amounts collected from customers related to sales and other similar taxes. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. The Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. None of the Company’s contracts contained a significant financing component as of March 31, 2021 and 2020, respectively. The Company has elected to account for the shipping and handling as an activity to fulfill the promise to transfer the product, and therefore will not evaluate whether shipping and handling activities are promised services to its customers. Grant revenue ​ The Company recognizes grant revenue as it performs services under the arrangement when the funding is committed. Revenues and related research and development expenses are presented gross in the consolidated statements of operations as the Company has determined it is the primary obligor under the arrangement relative to the research and development services. ​ Accounting for grants does not fall under ASC 606, as the grantor will not benefit directly from the Company’s expansion or product development. As there is no authoritative guidance under U.S. GAAP on accounting for government assistance to for-profit business entities, the Company has accounted for grants by analogy to International Accounting Standards (IAS) 20, Accounting for Government Grants and Disclosure of Government Assistance ​ Grants to the Company contain both monetary amounts granted related to assets and monetary amounts granted related to income, which are grants other than those related to assets. The grants related to assets are for the expansion and increase of manufacturing capacity. The grants related to income are for additional research and development, as well as other non-asset related scale up costs. ​ Under IAS 20, grants related to assets shall be presented in the consolidated balance sheets either by recognizing the grant as deferred income (which is recognized in the consolidated statements of operations on a systematic basis over the useful life of the asset), or by deducting the grant in calculating the carrying amount of the asset (which is recognized in the consolidated statements of operations over the life of the depreciable asset as a reduced depreciation expense). Both methods are acceptable under IAS 20. The Company has elected to record grants related to assets as a deduction in calculating the carrying value of the asset. ​ Under IAS 20, grants related to income are presented as part of the consolidated statements of operations, either separately or under a general heading. Both methods are acceptable under IAS 20. The Company has elected to record grants related to income separately on the consolidated statements of operations as grant revenue. The related expenses are recorded within operating expenses. ​ On June 22, 2020, the Company entered into a workplan 1 award (WP1) with the National Institute of Health (NIH), under the Rapid Acceleration of Diagnostics (RADx) program to assess the feasibility of a novel SARS-CoV-2 antigen detection test using the Company’s Simoa technology. WP1 was complete as of December 31, 2020. ​ On September 29, 2020, the Company entered into a workplan 2 award (WP2) with the NIH under its RADx program. WP2, which has a total award value of $18.2 million, accelerates the continued development, scale-up, and deployment of the novel SARS-CoV-2 antigen detection test using the Company’s Simoa technology. The contract provides funding to expand assay kit manufacturing capacity and commercial deployment readiness. Release of the $18.2 million of funding under WP2 is based on the achievement of certain milestones, and there is no assurance that the Company can meet all the milestones on a timely basis, if at all. If the Company does not meet all of the milestones, it will not be able access the full $18.2 million in funding under the contract. During the three months ended March 31, 2021 the Company recognized $2.3 million in grant revenue and incurred $1.8 million in research and development expense related to WP2. ​ The following table summarizes the activity under WP2 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ December 31, 2020 ​ ​ ​ ​ ​ ​ Total grant revenue from research and development activities $ 6,653 ​ $ 4,362 Total proceeds used for assets ​ 4,622 ​ ​ 826 Total deferred proceeds for assets ​ 1,159 ​ ​ 2,478 Total deferred grant revenue ​ 500 ​ ​ 304 Total recognized $ 12,934 ​ $ 7,970 ​ ​ ​ ​ ​ ​ Total recognized $ 12,934 ​ $ 7,970 Total amount accrued ​ (2,961) ​ ​ (2,968) Total cash received $ 9,973 ​ $ 5,002 ​ ​ ​ ​ ​ ​ Total proceeds received $ 9,973 ​ $ 5,002 Total proceeds reasonably assured ​ 8,227 ​ ​ 13,198 Total WP2 grant amount $ 18,200 ​ $ 18,200 ​

Net loss per share

Net loss per share	3 Months Ended
	Mar. 31, 2021
Net loss per share
Net loss per share	4. Net loss per share Basic net loss per common share is calculated by dividing the net loss by the weighted-average number of common shares outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common shares and potentially dilutive securities outstanding for the period determined using the treasury-stock and if-converted methods. For purposes of the diluted net loss per share calculation, unvested restricted common stock, restricted stock units, stock options, and warrants are considered to be potentially dilutive securities, but are excluded from the calculation of diluted net loss per share because their effect would be anti-dilutive and therefore basic and diluted net loss per share were the same for all periods presented. The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to do so would be anti-dilutive (in common stock equivalent shares): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ 2021 2020 ​ Unvested restricted common stock and restricted stock units 563,810 561,786 ​ Outstanding stock options 2,428,268 2,840,525 Outstanding common stock warrants — 10,000 Total 2,992,078 3,412,311 ​ As of March 31, 2021 and 2020, the Company had an obligation to issue warrants to purchase an additional 93,341 shares of common stock to a vendor if a contract is terminated prior to a minimum purchase commitment being met. No amounts are presented in the table above for this obligation to issue a warrant as the issuance of the warrant is not considered probable.

Fair value of financial instrum

Fair value of financial instruments	3 Months Ended
	Mar. 31, 2021
Fair value of financial instruments
Fair value of financial instruments	5. Fair value of financial instruments ASC Topic 820, Fair Value Measurement ASC 820 identifies fair value as the exchange price, or exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tier fair value hierarchy that distinguishes between the following: Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; Level 2 inputs are inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly; and Level 3 inputs are unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Fair value measurements as of March 31, 2021 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs Description Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 162,059 $ 162,059 ​ $ — $ — ​ ​ $ 162,059 ​ $ 162,059 ​ $ — ​ $ — ​ Fair value measurements as of December 31, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs Description Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 162,048 $ 162,048 ​ $ — $ — ​ $ 162,048 $ 162,048 ​ $ — $ — ​

Inventory

Inventory	3 Months Ended
	Mar. 31, 2021
Inventory
Inventory	6. Inventory Inventory consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2021 2020 Raw materials ​ $ 5,608 ​ $ 5,265 ​ Work in process ​ 4,012 ​ 3,306 ​ Finished goods ​ 7,424 ​ 6,285 ​ Total ​ $ 17,044 ​ $ 14,856 ​ ​ Inventory comprises commercial instruments, assays, and the materials required to manufacture limited instruments and assays.

Allowance for Credit Losses

Allowance for Credit Losses	3 Months Ended
	Mar. 31, 2021
Allowance for Credit Loss
Allowance for Credit Loss	7. Allowance for Credit Losses The Company is exposed to credit losses primarily through sales of products and services. The Company’s expected loss allowance methodology for accounts receivable is developed using historical collection experience, current and future economic and market conditions, and a review of the current status of customers’ trade accounts receivable. Due to the short-term nature of such receivables, the estimated accounts receivable that may not be collected is based on aging of the accounts receivable balances. Customers are assessed for credit worthiness upfront through a credit review, which includes assessment based on the Company’s analysis of their financial statements when a credit rating is not available. The Company evaluates contract terms and conditions, country, and political risk, and may require prepayment to mitigate risk of loss. Specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default. The Company monitors changes to the receivables balance on a timely basis, and balances are written off as they are determined to be uncollectable after all collection efforts have been exhausted. As of March 31, 2021, the Company’s accounts receivable balance was $14.9 million, net of of allowance for credit losses. The following table provides a roll-forward of the allowance for credit losses for the three months ended March 31, 2021 that is deducted from the amortized cost basis of accounts receivable to present the net amount expected to be collected (in thousands): ​ ​ ​ ​ ​ Balance at January 1, 2021 ​ $ 370 Credit loss expense ​ ​ 20 Write-offs charged against allowances ​ ​ (48) Balance at March 31, 2021 ​ $ 342 ​

Other accrued expenses and othe

Other accrued expenses and other non-current liabilities	3 Months Ended
	Mar. 31, 2021
Other accrued expenses and other non-current liabilities
Other accrued expenses	​ 8. Other accrued expenses and other non-current liabilities Other accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2021 2020 Accrued inventory purchases ​ $ 878 ​ $ 527 Accrued property and equipment purchases ​ ​ 1,532 ​ ​ 670 Accrued royalties ​ 1,124 ​ 1,845 Accrued professional services ​ 863 ​ 797 Accrued development costs ​ 241 ​ 323 Accrued other ​ 965 ​ 683 Total accrued expenses ​ $ 5,603 ​ $ 4,845 ​ Other non-current liabilities consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2021 2020 Deferred tax liabilities ​ $ 2,378 ​ $ 2,649 Total other non-current liabilities ​ $ 2,378 ​ $ 2,649 ​

Warrants, stock-based compensat

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units	3 Months Ended
	Mar. 31, 2021
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units	9. Warrants, stock-based compensation, stock options, restricted stock and restricted stock units Warrants On January 20, 2021, 10,000 warrants were exercised by a holder on a net, non-cash, basis. Per terms of the warrant agreement, the Company issued 7,347 shares of common stock with a value equal to the holder’s gain. The Company had no warrants outstanding as of March 31, 2021. Stock-based compensation Stock-based compensation expense for all stock awards consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ ​ 2021 2020 ​ Cost of product revenue ​ $ 90 ​ $ 36 ​ Cost of service and other revenue ​ 110 ​ 68 ​ Research and development ​ 399 ​ 242 ​ Selling, general, and administrative ​ 2,787 ​ 1,763 ​ Total ​ $ 3,386 ​ $ 2,109 ​ ​ In June 2007, the Company adopted the 2007 Stock Option and Grant Plan (the 2007 Plan), under which it could grant incentive stock options, non-qualified options, restricted stock, and stock grants. In connection with the completion of the IPO, the Company terminated the 2007 Plan. As of March 31, 2021, 736,958 shares were outstanding, and no shares were available for future grant under the 2007 Plan. In December 2017, the Company adopted the 2017 Employee, Director and Consultant Equity Incentive Plan (the 2017 Plan), under which it may grant incentive stock options, non-qualified stock options, restricted stock, and other stock-based awards. As of December 31, 2017, the 2017 Plan allowed for the issuance of up to 1,042,314 shares of common stock plus up to 2,490,290 shares of common stock represented by awards granted under the 2007 Plan that are forfeited, expire, or are cancelled without delivery of shares or which result in the forfeiture of shares of common stock back to the Company on or after the date the 2017 Plan became effective. As of March 31, 2021, there were shares available for grant under the 2017 Plan of 1,637,976. In addition, the 2017 Plan contains an "evergreen" provision, which allows for an annual increase in the number of shares of common stock available for issuance under the 2017 Plan on the first day of each fiscal year during the period beginning in fiscal year 2019 and ending in fiscal year 2027. The annual increase in the number of shares shall be equal to the lowest of: 4% of the number of shares of common stock outstanding as of such date; and an amount determined by the Company’s Board of Directors or Compensation Committee. On January 1, 2021, the number of shares of common stock available for issuance under the 2017 plan was automatically increased by 1,273,501 shares. In December 2017, the Company adopted the 2017 Employee Stock Purchase Plan (the 2017 ESPP). As December 31, 2020, the 2017 ESPP allowed for the issuance of up to 848,269 shares of common stock. As of March 31, 2021, 1,149,407 shares were available for grant under the 2017 ESPP. In addition, the 2017 ESPP contains an "evergreen" provision, which allows for an increase on the first day of each fiscal year beginning with fiscal year 2018. The increase in the number of shares shall be equal to the lowest of: 1% of the number of shares of common stock outstanding on the last day of the immediately preceding fiscal year or an amount determined by the Company’s Board of Directors or Compensation Committee. The number of shares available for grant under the 2017 ESPP increased by 318,375 shares on January 1, 2021 due to this provision. The 2017 ESPP provides for six-month option periods commencing on March 1 and ending August 31 and commencing September 1 and ending February 28 of each calendar year. The first offering under the 2017 ESPP began on September 1, 2018. Stock options Under the 2007 Plan and the 2017 Plan, stock options may not be granted with exercise prices of less than fair market value on the date of the grant. Options generally vest ratably over a four-year period with 25% vesting on the first anniversary and the remaining 75% vesting ratably on a monthly basis over the remaining three years. These options expire ten years after the grant date. Activity under the 2007 Plan and the 2017 Plan was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ Remaining contractual ​ Aggregate intrinsic value ​ Options exercise price life (in years) (in thousands) Outstanding at December 31, 2020 2,494,045 $ 17.73 ​ 7.27 ​ $ 71,760 Granted 241,713 ​ $ 69.97 ​ ​ ​ ​ ​ Exercised (281,324) ​ $ 10.93 ​ ​ ​ ​ ​ Cancelled (26,166) ​ $ 35.98 ​ ​ ​ ​ ​ Outstanding at March 31, 2021 2,428,268 ​ $ 23.52 ​ 7.37 ​ $ 88,387 Vested and expected to vest at March 31, 2021 2,428,268 ​ $ 23.52 ​ 7.37 ​ $ 88,387 Exercisable at March 31, 2021 ​ 1,428,652 ​ $ 14.31 ​ 6.43 ​ $ 63,050 ​ Using the Black-Scholes option pricing model, the weighted-average fair value of options granted to employees and directors during the three months ended March 31, 2021 and 2020 was $32.83 and $11.82 per share, respectively. The expense related to awards granted to employees was $1.5 million and $1.1 million for the three months ended March 31, 2021 and 2020, respectively. The intrinsic value of stock options exercised was $16.2 million and $1.1 million for the three months ended March 31, 2021 and 2020, respectively. Activity related to non-employee awards was not material to the three months ended March 31, 2021 and 2020. Restricted stock Restricted common stock awards represent shares of common stock issued to employees subject to forfeiture if the vesting conditions are not satisfied. Vesting occurs periodically at specified time intervals and specified percentages. In January 2015, the Company issued 781,060 shares of restricted common stock to an executive of the Company under the 2007 Plan. The majority of these shares were issued subject to a four-year vesting schedule with 25% vesting on the first anniversary and the remaining vesting 75% ratably on a monthly basis over the remaining three years, while another portion was issued subject to performance based vesting. The vesting of performance based awards is dependent upon achievement of specified financial targets of the Company. The majority of the performance criteria were achieved during the years ended December 31, 2016 and 2015 and the remaining unvested awards with performance conditions are not material. No restricted common stock awards were granted or vested during the three months ended March 31, 2021. As of March 31, 2021, the Company had 39,806 shares of unvested restricted common stock with a weighted average grant date fair value of $3.12 per share. Restricted stock units Restricted stock units (RSUs) represent the right to receive shares of common stock upon meeting specified vesting requirements. In the three months ended March 31, 2021, the Company issued 140,814 RSUs to employees of the Company under the 2017 Plan. Under the terms of the agreements, 126,007 of the RSUs issued are subject to a four-year vesting schedule with 25% vesting on the first anniversary of the grant date and the remaining vesting 75% ratably on a monthly basis over the remaining three years; 13,620 of the RSUs vest on December 31, 2021; and 1,187 vested immediately upon grant. A summary of RSU activity is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ ​ ​ ​ grant date ​ ​ ​ ​ fair value ​ Shares per share Unvested RSUs as of December 31, 2020 478,581 $ 28.08 Granted 140,814 ​ $ 71.28 Vested (85,346) ​ $ 24.50 Cancelled (10,045) ​ $ 41.14 Unvested RSUs as of March 31, 2021 524,004 ​ $ 40.02 ​ The expense related to awards granted to employees and directors was $1.7 million and $0.9 million for the three months ended March 31, 2021 and 2020, respectively. As of March 31, 2021, there was $19.9 million of total unrecognized compensation cost related to unvested RSUs, which is expected to be recognized over the remaining weighted-average vesting period of 3.1 years.

Leases

Leases	3 Months Ended
	Mar. 31, 2021
Leases
Leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10. Leases ​ The Company is a lessee under leases of offices, lab spaces, and certain office equipment. Some of the Company’s leases include options to extend the lease, and these options are included in the lease term to the extent they are reasonably certain to be exercised. ​ Summary of all lease costs recognized under ASC 842 ​ The following table contains a summary of the lease costs recognized under ASC 842 and other information pertaining to the Company’s operating leases for the three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ Operating leases (in thousands) ​ 2021 ​ 2020 ​ Lease Costs (1) ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 671 ​ $ 660 ​ Total lease cost ​ $ 671 ​ $ 660 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other information ​ ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 846 ​ $ 407 ​ Weighted average remaining lease term (years) ​ ​ 9.6 years ​ 10.3 years Weighted average discount rate ​ ​ 9.73% ​ ​ 9.73% ​ ​ ​ (1) Short-term lease costs and variable lease costs incurred by the Company for the three months ended March 31, 2021 and 2020 were immaterial, respectively. ​ ​ ​ ​

Commitments and contingencies

Commitments and contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and contingencies
Commitments and contingencies	11. Commitments and contingencies Tufts University In June 2007, the Company entered into a license agreement (the License Agreement) for certain intellectual property with Tufts University (Tufts). Tufts is a related party to the Company due to Tufts’ equity ownership in the Company and because a member of the Company’s Board of Directors was affiliated with Tufts. The License Agreement, which was subsequently amended, is exclusive and sublicensable, and will continue in effect on a country-by-country basis as long as there is a valid claim of a licensed patent in a country. The Company is committed to pay license and maintenance fees, prior to commercialization, in addition to low single digit royalties on direct sales and services and a royalty on sublicense income. During the three months ended March 31, 2021 and 2020, the Company recorded royalty expense of $0.5 million and $0.2 million, respectively, in cost of product revenue on the consolidated statements of operations. Supply agreement The Company’s supply agreement with STRATEC Biomedical requires the Company to purchase a minimum number of commercial units over a seven-year period ending in May 2021. If the Company were to fail to purchase a required number of commercial units, the Company would be obligated to pay termination costs plus a fee based on the shortfall of commercial units purchased compared to the required minimum amount. Based on the number of commercial instruments purchased as of March 31, 2021, the Company has satisfied its required minimum purchase amount per the supply agreement. Also, if the Company terminates the supply agreement under certain circumstances and has not purchased a required number of commercial units, it would be obligated to issue warrants to purchase 93,341 shares of common stock (the Supply Warrants) at $0.003214 per share. The Company believes that it will purchase sufficient units to meet the requirements of the minimum purchase commitment and, therefore, has not accrued for any of the potential cash consideration. The Supply Warrants are accounted for at fair value; however, the fair value of the Supply Warrants as of March 31, 2021 and December 31, 2020 was insignificant as there was a low probability of the warrants being issued. Legal contingencies The Company is subject to claims in the ordinary course of business; however, the Company is not currently a party to any pending or threatened litigation, the outcome of which would be expected to have a material adverse effect on its financial condition or the results of its operations. The Company accrues for contingent liabilities to the extent that the liability is probable and estimable.

Notes payable

Notes payable	3 Months Ended
	Mar. 31, 2021
Notes payable
Notes payable	12. Notes payable Loan agreement On April 14, 2014, the Company executed a loan agreement with a lender, as subsequently amended. As of March 31, 2021, there were no additional amounts available to borrow under the debt facility. The interest rate on this term loan is variable based on the greater of 8% or 8% plus the prime rate less 5.25%. Interest is paid monthly beginning the month following the borrowing date. At loan inception and in connection with the amendments, the Company issued the lender warrants to purchase shares of stock. The loan agreement also contains prepayment penalties and an end of term charge. Fees incurred upon execution of the agreements, and the fair value of warrants on the date of grant were accounted for as a reduction in the book value of debt and accreted through interest expense, using the effective interest rate method, over the term of the debt. Under the amended agreement, the Company is required to pay the loan principal in four equal installments starting July 1, 2021, with the final payment and end of term charge to be made on October 1, 2021. As of March 31, 2021, debt payment obligations due based on principal payments are as follows (in thousands): ​ ​ ​ ​ ​ 2021 ​ $ 7,688 Total ​ $ 7,688 ​ Non-cash interest expense related to debt discount amortization and accretion of end of term fees was $0.1 million or less for each of the three months ended March 31, 2021 and 2020.

Collaboration and license arran

Collaboration and license arrangements	3 Months Ended
	Mar. 31, 2021
Collaboration and license arrangements
Collaboration and license arrangements	13. Collaboration and license arrangements The Company has entered into certain licenses with other companies for use of the Company’s technology. These licenses have royalty components which the Company earns and recognizes as collaboration and license revenue throughout the year. The Company recognized revenue of $0.3 million for the three months ended March 31, 2021 and $0.1 million for the three months ended March 31, 2020 associated with these licenses. ​ As of March 31, 2021 and December 31, 2020, the Company had $0.5 million of deferred revenue related to ongoing negotiations with a diagnostics company. ​ Abbott Laboratories ​ On September 29, 2020, the Company entered into a Non-Exclusive License Agreement (the Abbott License Agreement) with Abbott Laboratories (Abbott). Pursuant to the terms of the Abbott License Agreement, the Company granted Abbott a non-exclusive, worldwide, royalty-bearing license, without the right to sublicense, under the Company’s bead-based single molecule detection patents (Licensed Patents) in the field of in vitro The Abbott License Agreement includes customary representations and warranties, covenants and indemnification obligations for a transaction of this nature. The Abbot License Agreement became effective upon signing and will continue until expiration of the last-to-expire Licensed Patent, or the agreement is earlier terminated. Under the terms of the Abbott License Agreement, the Company and Abbott each have the right to terminate the agreement for uncured material breach by, or insolvency of, the other party. Abbott may also terminate the Abbott License Agreement at any time without cause upon 60 days’ notice. ​ During the three months ended March 31, 2021, the Company recognized no revenue under the Abbott License Agreement. ​

Employee benefit plans

Employee benefit plans	3 Months Ended
	Mar. 31, 2021
Employee benefit plans
Employee benefit plans	14. Employee benefit plans ​ The Company sponsors a 401(k) savings plan for its employees. The Company may make discretionary contributions for each 401(k) plan year. During the three months ended March 31, 2021 and 2020, the Company made contributions of $0.2 million and $0.1 million, respectively. ​

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets
Goodwill and Intangible Assets	15. Goodwill and acquired intangible assets As of March 31, 2021, the carrying amount of goodwill was $9.9 million. The following is a rollforward of the Company’s goodwill balance (in thousands): ​ ​ ​ ​ ​ ​ Goodwill Balance as of December 31, 2020 ​ $ 10,460 Cumulative translation adjustment ​ ​ (527) Balance as of March 31, 2021 ​ $ 9,933 ​ Acquired intangible assets as of March 31, 2021 consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ ​ Gross ​ ​ ​ ​ Cumulative ​ Net ​ Weighted ​ ​ Estimated Useful ​ Carrying ​ Accumulated ​ Translation ​ Carrying ​ Average ​ Life (in years) Value Amortization Adjustment Value Life R emaining (in years) Know-how ​ 8.5 ​ $ 13,000 ​ $ (2,678) ​ $ 654 ​ $ 10,976 ​ 6.75 Developed technology 7 ​ ​ 1,650 ​ ​ (1,100) ​ ​ — ​ ​ 550 ​ 3.84 Customer relationships 8.5 - 10 ​ 1,360 ​ (663) ​ ​ 6 ​ 703 ​ 6.83 Non-compete agreements ​ 5.5 ​ ​ 340 ​ ​ (119) ​ ​ 14 ​ ​ 235 ​ 3.75 Trade names 3 ​ 50 ​ (50) ​ ​ — ​ — ​ — Total ​ ​ $ 16,400 ​ $ (4,610) ​ $ 674 ​ $ 12,464 ​ ​ ​ Acquired intangible assets as of December 31, 2020 consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Gross ​ ​ ​ ​ Cumulative ​ Net ​ Weighted ​ ​ Estimated Useful ​ Carrying ​ Accumulated ​ Translation ​ Carrying ​ Average ​ Life (in years) Value Amortization Adjustment Value Life R emaining (in years) Know-how ​ 8.5 ​ $ 13,000 ​ $ (2,296) ​ $ 1,374 ​ $ 12,078 ​ 6.99 Developed technology 7 ​ ​ 1,650 ​ ​ (1,036) ​ ​ — ​ ​ 614 ​ 4.09 Customer relationships 8.5 - 10 ​ 1,360 ​ (618) ​ ​ 12 ​ 754 ​ 7.08 Non-compete agreements ​ 5.5 ​ ​ 340 ​ ​ (102) ​ ​ 31 ​ ​ 269 ​ 3.99 Trade names 3 ​ 50 ​ (49) ​ ​ — ​ 1 ​ 0.08 Total ​ ​ $ 16,400 ​ $ (4,101) ​ $ 1,417 ​ $ 13,716 ​ ​ ​ The Company recorded amortization expense of $0.5 million and $0.5 million for the three months ended March 31, 2021 and 2020, respectively. Amortization relating to developed technology is recorded within research and development expenses, amortization of customer relationships is recorded within selling, general, and administrative expenses, amortization of trade names is recorded within selling, general and administrative expenses, amortization of non-compete agreements is recorded within selling, general, and administrative expenses, and amortization of know-how is recorded within cost of product revenue. Future estimated amortization expense of acquired intangible assets as of March 31, 2021 is as follows (in thousands): ​ ​ ​ ​ ​ For the Years Ended December 31, ​ Estimated Amortization Expense Current year (2021) ​ $ 1,504 2022 ​ 1,930 2023 ​ 1,848 2024 ​ ​ 1,733 2025 ​ 1,617 Thereafter ​ 3,832 ​ ​ $ 12,464 ​

Related party transactions

Related party transactions	3 Months Ended
	Mar. 31, 2021
Related party transactions
Related party transactions	​ 16. Related party transactions ​ ​ During the year ended December 31, 2017, Harvard University became a related party because a member of the Company’s Board of Directors is affiliated with Harvard University. Revenue recorded from sales to Harvard University was less than $0.1 million during both the three months ended March 31, 2021 and 2020.

Accumulated other comprehensive

Accumulated other comprehensive income (loss)	3 Months Ended
	Mar. 31, 2021
Accumulated other comprehensive income (loss)
Accumulated other comprehensive income (loss)	​ 17. Accumulated other comprehensive income (loss) The following shows the changes in the components of accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 which consisted of only foreign currency translation adjustments for the periods shown (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Cumulative ​ Other ​ ​ Translation ​ Comprehensive ​ ​ Adjustment ​ Income (Loss) Balance - December 31, 2020 ​ $ 2,434 ​ $ 2,434 Current period accumulated other comprehensive loss ​ ​ (1,251) ​ ​ (1,251) Balance - March 31, 2021 ​ $ 1,183 ​ $ 1,183 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Cumulative ​ Other ​ ​ Translation ​ Comprehensive ​ ​ Adjustment ​ Loss Balance - December 31, 2019 ​ $ (153) ​ $ (153) Current period accumulated other comprehensive loss ​ ​ (1,047) ​ ​ (1,047) Balance - March 31, 2020 ​ $ (1,200) ​ $ (1,200) ​

Subsequent events

Subsequent events	3 Months Ended
	Mar. 31, 2021
Subsequent events
Subsequent events	18. Subsequent events The Company had no significant subsequent events for the period March 31, 2021 through the filing date of this Quarterly Report on Form 10-Q. ​ ​ ​

Significant accounting polici_2

Significant accounting policies (Policies)	3 Months Ended
	Mar. 31, 2021
Significant accounting policies
Principles of consolidation	Principles of consolidation The condensed consolidated financial statements have been prepared in accordance with U.S. GAAP and include the accounts of Quanterix Corporation and its wholly-owned subsidiaries. All material intercompany transactions and balances have been eliminated in consolidation.
Use of estimates	Use of estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. In making those estimates and assumptions, the Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. The Company’s significant estimates included in the preparation of the consolidated financial statements are related to revenue recognition, fair value of assets acquired and liabilities assumed in acquisitions, valuation allowances recorded against deferred tax assets, and valuation of inventory. Actual results could differ from those estimates.
Foreign Currency	Foreign currency
Income taxes	Income taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company's consolidated financial statements or tax returns. Under this method, deferred tax assets and liabilities are determined based on differences between the consolidated financial statement carrying amounts and the tax bases of the assets and liabilities using the enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance against deferred tax assets is recorded if, based on the weight of the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company accounts for uncertain tax positions in accordance with the provisions of Accounting Standards Codification (ASC) 740, Income Taxes ​
Business combinations	Business combinations Under the acquisition method of accounting, the Company generally recognizes the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values on the date of acquisition. The fair values assigned, defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between willing market participants, are based on estimates and assumptions determined by management. The excess consideration over the aggregate value of tangible and intangible assets, net of liabilities assumed, is recorded as goodwill. These valuations require significant estimates and assumptions, especially with respect to intangible assets. The Company typically uses the discounted cash flow method to value acquired intangible assets. This method requires significant management judgment to forecast future operating results and establish residual growth rates and discount factors. The estimates used to value and amortize intangible assets are consistent with the plans and estimates that are used to manage the business and are based on available historical information and industry estimates and averages. If the subsequent actual results and updated projections of the underlying business activity change compared with the assumptions and projections used to develop these values, the Company could experience impairment charges. In addition, the Company has estimated the economic lives of certain acquired assets and these lives are used to calculate depreciation and amortization expense. If estimates of the economic lives change, depreciation or amortization expenses could be accelerated or slowed.
Restricted Cash	Restricted cash Restricted cash primarily represents collateral for a letter of credit issued as security for the lease for the Company’s headquarters in Billerica, Massachusetts, and to secure the Company’s corporate credit card program. The restricted cash is long term in nature as the Company will not have access to the funds until more than one year from March 31, 2021.
Recent accounting pronouncements	Recent accounting pronouncements The Company is considered to be an “emerging growth company” (EGC) as defined in the Jumpstart Our Business Startups Act of 2012, as amended (JOBS Act). The JOBS Act provides that an EGC can take advantage of an extended transition period for complying with new or revised accounting standards. Thus, an EGC can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company may remain an EGC until the last day of the fiscal year in which the fifth anniversary of the closing of the initial public offering occurs, although if the market value the Company’s common stock that is held by non-affiliates exceeds $700 million as of any June 30 before that time or if the Company has annual gross revenues of $1.07 billion or more in any fiscal year, the Company would cease to be an EGC as of December 31 of the applicable year. The Company also would cease to be an EGC if it issues more than $1 billion of non-convertible debt over a three-year period. The Company has elected to avail itself of this extended transition period and, as a result, the Company will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for other public companies so long as the Company remains an EGC. Recently Adopted In June 2016, the Financial Accounting Standards Board (FASB) established Topic 326 , Financial Instruments — Credit Losses: Measurement of Credit Losses on Financial Instruments looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables and available-for-sale debt securities. The Company early adopted ASU 2016-13 on January 1, 2021 using the modified retrospective approach. The Company’s consolidated financial statements for prior-year periods have not been revised and are reflective of the credit loss requirements which were in effect for that period. The adoption of ASU 2016-13 did not have a material impact on the Company’s consolidated financial statements. ​ In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract . This ASU addresses the accounting for implementation, setup and other upfront costs paid by a customer in a cloud computing or hosting arrangement. The guidance aligns the accounting treatment of these costs incurred in a hosting arrangement treated as a service contract with the requirements for capitalization and amortization costs to develop or obtain internal-use software. The Company adopted ASU 2018-15 on January 1, 2021 using the prospective method. The Adoption of ASU 2018-15 did not have a material impact on the Company’s consolidated financial statements. ​ In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes Income Taxes There have been no other material changes to the significant accounting policies and recent accounting pronouncements previously disclosed in the 2020 Annual Report on Form 10-K.

Revenue recognition (Tables)

Revenue recognition (Tables)	3 Months Ended
	Mar. 31, 2021
Revenue recognition
Schedule of disaggregated revenue	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2021 (in thousands) NA EMEA Asia Pacific Total Product revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments $ 3,756 ​ $ 2,833 ​ $ 372 ​ $ 6,961 Consumable and other products ​ 6,911 ​ ​ 3,493 ​ ​ 883 ​ ​ 11,287 Totals $ 10,667 $ 6,326 $ 1,255 $ 18,248 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties $ 971 ​ $ 438 ​ $ 62 ​ $ 1,471 Research services ​ 3,558 ​ ​ 728 ​ ​ 12 ​ 4,298 Other services ​ 456 ​ ​ 184 ​ ​ — ​ ​ 640 Totals ​ $ 4,985 ​ $ 1,350 ​ $ 74 ​ $ 6,409 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 187 ​ $ 74 ​ $ — ​ $ 261 Totals $ 187 $ 74 $ — $ 261 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, 2020 (in thousands) NA EMEA Asia Pacific Total Product revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments $ 1,753 $ 726 $ 1,209 $ 3,688 Consumable and other products ​ 2,924 ​ 2,704 ​ 517 ​ 6,145 Totals $ 4,677 $ 3,430 $ 1,726 $ 9,833 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties $ 748 $ 379 $ 52 $ 1,179 Research services ​ 3,667 ​ 82 ​ 538 ​ 4,287 Other services ​ 231 ​ 60 ​ 5 ​ 296 Totals ​ $ 4,646 ​ $ 521 ​ $ 595 ​ $ 5,762 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 122 ​ $ 10 ​ $ — ​ $ 132 Totals $ 122 $ 10 $ — $ 132 ​
Schedule of changes in deferred revenue from contracts with customers	Changes in deferred revenue from contracts with customers were as follows (in thousands): ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 Balance at December 31, 2020 $ 5,998 Deferral of revenue ​ 2,669 Recognition of deferred revenue ​ (1,471) Balance at March 31, 2021 $ 7,196
Schedule of costs to obtain a contract	​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 Balance at December 31, 2020 $ 248 Deferral of costs to obtain a contract ​ 88 Recognition of costs to obtain a contract ​ (160) Balance at March 31, 2021 $ 176 ​
Schedule of summary of the activity under WP2	The following table summarizes the activity under WP2 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ December 31, 2020 ​ ​ ​ ​ ​ ​ Total grant revenue from research and development activities $ 6,653 ​ $ 4,362 Total proceeds used for assets ​ 4,622 ​ ​ 826 Total deferred proceeds for assets ​ 1,159 ​ ​ 2,478 Total deferred grant revenue ​ 500 ​ ​ 304 Total recognized $ 12,934 ​ $ 7,970 ​ ​ ​ ​ ​ ​ Total recognized $ 12,934 ​ $ 7,970 Total amount accrued ​ (2,961) ​ ​ (2,968) Total cash received $ 9,973 ​ $ 5,002 ​ ​ ​ ​ ​ ​ Total proceeds received $ 9,973 ​ $ 5,002 Total proceeds reasonably assured ​ 8,227 ​ ​ 13,198 Total WP2 grant amount $ 18,200 ​ $ 18,200

Net loss per share (Tables)

Net loss per share (Tables)	3 Months Ended
	Mar. 31, 2021
Net loss per share
Schedule of outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share	The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because to do so would be anti-dilutive (in common stock equivalent shares): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ 2021 2020 ​ Unvested restricted common stock and restricted stock units 563,810 561,786 ​ Outstanding stock options 2,428,268 2,840,525 Outstanding common stock warrants — 10,000 Total 2,992,078 3,412,311

Fair value of financial instr_2

Fair value of financial instruments (Tables)	3 Months Ended
	Mar. 31, 2021
Fair value of financial instruments
Schedule of fair value measurements	Fair value measurements as of March 31, 2021 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs Description Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 162,059 $ 162,059 ​ $ — $ — ​ ​ $ 162,059 ​ $ 162,059 ​ $ — ​ $ — ​ Fair value measurements as of December 31, 2020 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs Description Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 162,048 $ 162,048 ​ $ — $ — ​ $ 162,048 $ 162,048 ​ $ — $ —

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2021
Inventory
Summary of inventory	Inventory consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2021 2020 Raw materials ​ $ 5,608 ​ $ 5,265 ​ Work in process ​ 4,012 ​ 3,306 ​ Finished goods ​ 7,424 ​ 6,285 ​ Total ​ $ 17,044 ​ $ 14,856 ​

Allowance for Credit Losses (Ta

Allowance for Credit Losses (Tables)	3 Months Ended
	Mar. 31, 2021
Allowance for Credit Loss
Schedule of the allowance for credit losses	The following table provides a roll-forward of the allowance for credit losses for the three months ended March 31, 2021 that is deducted from the amortized cost basis of accounts receivable to present the net amount expected to be collected (in thousands): ​ ​ ​ ​ ​ Balance at January 1, 2021 ​ $ 370 Credit loss expense ​ ​ 20 Write-offs charged against allowances ​ ​ (48) Balance at March 31, 2021 ​ $ 342

Other accrued expenses and ot_2

Other accrued expenses and other non-current liabilities (Tables)	3 Months Ended
	Mar. 31, 2021
Other accrued expenses and other non-current liabilities
Summary of other accrued expenses	Other accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2021 2020 Accrued inventory purchases ​ $ 878 ​ $ 527 Accrued property and equipment purchases ​ ​ 1,532 ​ ​ 670 Accrued royalties ​ 1,124 ​ 1,845 Accrued professional services ​ 863 ​ 797 Accrued development costs ​ 241 ​ 323 Accrued other ​ 965 ​ 683 Total accrued expenses ​ $ 5,603 ​ $ 4,845
Summary of other non-current liabilities	Other non-current liabilities consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2021 2020 Deferred tax liabilities ​ $ 2,378 ​ $ 2,649 Total other non-current liabilities ​ $ 2,378 ​ $ 2,649

Warrants, stock-based compens_2

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units (Tables)	3 Months Ended
	Mar. 31, 2021
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Summary of share-based compensation expense for all stock awards	Stock-based compensation expense for all stock awards consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ ​ 2021 2020 ​ Cost of product revenue ​ $ 90 ​ $ 36 ​ Cost of service and other revenue ​ 110 ​ 68 ​ Research and development ​ 399 ​ 242 ​ Selling, general, and administrative ​ 2,787 ​ 1,763 ​ Total ​ $ 3,386 ​ $ 2,109 ​
Summary of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ Remaining contractual ​ Aggregate intrinsic value ​ Options exercise price life (in years) (in thousands) Outstanding at December 31, 2020 2,494,045 $ 17.73 ​ 7.27 ​ $ 71,760 Granted 241,713 ​ $ 69.97 ​ ​ ​ ​ ​ Exercised (281,324) ​ $ 10.93 ​ ​ ​ ​ ​ Cancelled (26,166) ​ $ 35.98 ​ ​ ​ ​ ​ Outstanding at March 31, 2021 2,428,268 ​ $ 23.52 ​ 7.37 ​ $ 88,387 Vested and expected to vest at March 31, 2021 2,428,268 ​ $ 23.52 ​ 7.37 ​ $ 88,387 Exercisable at March 31, 2021 ​ 1,428,652 ​ $ 14.31 ​ 6.43 ​ $ 63,050
Summary of restricted stock units activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ ​ ​ ​ grant date ​ ​ ​ ​ fair value ​ Shares per share Unvested RSUs as of December 31, 2020 478,581 $ 28.08 Granted 140,814 ​ $ 71.28 Vested (85,346) ​ $ 24.50 Cancelled (10,045) ​ $ 41.14 Unvested RSUs as of March 31, 2021 524,004 ​ $ 40.02

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2021
Leases
Summary of the lease costs recognized under ASC 842	The following table contains a summary of the lease costs recognized under ASC 842 and other information pertaining to the Company’s operating leases for the three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ Operating leases (in thousands) ​ 2021 ​ 2020 ​ Lease Costs (1) ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 671 ​ $ 660 ​ Total lease cost ​ $ 671 ​ $ 660 ​ ​ ​ ​ ​ ​ ​ ​ ​ Other information ​ ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 846 ​ $ 407 ​ Weighted average remaining lease term (years) ​ ​ 9.6 years ​ 10.3 years Weighted average discount rate ​ ​ 9.73% ​ ​ 9.73% ​ ​ ​ (1) Short-term lease costs and variable lease costs incurred by the Company for the three months ended March 31, 2021 and 2020 were immaterial, respectively.

Notes payable (Tables)

Notes payable (Tables)	3 Months Ended
	Mar. 31, 2021
Notes payable
Schedule of debt payment obligations due based on principal payments	As of March 31, 2021, debt payment obligations due based on principal payments are as follows (in thousands): ​ ​ ​ ​ ​ 2021 ​ $ 7,688 Total ​ $ 7,688

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets
Rollforward of goodwill balance	​ ​ ​ ​ ​ ​ Goodwill Balance as of December 31, 2020 ​ $ 10,460 Cumulative translation adjustment ​ ​ (527) Balance as of March 31, 2021 ​ $ 9,933
Summary of intangible assets	Acquired intangible assets as of March 31, 2021 consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ ​ Gross ​ ​ ​ ​ Cumulative ​ Net ​ Weighted ​ ​ Estimated Useful ​ Carrying ​ Accumulated ​ Translation ​ Carrying ​ Average ​ Life (in years) Value Amortization Adjustment Value Life R emaining (in years) Know-how ​ 8.5 ​ $ 13,000 ​ $ (2,678) ​ $ 654 ​ $ 10,976 ​ 6.75 Developed technology 7 ​ ​ 1,650 ​ ​ (1,100) ​ ​ — ​ ​ 550 ​ 3.84 Customer relationships 8.5 - 10 ​ 1,360 ​ (663) ​ ​ 6 ​ 703 ​ 6.83 Non-compete agreements ​ 5.5 ​ ​ 340 ​ ​ (119) ​ ​ 14 ​ ​ 235 ​ 3.75 Trade names 3 ​ 50 ​ (50) ​ ​ — ​ — ​ — Total ​ ​ $ 16,400 ​ $ (4,610) ​ $ 674 ​ $ 12,464 ​ ​ ​ Acquired intangible assets as of December 31, 2020 consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Gross ​ ​ ​ ​ Cumulative ​ Net ​ Weighted ​ ​ Estimated Useful ​ Carrying ​ Accumulated ​ Translation ​ Carrying ​ Average ​ Life (in years) Value Amortization Adjustment Value Life R emaining (in years) Know-how ​ 8.5 ​ $ 13,000 ​ $ (2,296) ​ $ 1,374 ​ $ 12,078 ​ 6.99 Developed technology 7 ​ ​ 1,650 ​ ​ (1,036) ​ ​ — ​ ​ 614 ​ 4.09 Customer relationships 8.5 - 10 ​ 1,360 ​ (618) ​ ​ 12 ​ 754 ​ 7.08 Non-compete agreements ​ 5.5 ​ ​ 340 ​ ​ (102) ​ ​ 31 ​ ​ 269 ​ 3.99 Trade names 3 ​ 50 ​ (49) ​ ​ — ​ 1 ​ 0.08 Total ​ ​ $ 16,400 ​ $ (4,101) ​ $ 1,417 ​ $ 13,716 ​ ​
Schedule of future estimated amortization expense of acquired intangible assets	Future estimated amortization expense of acquired intangible assets as of March 31, 2021 is as follows (in thousands): ​ ​ ​ ​ ​ For the Years Ended December 31, ​ Estimated Amortization Expense Current year (2021) ​ $ 1,504 2022 ​ 1,930 2023 ​ 1,848 2024 ​ ​ 1,733 2025 ​ 1,617 Thereafter ​ 3,832 ​ ​ $ 12,464

Accumulated other comprehensi_2

Accumulated other comprehensive income (loss) (Tables)	3 Months Ended
	Mar. 31, 2021
Accumulated other comprehensive income (loss)
Schedule of Accumulated Other Comprehensive Income (Loss)	The following shows the changes in the components of accumulated other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 which consisted of only foreign currency translation adjustments for the periods shown (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Cumulative ​ Other ​ ​ Translation ​ Comprehensive ​ ​ Adjustment ​ Income (Loss) Balance - December 31, 2020 ​ $ 2,434 ​ $ 2,434 Current period accumulated other comprehensive loss ​ ​ (1,251) ​ ​ (1,251) Balance - March 31, 2021 ​ $ 1,183 ​ $ 1,183 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ Cumulative ​ Other ​ ​ Translation ​ Comprehensive ​ ​ Adjustment ​ Loss Balance - December 31, 2019 ​ $ (153) ​ $ (153) Current period accumulated other comprehensive loss ​ ​ (1,047) ​ ​ (1,047) Balance - March 31, 2020 ​ $ (1,200) ​ $ (1,200)

Organization and operations (De

Organization and operations (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Feb. 03, 2021	Aug. 06, 2020	Mar. 31, 2021	Dec. 31, 2020
Initial Public Offering
Common stock, par value			$ 0.001	$ 0.001
Underwritten public offering
Initial Public Offering
Stock Issued During Period, Shares, New Issues	4.1	3
Common stock, par value	$ 0.001	$ 0.001
Gross Proceeds From Issuance Of Common Stock	$ 287,500	$ 97,600
Stock issuance cost	17,800	6,200
Sale of common stock in at-the-market offering, net	$ 269,700	$ 91,400	$ 269,718

Revenue recognition - Customers

Revenue recognition - Customers (Details)	3 Months Ended
	Mar. 31, 2021
Minimum
Revenue recognition
Period of payment	30 days
Maximum
Revenue recognition
Period of payment	45 days

Revenue recognition - Disaggreg

Revenue recognition - Disaggregated revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue recognition
Total revenue	$ 27,209	$ 15,727
Product revenue
Revenue recognition
Total revenue	18,248	9,833
Product revenue | NA
Revenue recognition
Total revenue	10,667	4,677
Product revenue | EMEA
Revenue recognition
Total revenue	6,326	3,430
Product revenue | Asia Pacific
Revenue recognition
Total revenue	1,255	1,726
Instruments
Revenue recognition
Total revenue	6,961	3,688
Instruments | NA
Revenue recognition
Total revenue	3,756	1,753
Instruments | EMEA
Revenue recognition
Total revenue	2,833	726
Instruments | Asia Pacific
Revenue recognition
Total revenue	372	1,209
Consumable and other products
Revenue recognition
Total revenue	11,287	6,145
Consumable and other products | NA
Revenue recognition
Total revenue	6,911	2,924
Consumable and other products | EMEA
Revenue recognition
Total revenue	3,493	2,704
Consumable and other products | Asia Pacific
Revenue recognition
Total revenue	883	517
Service and other revenue
Revenue recognition
Total revenue	6,409	5,762
Service and other revenue | NA
Revenue recognition
Total revenue	4,985	4,646
Service and other revenue | EMEA
Revenue recognition
Total revenue	1,350	521
Service and other revenue | Asia Pacific
Revenue recognition
Total revenue	74	595
Service-type warranties
Revenue recognition
Total revenue	1,471	1,179
Service-type warranties | NA
Revenue recognition
Total revenue	971	748
Service-type warranties | EMEA
Revenue recognition
Total revenue	438	379
Service-type warranties | Asia Pacific
Revenue recognition
Total revenue	62	52
Research services
Revenue recognition
Total revenue	4,298	4,287
Research services | NA
Revenue recognition
Total revenue	3,558	3,667
Research services | EMEA
Revenue recognition
Total revenue	728	82
Research services | Asia Pacific
Revenue recognition
Total revenue	12	538
Other services
Revenue recognition
Total revenue	640	296
Other services | NA
Revenue recognition
Total revenue	456	231
Other services | EMEA
Revenue recognition
Total revenue	184	60
Other services | Asia Pacific
Revenue recognition
Total revenue		5
Collaboration and license revenue
Revenue recognition
Total revenue	261	132
Collaboration and license revenue | NA
Revenue recognition
Total revenue	187	122
Collaboration and license revenue | EMEA
Revenue recognition
Total revenue	74	$ 10
Grant revenue
Revenue recognition
Total revenue	$ 2,291

Revenue recognition - Future pe

Revenue recognition - Future performance obligations (Details) - USD ($) $ in Millions	Mar. 31, 2021	Mar. 31, 2020
Transaction Price Allocated to Future Performance Obligations
Amount of transaction price allocated to performance obligations	$ 7.2	$ 5.8
Service-type warranties and research services
Transaction Price Allocated to Future Performance Obligations
Amount of transaction price allocated to performance obligations	5.9
Undelivered licenses of intellectual property
Transaction Price Allocated to Future Performance Obligations
Amount of transaction price allocated to performance obligations	0.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Transaction Price Allocated to Future Performance Obligations
Amount of transaction price allocated to performance obligations	$ 6.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Transaction Price Allocated to Future Performance Obligations
Amount of transaction price allocated to performance obligations	$ 0.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	24 months

Revenue recognition - Changes i

Revenue recognition - Changes in deferred revenue from contracts with customers (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Changes in deferred revenue from contracts with customers
Balance at beginning of period	$ 5,998
Deferral of revenue	2,669
Recognition of deferred revenue	(1,471)
Balance at end of period	$ 7,196

Revenue recognition - Costs to

Revenue recognition - Costs to obtain a contract (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Change in the balance of costs to obtain a contract
Balance at beginning of period	$ 248
Deferral of costs to obtain a contract	88
Recognition of costs to obtain a contract	(160)
Balance at end of period	$ 176

Revenue recognition - Practical

Revenue recognition - Practical expedients (Details)	3 Months Ended
	Mar. 31, 2021
Revenue recognition
Revenue, Practical Expedient, Financing Component [true false]	true
Revenue, Remaining Performance Obligation, Optional Exemption, Performance Obligation [true false]	true

Revenue recognition - Grant rev

Revenue recognition - Grant revenue (Details) - USD ($) $ in Thousands	Sep. 29, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Total revenue		$ 27,209	$ 15,727
Research and Development Expense		6,683	$ 4,268
RADx WP2
Contract value	$ 18,200
Research and Development Expense		1,800
Grant revenue
Total revenue		2,291
Grant revenue | RADx WP2
Total revenue		6,653		$ 4,362
Contract value		$ 18,200		$ 18,200

Revenue recognition - Summarize

Revenue recognition - Summarizes the activity under WP2 (Details) - USD ($) $ in Thousands	Sep. 29, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Total revenue		$ 27,209	$ 15,727
Grant revenue
Disaggregation of Revenue [Line Items]
Total revenue		2,291
RADx WP2
Disaggregation of Revenue [Line Items]
Total WP2 grant amount	$ 18,200
RADx WP2 | Grant revenue
Disaggregation of Revenue [Line Items]
Total revenue		6,653		$ 4,362
Total proceeds used for assets		4,622		826
Total deferred proceeds for assets		1,159		2,478
Total deferred grant revenue		500		304
Total recognized		12,934		7,970
Total amount accrued		(2,961)		(2,968)
Total cash received		9,973		5,002
Total proceeds received		9,973		5,002
Total proceeds reasonably assured		8,227		13,198
Total WP2 grant amount		$ 18,200		$ 18,200

Net loss per share (Details)

Net loss per share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Net loss per share
Number of dilutive securities excluded in the calculation of diluted net loss per share	2,992,078	3,412,311
Common stock
Net loss per share
Obligation to issue warrants, in shares	93,341	93,341
Unvested restricted common stock and restricted stock units
Net loss per share
Number of dilutive securities excluded in the calculation of diluted net loss per share	563,810	561,786
Outstanding stock options
Net loss per share
Number of dilutive securities excluded in the calculation of diluted net loss per share	2,428,268	2,840,525
Warrants
Net loss per share
Number of dilutive securities excluded in the calculation of diluted net loss per share		10,000

Fair value of financial instr_3

Fair value of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash equivalents	$ 162,059	$ 162,048
Total	162,059	162,048
Level 1
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash equivalents	162,059	162,048
Total	$ 162,059	$ 162,048

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory
Raw Materials	$ 5,608	$ 5,265
Work in process	4,012	3,306
Finished goods	7,424	6,285
Total	$ 17,044	$ 14,856

Allowance for Credit Losses (De

Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Allowance for Credit Loss
Allowance for Doubtful Accounts Receivable, Beginning Balance	$ 370
Credit loss expense	20
Write-offs charged against allowances	(48)
Allowance for Doubtful Accounts Receivable, Ending Balance	342
Accounts receivable	$ 14,936	$ 17,184

Other accrued expenses and ot_3

Other accrued expenses and other non-current liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other accrued expenses and other non-current liabilities
Accrued inventory purchases	$ 878	$ 527
Accrued property and equipment purchases	1,532	670
Accrued royalties	1,124	1,845
Accrued professional services	863	797
Accrued development costs	241	323
Accrued other	965	683
Total accrued expenses	$ 5,603	$ 4,845

Other accrued expenses and ot_4

Other accrued expenses and other non-current liabilities - Other non-current liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other non-current liabilities
Deferred tax liabilities	$ 2,378	$ 2,649
Total other non-current liabilities	$ 2,378	$ 2,649

Warrants, stock-based compens_3

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units- Warrants (Details) - Warrants - USD ($)	Jan. 10, 2021	Mar. 31, 2021
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Warrants And Rights, Exercised	10,000
Exercise of common stock warrants (in shares)	7,347
Warrants and Rights Outstanding		$ 0

Warrants, stock-based compens_4

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units - Share-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Share-based compensation expense	$ 3,386	$ 2,109
Cost of product revenue
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Share-based compensation expense	90	36
Cost of service and other revenue
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Share-based compensation expense	110	68
Research and development
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Share-based compensation expense	399	242
General and administrative
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Share-based compensation expense	$ 2,787	$ 1,763

Warrants, stock-based compens_5

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units - Stock-based award plans (Details) - shares	Jan. 01, 2021	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2017
2007 Plan
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Shares available for grant under the plan (in shares)		0
2017 Plan
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Shares authorized under the plan (in shares)					1,042,314
Additional shares authorized	1,273,501
Shares available for grant under the plan (in shares)		1,637,976
Annual increase in the shares available for grant under the plan (as a percent of shares of common stock outstanding)		4.00%
2017 ESPP
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Shares authorized under the plan (in shares)				848,269
Shares available for grant under the plan (in shares)		1,149,407
Option periods		6 months
Annual increase in the shares available for grant under the plan (as a percent of shares of common stock outstanding)				1.00%
Increase in the shares available for grant under the plan (in shares)	318,375
Outstanding stock options
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Options outstanding (in shares)		2,428,268	2,494,045
Outstanding stock options | 2007 Plan
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Options outstanding (in shares)		736,958
Shares authorized under the plan (in shares)					2,490,290

Warrants, stock-based compens_6

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units - Stock options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Aggregate intrinsic value
Share-based compensation expense	$ 3,386	$ 2,109
Outstanding stock options
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Options expiration period (in years)	10 years
Number outstanding
Outstanding at the beginning of the period (in shares)	2,494,045
Granted (in shares)	241,713
Exercised (in shares)	(281,324)
Cancelled or forfeited (in shares)	(26,166)
Outstanding at the end of the period (in shares)	2,428,268		2,494,045
Vested and expected to vest at the end of the period (in shares)	2,428,268
Exercisable at the end of the period (in shares)	1,428,652
Weighted-average exercise price
Outstanding at the beginning of the period (in dollars per share)	$ 17.73
Granted (in dollars per share)	69.97
Exercised (in dollars per share)	10.93
Cancelled or forfeited (in dollars per share)	35.98
Outstanding at the end of the period (in dollars per share)	23.52		$ 17.73
Vested and expected to vest at the end of the period (in dollars per share)	23.52
Exercisable at the end of the period (in dollars per share)	$ 14.31
Remaining contractual life
Outstanding (in years)	7 years 4 months 13 days		7 years 3 months 7 days
Vested and expected to vest at the end of the period (in years)	7 years 4 months 13 days
Exercisable at the end of the period (in years)	6 years 5 months 4 days
Aggregate intrinsic value
Outstanding at the beginning of the period	$ 71,760
Exercised	16,200	$ 1,100
Outstanding at the end of the period	88,387		$ 71,760
Vested and expected to vest at the end of the period	88,387
Exercisable at the end of the period	$ 63,050
Weighted-average fair value of options granted	$ 32.83	$ 11.82
Share-based compensation expense	$ 1,500	$ 1,100
Intrinsic value of stock options exercised	$ 16,200	$ 1,100
Outstanding stock options | Subject to a four year vesting schedule with 25% vesting on the first anniversary and the remaining vesting ratably on a monthly basis over the remaining three years
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Vesting period (in years)	4 years
Vesting percentage 1 (as a percent)	25.00%
Outstanding stock options | Remaining 75% vesting ratably on a monthly basis over the remaining three years
Warrants, stock-based compensation, stock options, restricted stock and restricted stock units
Vesting period (in years)	3 years
Vesting percentage 1 (as a percent)	75.00%

Warrants, stock-based compens_7

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units - Restricted stock (Details) - Restricted stock - shares	1 Months Ended	3 Months Ended
	Jan. 31, 2015	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		0
2007 Plan | Executive
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	781,060
2007 Plan | Executive | Subject to a four year vesting schedule with 25% vesting on the first anniversary and the remaining vesting ratably on a monthly basis over the remaining three years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Vesting percentage 1 (as a percent)	25.00%
2007 Plan | Executive | Remaining 75% vesting ratably on a monthly basis over the remaining three years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Vesting percentage 1 (as a percent)	75.00%

Warrants, stock-based compens_8

Warrants, stock-based compensation, stock options, restricted stock and restricted stock units - Restricted stock units (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Weighted-average grant date fair value per share
Share-based compensation expense	$ 3,386	$ 2,109
Restricted stock units
Number of restricted stock units
Unvested restricted common stock at the beginning of the period (in shares)	478,581
Granted (in shares)	140,814
Vested (in shares)	(85,346)
Cancelled (in shares)	(10,045)
Unvested restricted common stock at the end of the period (in shares)	524,004
Weighted-average grant date fair value per share
Unvested restricted common stock at the beginning of the period (in dollars per share)	$ 28.08
Granted (in dollars per share)	71.28
Vested (in dollars per share)	24.50
Cancelled (in dollars per share)	41.14
Unvested restricted common stock at the end of the period (in dollars per share)	$ 40.02
Share-based compensation expense	$ 1,700	$ 900
Total unrecognized compensation cost related to unvested stock awards	$ 19,900
Period of recognition of unrecognized compensation cost	3 years 1 month 6 days
Restricted stock
Number of restricted stock units
Granted (in shares)	0
Unvested restricted common stock at the end of the period (in shares)	39,806
Weighted-average grant date fair value per share
Unvested restricted common stock at the end of the period (in dollars per share)	$ 3.12
2017 Plan | Restricted stock units
Number of restricted stock units
Granted (in shares)	140,814
2017 Plan | Restricted stock units | Subject to a four year vesting schedule with 25% vesting on the first anniversary and the remaining vesting ratably on a monthly basis over the remaining three years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period 1	4 years
Vesting period 2	3 years
Vesting percentage 1 (as a percent)	25.00%
Vesting percentage 2 (as a percent)	75.00%
Number of restricted stock units
Granted (in shares)	126,007
2017 Plan | Restricted stock units | Vested on May 31, 2020
Number of restricted stock units
Granted (in shares)	1,187
2017 Plan | Restricted stock units | Vest on December 31, 2021
Number of restricted stock units
Granted (in shares)	13,620

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Leases
Right-of-use assets	$ 11,870	$ 11,995
Long term lease liabilities	$ 21,552	$ 21,891

Leases - Lease costs recognized

Leases - Lease costs recognized (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lease Costs
Operating lease costs	$ 671	$ 660
Total lease cost	671	660
Operating cash flows used for operating leases	$ 846	$ 407
Weighted average remaining lease term	9 years 7 months 6 days	10 years 3 months 18 days
Weighted average discount rate	9.73%	9.73%

Commitments and contingencies -

Commitments and contingencies - License agreements and Lease commitments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Tufts | License agreements
License agreements
Royalty expense	$ 0.5	$ 0.2

Commitments and contingencies_2

Commitments and contingencies - Development and supply agreement and Legal contingencies (Details)	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Commitments and contingencies
Period to purchase minimum number of commercial units	7 years
Issuance of supply warrants on termination of agreement, number (in shares) | shares	93,341
Issuance of supply warrants on termination of agreement, value per share (in dollars per share) | $ / shares	$ 0.003214

Notes payable (Details)

Notes payable (Details) - USD ($) $ in Millions	Apr. 14, 2014	Mar. 31, 2021	Mar. 31, 2020
Maximum
Long Term Debt
Non-cash interest expense		$ 0.1	$ 0.1
Loan agreement
Long Term Debt
Additional amounts available to borrow		$ 0
Interest rate (as a percent)	8.00%
Prime rate | Loan agreement
Long Term Debt
Margin on variable interest rate (as a percent)	(5.25%)

Notes payable - Debt payment ob

Notes payable - Debt payment obligations (Details) $ in Thousands	Mar. 31, 2021USD ($)
Debt payment obligations due based on principal payments
2021	$ 7,688
Debt payment obligations	$ 7,688

Collaboration and license arr_2

Collaboration and license arrangements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Collaboration and license arrangements
Revenue	$ 27,209	$ 15,727
Deferred revenue	500		$ 500
Joint development and license agreement | Maximum
Collaboration and license arrangements
Revenue	$ 300	$ 100
Abbot license agreement
Collaboration and license arrangements
Number of days notice to terminate agreement	60 days
Initial license fee receivable	$ 10,000

Employee benefit plans (Details

Employee benefit plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Employee benefit plans
Contribution made to the 401 (k) Plan	$ 0.2	$ 0.1

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Rollforward of goodwill balance
Balance as of beginning of period	$ 10,460
Cumulative translation adjustment	(527)
Balance as of end of period	9,933	$ 10,460
Purchased intangible assets
Gross Carrying Value	16,400	16,400
Accumulated Amortization	(4,610)	(4,101)
Cumulative Translation Adjustment	674	1,417
Net Carrying Value	12,464	$ 13,716
Amortization expense	500
Estimated amortization expense
Current year (2021)	1,504
2022	1,930
2023	1,848
2024	1,733
2025	1,617
Thereafter	3,832
Estimated Amortization Expenses	$ 12,464
Developed technology
Purchased intangible assets
Estimated Useful Life	7 years	7 years
Gross Carrying Value	$ 1,650	$ 1,650
Accumulated Amortization	(1,100)	(1,036)
Net Carrying Value	$ 550	$ 614
Weighted average life remaining	3 years 10 months 2 days	4 years 1 month 2 days
Customer relationships
Purchased intangible assets
Gross Carrying Value	$ 1,360	$ 1,360
Accumulated Amortization	(663)	(618)
Cumulative Translation Adjustment	6	12
Net Carrying Value	$ 703	$ 754
Weighted average life remaining	6 years 9 months 29 days	7 years 29 days
Trade names
Purchased intangible assets
Estimated Useful Life	3 years	3 years
Gross Carrying Value	$ 50	$ 50
Accumulated Amortization	$ (50)	(49)
Net Carrying Value		$ 1
Weighted average life remaining		29 days
Know How
Purchased intangible assets
Estimated Useful Life	8 years 6 months	8 years 6 months
Gross Carrying Value	$ 13,000	$ 13,000
Accumulated Amortization	(2,678)	(2,296)
Cumulative Translation Adjustment	654	1,374
Net Carrying Value	$ 10,976	$ 12,078
Weighted average life remaining	6 years 9 months	6 years 11 months 26 days
Noncompete Agreements
Purchased intangible assets
Estimated Useful Life	5 years 6 months	5 years 6 months
Gross Carrying Value	$ 340	$ 340
Accumulated Amortization	(119)	(102)
Cumulative Translation Adjustment	14	31
Net Carrying Value	$ 235	$ 269
Weighted average life remaining	3 years 9 months	3 years 11 months 26 days
Maximum | Customer relationships
Purchased intangible assets
Estimated Useful Life	10 years	10 years
Minimum | Customer relationships
Purchased intangible assets
Estimated Useful Life	8 years 6 months	8 years 6 months

Underwritten public offerings (

Underwritten public offerings (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Feb. 03, 2021	Aug. 06, 2020	Mar. 31, 2021	Dec. 31, 2020
Subsidiary or Equity Method Investee [Line Items]
Common stock, par value			$ 0.001	$ 0.001
Underwritten public offering
Subsidiary or Equity Method Investee [Line Items]
Stock Issued During Period, Shares, New Issues	4.1	3
Common stock, par value	$ 0.001	$ 0.001
Gross proceeds	$ 287,500	$ 97,600
Stock issuance cost	17,800	6,200
Proceeds from sale of common stock, net of issuance costs	$ 269,700	$ 91,400	$ 269,718

Related party transactions (Det

Related party transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Tufts | License Agreement
Related party transactions
Royalty Expense	$ 0.5	$ 0.2
Harvard University | Maximum
Related party transactions
Related party revenue	$ 0.1	$ 0.1

Accumulated other comprehensi_3

Accumulated other comprehensive income (loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Current period accumulated other comprehensive loss	$ (1,251)	$ (1,047)
Cumulative Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,434	(153)
Current period accumulated other comprehensive loss	(1,251)	(1,047)
Ending Balance	1,183	(1,200)
Accumulated other comprehensive income (loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	2,434	(153)
Current period accumulated other comprehensive loss	(1,251)	(1,047)
Ending Balance	$ 1,183	$ (1,200)