Quanterix Corp 10-K

Item 9A. CONTROLS AND PROCEDURES Disclosure Controls and Procedures We have established disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act that are designed to provide reasonable assurance that information required to be disclosed in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the rules and forms of the SEC and to ensure that such information is accumulated and communicated to management, including our Chief Executive Officer (principal executive officer) and Chief Financial Officer (principal financial officer), to allow timely decisions regarding required disclosures. Under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, we conducted an evaluation of the effectiveness of our disclosure controls and procedures as of December 31, 2021. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at a reasonable assurance level as of December 31, 2021. Management’s Report on Internal Control over Financial Reporting Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as this term is defined in Rule 13a-15(f) and 15d-15(f) under the Exchange Act. All internal control systems, no matter how well designed, have inherent limitations. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation. Under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting as of December 31, 2021 based on the framework set forth in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 Framework). Based on our evaluation under the framework set forth in Internal Control-Integrated Framework , our management concluded that our internal control over financial reporting was effective at the reasonable assurance level as of December 31, 2021. The Company’s independent registered public accounting firm, Ernst & Young LLP, has also issued an audit report on the Company’s internal controls over financial reporting, which is included elsewhere in this Annual Report on Form 10-K. Changes in Internal Control over Financial Reporting An evaluation was also performed under the supervision and with the participation of our management, including the principal executive officer and principal financial officer, of any change in our internal controls over financial reporting that occurred during our last fiscal quarter and that has materially affected, or is reasonably likely to affect, our internal controls over financial reporting. There has been no change in our internal controls over financial reporting during the fiscal quarter ended December 31, 2021 that has materially affected, or is reasonably likely to materially affect, our internal controls over financial reporting. ​ 85 Table of Contents REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM To the Shareholders and the Board of Directors of Quanterix Corporation Opinion on Internal Control over Financial Reporting We have audited Quanterix Corporation’s internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, Quanterix Corporation (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2021, based on the COSO criteria. We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of Quanterix Corporation as of December 31, 2021 and 2020, the related consolidated statements of operations, comprehensive loss, cash flows and stockholders’ equity for each of the three years in the period ended December 31, 2021, and the related notes and financial statement schedule listed in the Index at Item 15(2) and our report dated March 1, 2022 expressed an unqualified opinion thereon. Basis for Opinion The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Annual Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion. Definition and Limitations of Internal Control Over Financial Reporting A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. /s/ Ernst & Young LLP ​ ​ Boston, Massachusetts March 1, 2022 Item 9B. OTHER INFORMATION Not applicable. 86 Table of Contents Item 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS Not applicable. PART III Item 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE The information required by this Item 10 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2022 Annual Meeting of Stockholders and is incorporated herein by reference. Item 11. EXECUTIVE COMPENSATION The information required by this Item 11 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2022 Annual Meeting of Stockholders and is incorporated herein by reference. Item 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS The information required by this Item 12 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2022 Annual Meeting of Stockholders and is incorporated herein by reference. Item 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE The information required by this Item 13 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2022 Annual Meeting of Stockholders and is incorporated herein by reference. Item 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES The information required by this Item 14 will be included in our definitive proxy statement to be filed with the SEC with respect to our 2022 Annual Meeting of Stockholders and is incorporated herein by reference. PART IV Item 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES (1) Financial Statements The consolidated financial statements are included beginning on page F-1 attached hereto and are filed as part of this Annual Report on Form 10-K. 87 Table of Contents (2) Financial Statement Schedules Schedule II – Valuations and Qualifying Accounts ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at ​ ​ Charged ​ ​ ​ ​ ​ Balance at Description ​ Beginning of Period (in thousands) ​ ​ to Costs and Expenses (in thousands) ​ ​ Deductions (in thousands) ​ ​ End of Period (in thousands) Allowance for credit losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021 $ 370 ​ $ 213 ​ $ (164) ​ $ 419 Year ended December 31, 2020 $ 162 ​ $ 493 ​ $ (285) ​ $ 370 Year ended December 31, 2019 $ 36 ​ $ 160 ​ $ (34) ​ $ 162 (3) Exhibits The following is a list of exhibits filed as part of this Annual Report on Form 10-K: Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 3.1 ​ Amended and Restated Certificate of Incorporation ​ ​ ​ 8-K ​ 12/15/2017 ​ 001-38319 3.2 ​ Restated Bylaws ​ ​ ​ 8-K ​ 12/15/2017 ​ 001-38319 4.1 ​ Description of Securities ​ ​ ​ 10-K ​ 3/13/2020 ​ 001-38319 4.2 ​ Form of Common Stock Certificate ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 4.3 ​ Fourth Amended and Restated Registration Rights Agreement, dated as of June 2, 2017, by and among the Registrant and the investors named therein ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.1.1+ ​ 2007 Stock Option and Grant Plan, as amended ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.1.2+ ​ Form of Incentive Stock Option Agreement under the 2007 Stock Option and Grant Plan, as amended ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.1.3+ ​ Form of Non-qualified Stock Option Agreement under the 2007 Stock Option and Grant Plan, as amended ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.1.4+ ​ Form of Restricted Stock Agreement under the 2007 Stock Option and Grant Plan, as amended ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.2.1+ ​ 2017 Employee, Director and Consultant Equity Incentive Plan ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 88 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.2.2+ ​ Form of Stock Option Agreement under the 2017 Employee, Director and Consultant Equity Incentive Plan ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 10.2.3+ ​ Form of Restricted Stock Agreement under the 2017 Employee, Director and Consultant Equity Incentive Plan ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 10.2.4+ ​ Form of Restricted Stock Unit Agreement under the 2017 Employee, Director and Consultant Equity Incentive Plan ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 10.3+ ​ Employment Agreement, dated January 1, 2015, by and between the Registrant and E. Kevin Hrusovsky ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.4+ ​ Employment Agreement, dated June 22, 2021, between the Registrant and Michael Doyle ​ ​ ​ 8-K ​ 6/28/2021 ​ 001-38319 10.5+ ​ Employment Agreement, dated May 10, 2021, between the Registrant and Dr. Masoud Toloue ​ ​ ​ 8-K ​ 5/11/2021 ​ 001-38319 10.6+ ​ Letter Agreement, dated May 31, 2019, by and between the Registrant and John Fry ​ ​ ​ 10-Q ​ 8/6/2019 ​ 001-38319 10.7+ ​ Letter Agreement, dated August 8, 2014, by and between the Registrant and Mark T. Roskey, Ph.D. ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.8+ ​ Letter Agreement, effective as February 5, 2018, by and between the Registrant and Dawn Mattoon ​ ​ ​ 10-Q ​ 5/15/2018 ​ 001-38319 10.9.1* ​ Exclusive License Agreement, dated June 18, 2007, between the Registrant and Tufts University, as amended on April 29, 2013 ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.9.2* ​ Second Amendment, dated August 22, 2017, to the Exclusive License Agreement between the Registrant and Tufts University ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 89 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.9.3 @ Third Amendment, dated September 25, 2020, to the Exclusive License Agreement between the Registrant and Tufts University ​ ​ ​ 10-Q ​ 11/6/2020 ​ 001-38319 10.10.1* ​ Supply and Manufacturing Agreement, dated September 14, 2011, between the Registrant and STRATEC Biomedical AG ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.10.2 ​ First Amendment to Supply and Manufacturing Agreement, dated October 17, 2013, between the Registrant and STRATEC Biomedical AG ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.11.1* ​ STRATEC Development Services and Equity Participation Agreement, dated August 15, 2011, between the Registrant and STRATEC Biomedical Systems AG ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.11.2* ​ First Amendment to STRATEC Development Services and Equity Participation Agreement and Second Amendment to Supply and Manufacturing Agreement, dated November 18, 2016, between the Registrant and STRATEC Biomedical AG ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.12* ​ Manufacturing Services Agreement, dated November 23, 2016, between the Registrant and Paramit Corporation ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.13+ ​ Form of Indemnification Agreement ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 10.14 ​ Lease Agreement by and between SSI 900 Middlesex MA LP and the Registrant, dated October 2, 2018. ​ ​ ​ 8-K ​ 10/5/2018 ​ 001-38319 10.15 ​ Lease Agreement by and between the Registrant and XChange Owner LLC, dated January 28, 2022 . ​ ​ ​ 8-K ​ 1/31/2022 ​ 001-38319 90 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.16 @ Non-Exclusive License Agreement, dated September 29, 2020, by and between Abbott Laboratories and the Registrant. ​ ​ ​ 8-K ​ 10/5/2020 ​ 001-38319 10.17+ ​ Separation Agreement dated November 11, 2021 by and between the Registrant and William Geist. ​ ​ ​ 8-K ​ 11/12/2021 ​ 001-38319 10.18+ ​ Amended and Restated 2018 Non-Employee Director Compensation Policy ​ X ​ ​ ​ ​ ​ ​ 21.1 ​ Subsidiaries of Registrant ​ ​ 10-K ​ 3/5/2021 ​ 001-38319 23.1 ​ Consent of Ernst & Young LLP ​ X ​ ​ ​ ​ ​ ​ 31.1 ​ Certification of the Principal Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 ​ X ​ ​ ​ ​ ​ ​ 31.2 ​ Certification of the Principal Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 ​ X ​ ​ ​ ​ ​ ​ 32.1 ​ Certifications of the Chief Executive Officer and Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. ​ X ​ ​ ​ ​ ​ ​ 101.INS ​ Inline XBRL Instance Document. ​ X ​ ​ ​ ​ ​ ​ 101.SCH ​ Inline XBRL Taxonomy Extension Schema Document. ​ X ​ ​ ​ ​ ​ ​ 101.CAL ​ Inline XBRL Taxonomy Extension Calculation Linkbase Document. ​ X ​ ​ ​ ​ ​ ​ 101.DEF ​ Inline XBRL Taxonomy Extension Definition. ​ X ​ ​ ​ ​ ​ ​ 101.LAB ​ Inline XBRL Taxonomy Extension Label Linkbase Document. ​ X ​ ​ ​ ​ ​ ​ 101.PRE ​ Inline XBRL Taxonomy Presentation Linkbase Document. ​ X ​ ​ ​ ​ ​ ​ 104 ​ Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101) ​ ​ ​ ​ ​ ​ ​ ​ 91 Table of Contents + Management contract or compensatory plan or arrangement. * Confidential treatment has been granted for portions of this Exhibit. Redacted portions have been filed separately with the SEC. @ Certain confidential portions of this exhibit have been omitted and replaced with “[***]”. Such identified information has been excluded from this exhibit because it is (i) not material and (ii) would likely cause competitive harm to the company if disclosed. Item 16. FORM 10-K SUMMARY Not applicable. ​ 92 Table of Contents SIGNATURES Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. QUANTERIX CORPORATION ​ Date: March 1, 2022 By: /s/ E. KEVIN HRUSOVSKY ​ ​ E. Kevin Hrusovsky ​ ​ Chairman and Chief Executive Officer ​ Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. ​ Signature Title Date ​ ​ ​ ​ ​ /s/ E. KEVIN HRUSOVSKY ​ Chairman and Chief Executive Officer and Director (principal executive officer) ​ March 1, 2022 E. Kevin Hrusovsky ​ ​ ​ ​ ​ /s/ MICHAEL A. DOYLE ​ Chief Financial Officer ​ March 1, 2022 Michael A. Doyle (principal financial officer and principal accounting officer) ​ ​ ​ ​ ​ /s/ KEITH L. CRANDELL ​ Director ​ March 1, 2022 Keith L. Crandell ​ ​ ​ ​ ​ /s/ SARAH E. HLAVINKA ​ Director ​ March 1, 2022 Sarah E. Hlavinka ​ ​ ​ ​ ​ /s/ MARTIN D. MADAUS, PH.D. ​ Director ​ March 1, 2022 Martin D. Madaus, Ph. D. ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ PAUL M. MEISTER ​ Director ​ March 1, 2022 Paul M. Meister ​ ​ ​ ​ ​ /s/ LAURIE J. OLSON ​ Director ​ March 1, 2022 Laurie J. Olson ​ ​ ​ ​ ​ /s/ DAVID R. WALT, PH.D. ​ Director ​ March 1, 2022 David R. Walt, Ph.D. ​ ​ ​ 93 Table of Contents INDEX TO CONSOLIDATED FINANCIAL STATEMENTS QUANTERIX CORPORATION Years ended December 31, 2021, 2020, and 2019 ​ ​ ​ Page Report of Independent Registered Public Accounting Firm (PCAOB ID: 42 ) F-2 Consolidated Balance Sheets F-4 Consolidated Statements of Operations F-5 Consolidated Statements of Comprehensive Loss F-6 Consolidated Statements of Cash Flows F-7 Consolidated Statements of Stockholders’ Equity F-8 Notes to Consolidated Financial Statements F-9 ​ ​ ​ F-1 ​ Table of Contents REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM To the Shareholders and the Board of Directors of Quanterix Corporation Opinion on the Financial Statements We have audited the accompanying consolidated balance sheets of Quanterix Corporation (the Company) as of December 31, 2021 and 2020, the related consolidated statements of operations, comprehensive loss, cash flows and stockholders' equity for each of the three years in the period ended December 31, 2021, and the related notes and financial statement schedule listed in the Index at Item 15(2) (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2021 and 2020, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2021, in conformity with U.S. generally accepted accounting principles. We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2021, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated March 1, 2022 expressed an unqualified opinion thereon. Basis for Opinion These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion. Critical Audit Matter The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the account or disclosure to which it relates. ​ ​ Excess Inventory Description of the Matter As discussed in Note 2 to the consolidated financial statements, the Company analyzes its inventory levels at each reporting date to identify inventory that is in excess of expected future demand. In the event that the Company identifies excess inventory, the Company recognizes a reduction in the carrying value of inventory. Auditing management’s valuation of inventory involved judgement in evaluating management’s analysis and significant assumptions related to projections of future demand which is dependent on market factors. F-2 ​ Table of Contents How We Addressed the Matter in Our Audit To audit the Company’s valuation of inventory, we performed audit procedures that included, among others, performing inquiries of management and testing the completeness and accuracy of the underlying data used in the estimation of future demand. To evaluate the Company’s estimate of future demand, we independently assessed the sensitivity and impact of reasonably possible changes in forecasted demand and the impact on the Company’s calculation of excess inventory. We also evaluated management's ability to accurately forecast demand by comparing actual demand to management's prior estimates. /s/ Ernst & Young LLP We have served as the Company’s auditor since 2008. Boston, Massachusetts March 1, 2022 ​ ​ ​ F-3 ​ Table of Contents Quanterix Corporation Consolidated Balance Sheets (amounts in thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 December 31, 2020 Assets ​ ​ ​ ​ ​ Current assets: ​ ​ ​ Cash and cash equivalents $ 396,465 ​ $ 181,584 Accounts receivable (less allowance for credit losses of $ 419 and $ 370 as of December 31, 2021 and December 31, 2020, respectively; including $ 200 and $ 172 due from related parties as of December 31, 2021 and December 31, 2020, respectively) 23,786 ​ 17,184 Inventory 22,190 ​ 14,856 Prepaid expenses and other current assets 6,514 ​ 5,981 Total current assets ​ 448,955 ​ 219,605 Restricted cash 2,577 ​ 1,000 Property and equipment, net 17,960 ​ 13,912 Intangible assets, net 10,534 ​ 13,716 Goodwill 9,632 ​ 10,460 Right-of-use assets ​ 11,491 ​ ​ 11,995 Other non-current assets 378 ​ 357 Total assets $ 501,527 ​ $ 271,045 Liabilities and stockholders’ equity ​ Current liabilities: ​ Accounts payable (including $ 42 and $ 14 to related parties as of December 31, 2021 and December 31, 2020, respectively) $ 9,209 ​ $ 6,799 Accrued compensation and benefits 13,252 ​ 10,777 Other accrued expenses (including $ 0 and $ 1,377 to related parties as of December 31, 2021 and December 31, 2020, respectively) 6,486 ​ 4,845 Deferred revenue (including $ 54 and $ 90 with related parties as of December 31, 2021 and December 31, 2020, respectively) 6,361 ​ 5,421 Current portion of long term debt — ​ 7,673 Short term lease liabilities ​ 1,428 ​ ​ 1,234 Other current liabilities ​ 241 ​ ​ 3,054 Total current liabilities 36,977 ​ 39,803 Deferred revenue, net of current portion 1,099 ​ 577 Long term lease liabilities ​ 20,464 ​ ​ 21,891 Deferred tax liabilities 2,035 ​ 2,649 Total liabilities 60,575 ​ 64,920 Commitments and contingencies (Note 9) ​ ​ ​ ​ ​ Stockholders’ equity: ​ Common stock, $ 0.001 par value: ​ ​ ​ Authorized— 120,000,000 shares as of December 31, 2021 and December 31, 2020; issued and outstanding — 36,768,035 and 31,796,544 shares as of December 31, 2021 and December 31, 2020, respectively 37 ​ 32 Additional paid-in capital 745,936 ​ 451,433 Accumulated other comprehensive income ​ 441 ​ ​ 2,434 Accumulated deficit ( 305,462 ) ​ ( 247,774 ) Total stockholders’ equity 440,952 ​ 206,125 Total liabilities and stockholders’ equity $ 501,527 ​ $ 271,045 ​ ​ See accompanying notes. ​ F-4 ​ Table of Contents Quanterix Corporation Consolidated Statements of Operations (amounts in thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended ​ ​ December 31, ​ 2021 2020 2019 Product revenue (including related party activity of $ 505 , $ 580 , and $ 720 for the years ended December 31, 2021, 2020, and 2019, respectively) $ 81,062 ​ $ 44,017 ​ $ 40,491 Service and other revenue (including related party activity of $ 114 , $ 202 , and $ 118 for the years ended December 31, 2021, 2020, and 2019, respectively) 23,629 ​ 24,129 ​ 16,059 Collaboration revenue 648 ​ 11,809 ​ 184 Grant revenue ​ 5,217 ​ ​ 6,422 ​ ​ — Total revenue 110,556 ​ 86,377 ​ 56,734 Costs of goods sold: ​ ​ Cost of product revenue (including related party activity of $ 1,936 , $ 205 , and $ 234 for the years ended December 31, 2021, 2020, and 2019, respectively) 34,149 ​ 25,950 ​ 20,900 Cost of service and other revenue (including related party activity of $ 74 , $ 52 , and $ 0 for the years ended December 31, 2021, 2020, and 2019, respectively) 14,679 ​ 11,245 ​ 8,998 Cost of collaboration and license revenue (including related party activity of $ 0 , $ 1,000 , and $ 0 for the years ended December 31, 2021, 2020, and 2019, respectively) ​ — ​ ​ 1,000 ​ ​ — Total costs of goods sold, services, and licenses 48,828 ​ 38,195 ​ 29,898 Gross profit ​ 61,728 ​ ​ 48,182 ​ ​ 26,836 Operating expenses: ​ ​ Research and development (including related party activity of $ 565 , $ 235 , and $ 152 for the years ended December 31, 2021, 2020, and 2019, respectively) 27,978 ​ 20,174 ​ 16,190 Selling, general and administrative (including related party activity of $ 89 , $ 37 , and $ 180 for the years ended December 31, 2021, 2020, and 2019, respectively) 92,336 ​ 59,592 ​ 52,246 Total operating expenses 120,314 ​ 79,766 ​ 68,436 Loss from operations ( 58,586 ) ​ ( 31,584 ) ​ ( 41,600 ) Interest (expense) income, net ( 403 ) ​ ( 273 ) ​ 627 Other income (expense), net 1,265 ​ ( 49 ) ​ ( 10 ) Loss before income taxes ​ ( 57,724 ) ​ ​ ( 31,906 ) ​ ​ ( 40,983 ) Income tax benefit ​ 36 ​ ​ 376 ​ ​ 187 Net loss $ ( 57,688 ) ​ $ ( 31,530 ) ​ $ ( 40,796 ) Net loss per share, basic and diluted $ ( 1.60 ) ​ $ ( 1.07 ) ​ $ ( 1.63 ) Weighted-average common shares outstanding, basic and diluted 35,997,473 ​ 29,589,132 ​ 25,090,708 ​ See accompanying notes. ​ F-5 ​ Table of Contents ​ ​ ​ Quanterix Corporation Consolidated Statements of Comprehensive Loss (amounts in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 ​ 2019 Net loss $ ( 57,688 ) ​ $ ( 31,530 ) ​ $ ( 40,796 ) Other comprehensive (loss) income: ​ ​ ​ ​ ​ ​ ​ ​ Cumulative translation adjustment ​ ( 1,993 ) ​ ​ 2,587 ​ ​ ( 153 ) Total other comprehensive (loss) income ​ ( 1,993 ) ​ ​ 2,587 ​ ​ ( 153 ) Comprehensive loss $ ( 59,681 ) ​ $ ( 28,943 ) ​ $ ( 40,949 ) ​ See accompanying notes. ​ ​ ​ ​ ​ F-6 ​ Table of Contents Quanterix Corporation Consolidated Statements of C as h Flows (amounts in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2021 2020 2019 Operating activities ​ ​ Net loss $ ( 57,688 ) ​ $ ( 31,530 ) ​ $ ( 40,796 ) Adjustments to reconcile net loss to net cash used in operating activities: ​ ​ ​ Depreciation and amortization expense 4,851 ​ 4,312 ​ 3,009 Inventory step-up amortization ​ 275 ​ ​ 722 ​ ​ 611 Credit loss expense on accounts receivable ​ 213 ​ ​ 493 ​ ​ 160 Reduction in the carrying amounts of right-of-use assets ​ 499 ​ ​ 245 ​ ​ — Stock-based compensation expense 15,975 ​ 10,099 ​ 6,388 Non-cash interest expense 65 ​ 86 ​ 89 Loss on disposal of fixed assets 89 ​ 171 ​ 140 Changes in operating assets and liabilities: ​ ​ ​ ​ Accounts receivable ( 6,853 ) ​ ( 6,733 ) ​ ( 3,525 ) Prepaid expenses and other assets ( 393 ) ​ ( 3,927 ) ​ 289 Inventory ( 8,090 ) ​ ( 5,119 ) ​ ( 3,447 ) Other non-current assets ( 2 ) ​ 198 ​ ( 21 ) Accounts payable 2,414 ​ 649 ​ 621 Accrued compensation and benefits, other accrued expenses and other current liabilities 1,061 ​ 6,219 ​ 822 Contract acquisition costs ​ ( 192 ) ​ ​ 87 ​ ​ 336 Operating lease liabilities ​ ( 1,230 ) ​ ​ 316 ​ ​ — Other non-current liabilities ​ ( 363 ) ​ ​ ( 488 ) ​ ​ 9,845 Deferred revenue 1,462 ​ 835 ​ ( 708 ) Net cash used in operating activities ​ ( 47,907 ) ​ ​ ( 23,365 ) ​ ( 26,187 ) Investing activities ​ ​ ​ Purchases of property and equipment ( 13,616 ) ​ ( 3,930 ) ​ ( 10,847 ) Acquisitions, net of cash acquired ​ — ​ ​ — ​ ​ ( 14,529 ) Proceeds from RADx grant on assets purchased ​ 7,278 ​ ​ 3,304 ​ ​ — Net cash used in investing activities ​ ( 6,338 ) ​ ​ ( 626 ) ​ ​ ( 25,376 ) Financing activities ​ ​ — ​ — Proceeds from stock options exercised 7,750 ​ 4,019 ​ 2,820 Sale of common stock in at-the-market offering, net ​ — ​ ​ — ​ ​ 48,019 Sale of common stock in underwritten public offering, net ​ 269,718 ​ ​ 91,404 ​ ​ 64,529 Proceeds from ESPP purchase 1,065 ​ 888 ​ 879 Payments on notes payable ( 7,738 ) ​ ( 75 ) ​ ( 50 ) Net cash provided by financing activities ​ 270,795 ​ ​ 96,236 ​ ​ 116,197 Net increase in cash and cash equivalents 216,550 ​ 72,245 ​ 64,634 Effect of foreign currency exchange rate on cash ​ ( 92 ) ​ ​ 158 ​ ​ 118 Cash, restricted cash, and cash equivalents at beginning of period 182,584 ​ 110,181 ​ 45,429 Cash, restricted cash, and cash equivalents at end of period $ 399,042 ​ $ 182,584 ​ $ 110,181 Supplemental cash flow information ​ ​ Cash paid for interest $ 389 ​ $ 625 ​ $ 656 Purchases of property and equipment included in accounts payable and other accrued expenses $ 229 ​ $ 1,029 ​ $ 164 Purchase of property and equipment included in other non-current liabilities $ — ​ $ — ​ $ 7,572 Common stock issued in connection with the acquisition of UmanDiagnostics AB $ — ​ $ — ​ $ 5,468 Reconciliation of cash, cash equivalents, and restricted cash: ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents $ 396,465 ​ $ 181,584 ​ $ 109,155 Restricted cash $ 2,577 ​ $ 1,000 ​ $ 1,026 Total cash, cash equivalents, and restricted cash $ 399,042 ​ $ 182,584 ​ $ 110,181 ​ ​ See accompanying notes. ​ ​ F-7 Table of Contents Quanterix Corporation Consolidated Statements of Stockholders’ Equity ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Common ​ Common ​ Additional ​ other ​ ​ ​ ​ ​ Total ​ stock ​ stock ​ paid-in ​ comprehensive ​ ​ Accumulated ​ ​ stockholders’ ​ shares ​ value ​ capital ​ income (loss) ​ ​ deficit ​ ​ equity Balance at December 31, 2018 22,369,036 ​ $ 22 ​ $ 216,931 ​ $ — ​ $ ( 175,888 ) ​ $ 41,065 Cumulative effect of adoption of Accounting Standards Codification Topic 606 — ​ — ​ — ​ — ​ ​ 440 ​ ​ 440 Exercise of common stock warrants 45,690 ​ — ​ — ​ — ​ ​ — ​ ​ — Exercise of common stock options and vesting of restricted stock 550,734 ​ — ​ 2,820 ​ — ​ ​ — ​ ​ 2,820 Sale of common stock in "at-the-market" offering, net 2,186,163 ​ 2 ​ 48,017 ​ — ​ ​ — ​ ​ 48,019 Sale of common stock in underwritten public offering, net 2,732,673 ​ ​ 3 ​ ​ 64,526 ​ ​ — ​ ​ — ​ ​ 64,529 Issuance of shares for the acquisition of UmanDiagnostics AB 191,152 ​ ​ 1 ​ ​ 5,467 ​ ​ — ​ ​ — ​ ​ 5,468 Stock-based compensation expense — ​ ​ — ​ ​ 6,388 ​ ​ — ​ ​ — ​ ​ 6,388 Employee stock purchase plan 36,753 ​ ​ — ​ ​ 878 ​ ​ — ​ ​ — ​ ​ 878 Accumulated other comprehensive income — ​ ​ — ​ ​ — ​ ​ ( 153 ) ​ ​ — ​ ​ ( 153 ) Net loss — ​ — ​ — ​ — ​ ​ ( 40,796 ) ​ ​ ( 40,796 ) Balance at December 31, 2019 28,112,201 ​ $ 28 ​ $ 345,027 ​ $ ( 153 ) ​ $ ( 216,244 ) ​ $ 128,658 Exercise of common stock options and vesting of restricted stock 589,723 ​ ​ 1 ​ ​ 4,018 ​ ​ — ​ ​ — ​ ​ 4,019 Sale of common stock in underwritten public offering, net 3,048,774 ​ ​ 3 ​ ​ 91,401 ​ ​ — ​ ​ — ​ ​ 91,404 ESPP stock purchase 45,846 ​ ​ — ​ ​ 888 ​ ​ — ​ ​ — ​ ​ 888 Stock-based compensation expense — ​ ​ — ​ ​ 10,099 ​ ​ — ​ ​ — ​ ​ 10,099 Cumulative translation adjustment — ​ ​ — ​ ​ — ​ ​ 2,587 ​ ​ — ​ ​ 2,587 Net loss — ​ ​ — ​ ​ — ​ ​ — ​ ​ ( 31,530 ) ​ ​ ( 31,530 ) Balance at December 31, 2020 31,796,544 ​ $ 32 ​ $ 451,433 ​ $ 2,434 ​ $ ( 247,774 ) ​ $ 206,125 Exercise of common stock warrants 7,347 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Exercise of common stock options and vesting of restricted stock 823,796 ​ ​ 1 ​ ​ 7,749 ​ ​ — ​ ​ — ​ ​ 7,750 Issuance of common stock 4,169 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sale of common stock in underwritten public offering, net 4,107,142 ​ ​ 4 ​ ​ 269,714 ​ ​ — ​ ​ — ​ ​ 269,718 ESPP stock purchase 29,037 ​ ​ — ​ ​ 1,065 ​ ​ — ​ ​ — ​ ​ 1,065 Stock-based compensation expense — ​ ​ — ​ ​ 15,975 ​ ​ — ​ ​ — ​ ​ 15,975 Cumulative translation adjustment — ​ ​ — ​ ​ — ​ ​ ( 1,993 ) ​ ​ — ​ ​ ( 1,993 ) Net loss — ​ ​ — ​ ​ — ​ ​ — ​ ​ ( 57,688 ) ​ ​ ( 57,688 ) Balance at December 31, 2021 36,768,035 ​ $ 37 ​ $ 745,936 ​ $ 441 ​ $ ( 305,462 ) ​ $ 440,952 ​ See accompanying notes. ​ ​ F-8 Table of Contents Quanterix Corporation Notes to Consolidated Financial Statements 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, but 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 UmanDiagnostics AB (Uman), a Swedish company located in Umeå, Sweden, in August 2019. The acquisition closed with respect to 95 % of the outstanding shares of capital stock of Uman on July 1, 2019 and with respect to the remaining 5 % of the outstanding shares of capital stock of Uman on August 1, 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. “At-the-market offering” On March 19, 2019, the Company entered into a Sales Agreement (the Sales Agreement) with Cowen and Company, LLC (Cowen) with respect to an “at-the-market” offering program under which the Company could offer and sell, from time to time at its sole discretion, shares of its common stock, par value $ 0.001 per share, having an aggregate offering price of up to $ 50.0 million through Cowen as its sales agent. On June 5, 2019, the Company issued approximately 2.2 million shares of common stock at an average stock price of $ 22.73 per share pursuant to the terms of the Sales Agreement. The “at-the-market” offering resulted in gross proceeds of $ 49.7 million. The Company incurred $ 1.7 million in issuance costs associated with the “at-the-market” offering, resulting in net proceeds to the Company of $ 48.0 million. On August 6, 2020, the Company delivered written notice to Cowen to terminate the Sales Agreement, which termination the parties agreed to make immediately effective. F-9 Table of Contents Underwritten public offering On August 8, 2019, the Company entered into an underwriting agreement with J.P. Morgan Securities LLC (J.P. Morgan) and SVB Securities LLC (f/k/a SVB Leerink) (Leerink), as representatives of the several underwriters, relating to an underwritten public offering of approximately 2.7 million shares of the Company’s common stock, par value $ 0.001 per share. The underwritten public offering resulted in gross proceeds of $ 69.0 million. The Company incurred $ 4.5 million in issuance costs associated with the underwritten public offering, resulting in net proceeds to the Company of $ 64.5 million. On August 6, 2020, the Company entered into an underwriting agreement with Leerink and Cowen and Company, LLC (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 (Goldman Sachs), Leerink, 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. Liquidity The Company has recognized annual losses from operations since inception and has an accumulated deficit of $ 305.5 million at December 31, 2021 and the Company incurred a net loss of $ 57.7 million, $31.5 million, and $40.8 million for the years ended December 31, 2021, 2020, and 2019, respectively. At December 31, 2021, the Company had $ 396.5 million of unrestricted cash and cash equivalents. The Company expects the current cash balance will be sufficient to fund operations for a period of at least one year from the date the consolidated financial statements are issued. There can be no assurances, however, that no additional funding will be required or that additional funding will be available on terms acceptable to the Company, or at all. ​ 2. Significant accounting policies Principles of consolidation The 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, and valuation of inventory. Actual results could differ from those estimates. Reclassifications Certain amounts in the prior years’ consolidated financial statements have been reclassified to conform to the current year’s presentation. F-10 Table of Contents Segment information Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision-maker, the Company’s Chief Executive Officer, in deciding how to allocate resources and assess performance. The Company and the Company's chief operating decision-maker reviews the Company's operations and manages its business as a single operating segment. 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. The Company adopted Accounting Standards Codification (ASC) Topic 606 Revenue from Contracts with Customers (ASC 606), on January 1, 2019, using the modified retrospective method for all contracts not completed as of the date of adoption. The reported results for 2021, 2020, and 2019 reflect the application of ASC 606 guidance. The Company recorded an adjustment to the accumulated deficit of $ 0.4 million as of January 1, 2019 for the cumulative effect primarily related to the deferral of sales commissions. In accordance with the reporting requirements of ASC 606, the disclosure of the impact on the Company’s consolidated statement of operations, as a result of adopting the provisions of ASC 606, was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, 2019 ​ ​ ​ ​ ​ Under ASC ​ Under ASC 606 Adjustment 605 Product revenue $ 40,491 $ 55 $ 40,546 Service revenue 16,059 ​ 273 ​ 16,332 Costs of goods sold and services 29,898 ​ 1 ​ 29,899 Gross profit 26,836 ​ 327 ​ 27,163 Selling general and administrative expenses 52,246 ​ 27 ​ 52,273 Net loss $ ( 40,796 ) $ 300 $ ( 40,496 ) 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). F-11 Table of Contents 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 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. The Company has recognized revenues from sales- or usage based royalties related to the Company’s licensing technology and intellectual property. 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- or usage-based royalty will be recognized in the period the underlying transaction occurs. The Company has recorded sales- or usage-based royalty revenue for the years ended December 31, 2021, 2020, and 2019 related to the intellectual property licensed by Uman. The Company recognizes revenues from sales- or usage based royalty revenue at the later of when the sales or usage occurs; and the satisfaction or partial satisfaction of the performance obligation to which the royalty has been allocated. Payment terms The Company’s payment terms vary by the type and location of customer and the products or services offered. Payment from customers is generally required in a term ranging from 30 to 45 days from date of shipment or satisfaction of the performance obligation with no discounts for early payment. Occasionally the Company provides extended payment terms or financing arrangements to customers. F-12 Table of Contents 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 based on their location by revenue type: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2021 (in thousands) ​ NA EMEA Asia Pacific Total Product revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments ​ $ 12,138 ​ $ 8,178 ​ $ 5,657 ​ $ 25,973 Consumable and other products ​ ​ 34,997 ​ ​ 16,122 ​ ​ 3,970 ​ ​ 55,089 Total ​ $ 47,135 $ 24,300 $ 9,627 $ 81,062 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties ​ $ 4,334 ​ $ 2,039 ​ $ 255 ​ $ 6,628 Research services ​ ​ 12,101 ​ ​ 2,600 ​ ​ 124 ​ 14,825 Other services ​ ​ 1,372 ​ ​ 695 ​ ​ 109 ​ ​ 2,176 Total ​ $ 17,807 ​ $ 5,334 ​ $ 488 ​ $ 23,629 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 360 ​ $ 288 ​ $ — ​ $ 648 Total ​ $ 360 $ 288 $ — $ 648 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2020 (in thousands) ​ NA EMEA Asia Pacific Total Product revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments ​ $ 8,680 $ 4,332 $ 3,594 $ 16,606 Consumable and other products ​ ​ 14,305 ​ 10,854 ​ 2,252 ​ 27,411 Total ​ $ 22,985 $ 15,186 $ 5,846 $ 44,017 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties ​ $ 3,171 $ 1,543 $ 207 $ 4,921 Research services ​ ​ 15,011 ​ 2,225 ​ 737 ​ 17,973 Other services ​ ​ 700 ​ 435 ​ 100 ​ 1,235 Total ​ $ 18,882 ​ $ 4,203 ​ $ 1,044 ​ $ 24,129 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 11,685 ​ $ 124 ​ $ — ​ $ 11,809 Total ​ $ 11,685 $ 124 $ — $ 11,809 F-13 Table of Contents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2019 (in thousands) ​ NA EMEA Asia Pacific Total Product revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments ​ $ 6,250 $ 5,243 $ 3,393 $ 14,886 Consumable and other products ​ ​ 14,148 ​ 9,674 ​ 1,783 ​ 25,605 Total ​ $ 20,398 $ 14,917 $ 5,176 $ 40,491 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties ​ $ 3,139 $ 1,323 $ 171 $ 4,633 Research services ​ ​ 8,845 ​ 704 ​ 456 ​ 10,005 Other services ​ ​ 825 ​ 565 ​ 31 ​ 1,421 Total ​ $ 12,809 ​ $ 2,592 ​ $ 658 ​ $ 16,059 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 167 ​ $ 17 ​ $ — ​ $ 184 Total ​ $ 167 $ 17 $ — $ 184 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. The aggregate amount of transaction price that is allocated to performance obligations that have not yet been satisfied or that are partially satisfied as of December 31, 2021 is $ 7.5 million. Of the performance obligations not yet satisfied or that are partially satisfied, $ 6.4 million is expected to be recognized as revenue in the next 12 months , with the remainder to be recognized within the 24 months thereafter. The $ 7.5 million principally consists of amounts billed for undelivered services related to initial and extended service-type warranties and research services, as well as $ 0.5 million related to undelivered licenses of intellectual property for a diagnostics company. Changes in deferred revenue from contracts with customers were as follows (in thousands): ​ ​ ​ ​ ​ Year Ended December 31, 2021 Balance at December 31, 2020 $ 5,998 Deferral of revenue ​ 8,090 Recognition of deferred revenue ​ ( 6,628 ) Balance at December 31, 2021 $ 7,460 ​ 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 changes in the balance of costs to obtain a contract are as follows (in thousands): F-14 Table of Contents ​ ​ ​ ​ ​ ​ Year Ended December 31, 2021 Balance at December 31, 2020 $ 248 Deferral of costs to obtain a contract ​ 905 Recognition of costs to obtain a contract ​ ( 713 ) Balance at December 31, 2021 $ 440 ​ The Company has classified the balance of capitalized costs to obtain a contract as a component of prepaid expenses and other current assets as of December 31, 2021 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 will exclude from its transaction price any amounts collected from customers related to sales and other similar taxes. The Company has elected to account for 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. 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. 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 for the years ended December 31, 2021, 2020 and 2019. 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 (IAS 20). 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 F-15 Table of Contents 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 WP2 with the NIH under its RADx program. The contract, 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. Contract funding was subject to achievement of these pre-defined milestones and the contract period ran through September 2021, with one milestone extended to March 31, 2022. As of December 31, 2021, the Company had received $ 17.7 million out of the full $ 18.2 million under WP2 . During the year ended December 31, 2021, the Company recognized $ 5.2 million in grant revenue and incurred $ 3.4 million in research and development expense related to WP2. During the year ended December 31, 2020, the Company recognized $ 4.4 million in grant revenue and incurred $ 2.6 million in research and development expense related to WP2. The following table summarizes the cumulative activity under WP2 as of December 31, 2021 and December 31, 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ December 31, 2020 Total grant revenue from research and development activities $ 9,576 ​ $ 4,362 Total proceeds used for assets ​ 8,104 ​ ​ 826 Total deferred proceeds for assets ​ — ​ ​ 2,478 Total deferred grant revenue ​ — ​ ​ 304 Total recognized $ 17,680 ​ $ 7,970 ​ ​ ​ ​ ​ ​ Total recognized $ 17,680 ​ $ 7,970 Total amount accrued ​ — ​ ​ ( 2,968 ) Total cash received $ 17,680 ​ $ 5,002 ​ ​ ​ ​ ​ ​ Total proceeds received $ 17,680 ​ $ 5,002 Total proceeds reasonably assured ​ 520 ​ ​ 13,198 Total WP2 grant amount $ 18,200 ​ $ 18,200 ​ 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 recognized, 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 acquired tangible and intangible assets, net of liabilities recognized, 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. 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 F-16 Table of Contents 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. Cost of revenue Cost of product revenue consists of raw materials, parts costs and associated freight, shipping and handling costs, contract manufacturer costs, personnel costs, yield loss, in-license payments and royalties, stock-based compensation, other direct costs and overhead. Cost of service and other revenue consists of personnel, facility costs associated with operating the Accelerator Laboratory on behalf of the customers, costs related to instrument maintenance and servicing equipment at customer sites, other direct and overhead. Cost of license revenue consists of license fees that are the direct results of cash payments received related to license agreements. Research and development expenses Research and development expenses, including personnel costs, allocated facility costs, lab supplies, outside services, contract laboratory costs are charged to research and development expense as incurred. The Company accounts for nonrefundable advance payments for goods and services that will be used in future research and development activities as expense when the service has been performed or when the goods have been received. Expenses incurred related to grant funded activities are recorded in research and development expense. Selling, general, and administrative expenses Selling, general, and administrative expenses are primarily composed of compensation and benefits associated with sales and marketing, finance, human resources, and other administrative personnel, outside marketing, advertising, allocated facilities costs, legal expenses, and other general and administrative costs. Net loss per share Basic net loss per common share attributable to common stockholders is calculated by dividing the loss attributable to common stockholders by the weighted-average number of common shares. For purposes of the diluted net loss per share calculations, unvested restricted common stock, restricted stock units, common stock options, and warrants are considered to be potentially dilutive securities, but are excluded from the 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): ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2021 2020 2019 Unvested restricted common stock and restricted stock units 531,473 518,387 409,929 Outstanding stock options 2,304,543 2,494,045 2,507,062 Outstanding common stock warrants — 10,000 10,000 ​ F-17 Table of Contents Cash and cash equivalents Cash and cash equivalents consist of cash deposits and short-term, highly liquid investments that are readily convertible into cash, with original maturities of three months or less. Cash equivalents are carried at fair value based on quoted prices for identical assets. Cash and cash equivalents consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ ​ December 31, ​ 2021 2020 Cash ​ $ 64,372 ​ $ 19,535 Money market funds invested in U.S. Treasury obligations ​ 332,093 ​ 162,049 Total cash and cash equivalents ​ $ 396,465 ​ $ 181,584 ​ Restricted cash and deposits 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 additional space in Bedford, 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 December 31, 2021. 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 customers’ 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. Inventory Inventory is stated at the lower of cost or market on a first-in, first-out (FIFO) basis. The Company analyzes its inventory levels on each reporting date and writes down inventory that is expected to expire prior to being sold and inventory in excess of expected sales requirements. In the event that the Company identifies these conditions exist in its inventory, the carrying value is reduced to its estimated net realizable value. Property and equipment Property and equipment, including leasehold improvements, are stated at cost and are depreciated, or amortized in the case of leasehold improvements, over their estimated useful lives using the straight-line method. Expenditures for maintenance and repairs are charged to expense as incurred, whereas major betterments are capitalized as additions to property and equipment. The Company reviews its property and equipment whenever events or changes in circumstances indicate that the carrying value of certain assets might not be recoverable and recognizes an impairment F-18 Table of Contents loss when it is probable that an asset’s realizable value is less than the carrying value. To date, no such impairment losses have been recorded. Depreciation is calculated based upon the following estimated useful lives of the assets: ​ ​ ​ ​ Laboratory and manufacturing equipment Five years Computers and software Three years Office furniture and equipment Seven years Leasehold improvements Shorter of the useful life of the asset or the remaining term of the lease ​ Leases The Company accounts for leases in accordance with ASC Topic 842, Leases (ASC 842), which was adopted on January 1, 2020, using the optional transition method allowing entities to recognize a cumulative effect adjustment to the opening balance sheet without restating comparative prior periods presented. At adoption the Company elected the package of practical expedients which was applied consistently to all of its leases at the transition date: i) the Company did not reassess whether any expired or existing contracts are or contain leases; ii) the Company did not reassess the lease classification for any expired or existing leases (that is, all existing leases that were classified as operating leases in accordance with ASC 840, Leases (ASC 840), are classified as operating leases); and iii) the Company did not reassess initial direct costs for any existing leases. ASC 842 requires a lessee to recognize assets and liabilities on the balance sheet for most leases and changes many key definitions, including the definition of a lease. Lessees are differentiated between finance leases and operating leases, and classification impacts expense recognition. At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the facts and circumstances present in the arrangement. Leases with a term greater than one year are recognized on the balance sheet as right-of-use (ROU) assets and short-term and long-term lease liabilities, as applicable. The Company does not recognize leases on the balance sheet with a term of twelve months or less. The Company’s leases consist of office and lab space and office equipment. All of the Company’s leases are classified as operating, and options to renew a lease are only included in the lease term to the extent those options are reasonably certain to be exercised. Additionally, the Company does not separate lease and non-lease components for all leases. Operating lease liabilities and their corresponding ROU assets are initially recorded based on the present value of lease payments over the expected remaining lease term. The rate implicit in lease contracts is typically not readily determinable and, as a result, the Company utilizes its incremental borrowing rate to discount lease payments, which reflects the fixed rate at which the Company could borrow on a collateralized basis the amount of the lease payments, for a similar term, in a similar economic environment. To estimate its incremental borrowing rate, a credit rating applicable to the Company is estimated using a synthetic credit rating analysis since the Company does not currently have a rating agency-based credit rating. Software development costs The Company develops and modifies software related to the operation of the instrument. Software development costs are expensed as incurred until the point the Company establishes technological feasibility. Based on the Company’s product development process, technological feasibility is established upon the completion of a working model. The Company does not incur material costs between the completion of the working model and the point at which the product is ready for release. Therefore, software development costs are charged to the statement of operations as incurred as research and development expense. Fair value of financial instruments ASC Topic 820, Fair Value Measurement (ASC 820), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable F-19 Table of Contents inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability, and are developed based on the best information available in the circumstances. 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. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying amount reflected on the balance sheets for cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable and accrued liabilities approximated their fair values, due to the short-term nature of these instruments. The carrying value of the long-term debt approximates its fair value as the debt arrangement is based on interest rates the Company believes it could obtain for borrowings with similar terms. Fair value measurements are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs December 31, 2021 Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 332,093 $ 332,093 ​ $ — $ — ​ ​ $ 332,093 ​ $ 332,093 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ Significant ​ Significant ​ ​ ​ ​ ​ in active ​ other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs December 31, 2020 Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents $ 162,049 $ 162,049 ​ $ — $ — ​ $ 162,049 $ 162,049 ​ $ — $ — ​ Warranties The Company provides a one-year warranty and maintenance service related to its instruments and sells extended warranty contracts for additional periods. The Company defers revenue associated with these services and recognizes them on a pro-rata basis over the period of service. 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, F-20 Table of Contents 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 ASC 740 Income Taxes (ASC 740). When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. As of December 31, 2021 and 2020, the Company did not have any significant uncertain tax positions. Credit, product, and supplier concentrations and off-balance-sheet risk The Company has no significant off-balance-sheet risk, such as foreign exchange contracts, option contracts, or other hedging arrangements. Financial instruments that potentially expose the Company to concentrations of credit risk primarily consist of cash and cash equivalents and a cost method investment. The Company places its cash and cash equivalents principally in depository accounts with a bank. The Company is also subject to supply chain risks related to the outsourcing of the manufacturing of its instruments. Although there are a limited number of manufacturers for instruments of this type, the Company believes that other suppliers could provide similar products on comparable terms. A change in suppliers, however, could cause a delay in manufacturing and a possible loss of sales, which would adversely affect operating results. In addition to outsourcing the manufacturing of its instruments, the Company also purchases antibodies through a number of different suppliers. Although a disruption in service from any one of its antibody suppliers is possible, the Company believes that it would be able to find an adequate supply from alternative suppliers. Customers outside the United States represented 39 % and 29 % of the Company’s gross trade accounts receivable balance as of December 31, 2021 and 2020, respectively. As of December 31, 2021, one customer represented 18 % of the Company’s aggregate accounts receivable. As of December 31, 2020, one customer represented 19 % of the Company’s aggregate accounts receivable. During the years ended December 31, 2021 and 2019, no individual customer represented 10 % of the Company’s total revenue. During the year ended December 31, 2020, one company represented 13 % of the Company’s total revenue. Stock-based compensation The Company accounts for stock-based compensation awards in accordance with ASC 718, Compensation—Stock Compensation (ASC 718). ASC 718 requires all stock-based payments to employees including grants of employee stock options, to be recognized in the statement of operations based on their fair values. Stock-based compensation awards have historically consisted of stock options and restricted stock. Prior to the adoption of Accounting Standards Update (ASU) No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07), the measurement date for non-employee awards was generally the date the services were completed, resulting in financial reporting period adjustments to stock-based compensation during the vesting period for changes in the fair value of the awards. The Company adopted ASU 2018-07 on January 1, 2020. After the adoption of ASU 2018-07, the measurement date for non-employee awards is the date of grant without changes in the fair value of the award. Stock-based compensation costs for non-employees are recognized as expense over the vesting period on a straight-line basis. There were no material non-employee awards outstanding during the years ended December 31, 2021, 2020, and 2019. The Company recognizes forfeitures as they occur. The Company estimates the grant date fair value, and the resulting stock-based compensation expense, using the Black-Scholes option-pricing model. The grant date fair value of the stock-based awards is generally recognized on a straight-line basis over the requisite service period, which is generally the vesting period of the respective awards. F-21 Table of Contents The fair value of stock options granted to employees and non-employees is estimated on the grant date using the Black-Scholes option-pricing model, based on the assumptions noted in the following table: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2021 ​ 2020 ​ 2019 Risk-free interest rate 0.4 % - 1.3 % ​ 0.4 % - 1.7 % ​ 1.4 % - 2.6 % Expected dividend yield None ​ None ​ None Expected term (in years) 6.0 ​ 6.0 ​ 6.0 Expected volatility 49.2 % - 55.6 % ​ 43.9 % - 49.2 % ​ 33.5 % - 39.7 % Weighted-average grant date fair value $ 29.96 ​ $ 12.66 ​ $ 9.09 ​ Expected volatility was calculated based a proportional weighting of reported volatility data for a representative group of guideline publicly traded companies for which historical information was available, as well as the Company’s stock. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant, commensurate with the expected term assumption. The Company estimates the expected term of options granted to employees utilizing the simplified method which calculates the expected term of an option as the average of the time to vesting and contractual life of the options. The expected term is applied to the stock option grant group as a whole, as the Company does not expect substantially different exercise or post-vesting termination behavior among its employee population. The Company uses the simplified method due to the lack of historical exercise data and the plain nature of the stock options. The Company uses the remaining contractual term for the expected term of non-employee awards. The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay any dividends on common stock. Recent accounting pronouncements Adopted In June 2016, the Financial Accounting Standards Board (FASB) established Topic 326 , Financial Instruments — Credit Losses: Measurement of Credit Losses on Financial Instruments (ASC 326) by issuing ASU No. 2016-13 (ASU 2016-13), which amends the impairment model by requiring entities to use a forward-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 (ASU 2018-15) . 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 (ASU 2019-12), which is intended to simplify various areas related to ASC 740, Income Taxes (ASC 740). ASU 2019-12 removes certain exceptions for performing intra period tax allocations and calculating income taxes in interim periods. The guidance also simplifies the accounting for transactions that result in a step-up in the tax basis of goodwill and the effect of enacted changes in tax laws or rates in interim periods. The Company early adopted ASU 2019-12 on January 1, 2021. The adoption of ASU 2019-12 did not have a material impact on the Company’s consolidated financial statements. ​ F-22 Table of Contents 3. Inventory Inventory consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2021 2020 Raw materials ​ $ 7,892 ​ $ 5,265 Work in process ​ 4,923 ​ 3,306 Finished goods ​ 9,375 ​ 6,285 Total ​ $ 22,190 ​ $ 14,856 ​ Inventory comprises commercial instruments, assays, and the materials required to manufacture assays. 4. Property and equipment Property and equipment consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2021 2020 Laboratory and manufacturing equipment ​ $ 9,742 ​ $ 8,523 Office furniture and equipment ​ 1,617 ​ 1,556 Computers and software ​ 3,893 ​ 1,504 Leasehold improvements ​ 10,413 ​ 8,765 Total cost ​ $ 25,665 ​ $ 20,348 Less: accumulated depreciation ​ ( 7,705 ) ​ ( 6,436 ) Property and equipment, net ​ $ 17,960 ​ $ 13,912 ​ The Company incurred depreciation expense of $ 2.8 million, $ 2.2 million and $ 1.6 million for the years ended December 31, 2021 2020, and 2019, respectively. The Company has instruments included in laboratory and manufacturing equipment, which are used internally by the Company. As of December 31, 2021, the laboratory and manufacturing equipment balance includes $ 3.9 million of cost and $ 1.5 million of accumulated depreciation related to these instruments. As of December 31, 2020, the laboratory and manufacturing equipment balance includes $ 3.4 million of cost and $ 1.8 million of accumulated depreciation related to these instruments. ​ 5. Other accrued expenses Other accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2021 2020 Accrued inventory purchases $ 568 ​ $ 527 Accrued property and equipment purchases ​ 229 ​ ​ 670 Accrued royalties 1,250 ​ 1,845 Accrued professional services 2,126 ​ 797 Accrued development costs 566 ​ 323 Accrued tax liabilities ​ 430 ​ ​ 156 Accrued other 1,317 ​ 527 Total accrued expenses $ 6,486 ​ $ 4,845 ​ ​ ​ F-23 Table of Contents 6. Income taxes The following table presents the components of loss before income taxes (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2021 ​ 2020 2019 United States ​ $ ( 56,554 ) ​ $ ( 29,896 ) ​ $ ( 40,010 ) Foreign ​ ( 1,170 ) ​ ( 2,010 ) ​ ( 973 ) Total loss before income taxes ​ $ ( 57,724 ) ​ $ ( 31,906 ) ​ $ ( 40,983 ) ​ The following table summarizes income tax benefit (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2021 2020 2019 Current: ​ ​ ​ ​ ​ ​ ​ ​ United States ​ ​ ​ ​ ​ ​ ​ ​ Federal $ — $ — $ — State ​ ( 30 ) ​ ​ ( 13 ) ​ ​ ( 20 ) Foreign ​ ( 342 ) ​ ​ ( 102 ) ​ ​ ( 93 ) Total current income tax provision ​ ( 372 ) ​ ​ ( 115 ) ​ ​ ( 113 ) Deferred ​ ​ ​ ​ ​ ​ ​ ​ United States ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ 5 ​ ​ ( 8 ) ​ ​ ( 3 ) State ​ ( 6 ) ​ ​ ( 3 ) ​ ​ ( 1 ) Foreign ​ 409 ​ ​ 502 ​ ​ 304 Total deferred income tax benefit ​ 408 ​ ​ 491 ​ ​ 300 Total income tax benefit $ 36 ​ $ 376 ​ $ 187 ​ A reconciliation of the federal statutory income tax rate to the effective tax rate is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2021 2020 2019 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % Foreign tax rate differential — % 0.30 % — % State taxes, net of federal benefit 6.5 % 2.5 % 3.2 % Tax credits 2.0 % 1.6 % 2.3 % Share-based compensation 7.4 % 5.2 % 2.3 % Permanent items ( 1.8 ) % ( 0.4 ) % ( 0.9 ) % Deferred tax rate change 0.2 % 0.3 % ( 1.4 ) % Change in valuation allowance ( 34.8 ) % ( 29.7 ) % ( 24.6 ) % Other ( 0.4 ) % 0.4 % ( 1.4 ) % Effective income tax rate 0.1 % 1.2 % 0.5 % ​ The effective income tax rate of differs from the U.S. Federal statutory rate of 21.0 % primarily as a result of the valuation allowance maintained against the Company’s net deferred tax assets. During 2019, the Company acquired Uman, a Swedish entity. The Company analyzed the transaction from an income tax perspective and found that there was no tax deductible goodwill or other identifiable intangible assets related to the transaction. F-24 Table of Contents Deferred tax assets and liabilities reflect the net tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting and the amounts used for income tax purposes. Significant components of the Company’s deferred tax assets and liabilities were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Deferred tax assets: ​ ​ Net operating loss carryforwards $ 67,543 ​ $ 50,233 Tax credits 6,113 ​ 5,101 Deferred revenue ​ 1,862 ​ ​ 2,167 Amortization ​ 962 ​ ​ 1,054 Stock-based compensation 3,138 ​ 1,956 Inventory ​ 686 ​ ​ — Lease liability ​ 5,464 ​ ​ 5,703 Other deferred tax assets ​ 2,340 ​ ​ 2,533 Total deferred tax assets 88,108 ​ 68,747 Less: valuation allowances ​ ( 83,121 ) ​ ​ ( 63,609 ) Net deferred tax assets ​ 4,987 ​ ​ 5,138 Deferred tax liabilities: ​ ​ ​ ​ ​ Right-of-Use Assets ​ ( 2,867 ) ​ ​ ( 2,957 ) Depreciation ​ ( 1,752 ) ​ ​ ( 1,775 ) Amortization acquired intangibles ​ ( 2,208 ) ​ ​ ( 2,880 ) Inventory ​ — ​ ​ ( 64 ) Goodwill ​ ( 66 ) ​ ​ ( 49 ) Other deferred tax liabilities ​ ( 129 ) ​ ​ ( 61 ) Net deferred tax liabilities $ ( 2,035 ) ​ $ ( 2,648 ) ​ The Company’s change in its valuation allowance account with respect to the deferred tax asset is as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ 2021 2020 Balance, beginning of year $ 63,609 ​ $ 54,137 Change in valuation allowance ​ 19,512 ​ ​ 9,472 Balance, end of year $ 83,121 ​ $ 63,609 ​ The valuation allowance increased during the year ended December 31, 2021 as compared to the year ended December 31, 2020, primarily as a result of the U.S. operating losses incurred, stock-based compensation windfall benefits and research and development tax credit carryforwards generated during the year. In determining the need for a valuation allowance, the Company has given consideration to the cumulative book income and loss positions of each of its entities as well as its worldwide cumulative book loss position. The Company has assessed, on a jurisdictional basis, the available means of recovering deferred tax assets, including the ability to carryback net operating losses (NOLs), the existence of reversing taxable temporary differences, the availability of tax planning strategies, and forecasted future taxable income. At December 31, 2021, the Company maintains a full valuation allowance against its worldwide net deferred tax assets. As of December 31, 2021, the Company had U.S. federal NOLs of approximately $ 267.2 million. U.S. federal NOLs generated through December 31, 2017, of approximately $ 108.5 million expire at various dates through 2037, and U.S. federal NOLs generated in the tax years beginning after December 31, 2017 of approximately $ 158.7 million do not expire. As of December 31, 2021, the Company had $ 17 8.8 million of state NOLs, approximately $168.8 million expire at various dates through 2041, and certain state NOLs of approximately $10.0 million do not expire. As of December 31, 2021, the Company had U.S. federal tax credit carryforwards of approximately $ 5.1 million that expire at various dates F-25 Table of Contents through 2041. As of December 31, 2021, the Company had U.S. state tax credit carryforwards of approximately $ 1.3 million that expire at various dates through 2036. Under Sections 382 and 383 of the U.S. Internal Revenue Code, if a corporation undergoes an ownership change, the corporation’s ability to use its pre-change NOLs and other pre-change tax attributes, such as research tax credits, to offset its post-change income and taxes may be limited. In general, an ownership change generally occurs if there is a cumulative change in its ownership by 5 % stockholders that exceeds 50 percentage points over a rolling three-year period. Similar rules may apply under U.S. state tax laws. Under the Tax Cuts and Jobs Act of 2017 (TCJA), the use of federal NOLs arising in taxable years beginning after December 31, 2017 is limited to 80% of current year taxable income and NOLs arising in taxable years ending after December 31, 2017 may not be carried back (though any such NOLs may be carried forward indefinitely). The Company may have experienced an ownership change in the past and may experience ownership changes in the future as a result of future transactions in its share capital, some of which may be outside of the control of the Company. As a result, if the Company earns net taxable income, its ability to use its pre-change NOLs, or other pre-change tax attributes, to offset U.S. federal and state taxable income and taxes may be subject to significant limitations. The Coronavirus Aid, Relief and Economic Security Act (the CARES Act) was enacted in the United States on March 27, 2020. The CARES Act is an emergency economic stimulus package that includes spending and tax breaks to strengthen the United States economy and fund a nationwide effort to curtail the effect of COVID-19. While the CARES Act provides extensive tax changes in response to the COVID-19 pandemic, the provisions do not have a significant impact on the Company’s financial results. In July 2021, the Company filed for a $ 2.1 million refund under the CARES Act relating to an employee retention credit (ERC). The ERC is a refundable payroll tax credit. The Company expects receipt of the ERC refund during the first half of 2022, and this amount is included in prepaid expenses and other current assets on the consolidated balance sheet as of December 31, 2021. The Company accounts for uncertain tax positions using a more likely than not threshold for recognizing uncertain tax positions. The evaluation of uncertain tax positions is based on factors that include, but are not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The Company evaluates uncertain tax positions on an ongoing basis and adjusts the level of the liability to reflect any subsequent changes in the relevant facts surrounding the uncertain positions. The Company accounts for interest and penalties related to uncertain tax positions as a component of its benefit (provision) for income taxes. For the years ended December 31, 2021, 2020, and 2019, the Company had no tax reserves accrued for uncertain tax positions and there were no accrued interest or penalties in the consolidated statements of operations. The Company is subject to taxation in the United States as well as the Netherlands, Sweden, and China. At December 31, 2021, the Company is generally no longer subject to examination by taxing authorities in the United States for years prior to 2018. However, NOLs and credits in the United States may be subject to adjustments by taxing authorities in future years in which they are utilized. The Company’s foreign subsidiaries remain open to examination by taxing authorities from 2016 onward. As of December 31, 2021, the Company’s foreign subsidiaries had immaterial undistributed earnings and the tax payable on the earnings that are indefinitely reinvested would be immaterial. F-26 Table of Contents 7. Stockholders’ equity Stock-based compensation Stock-based compensation expense for all stock awards consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 2019 Cost of product revenue $ 471 ​ $ 189 ​ $ 86 Cost of service and other revenue 403 ​ 311 ​ 238 Research and development 1,807 ​ 1,129 ​ 718 Selling, general, and administrative 13,294 ​ 8,470 ​ 5,346 Total stock-based compensation $ 15,975 ​ $ 10,099 ​ $ 6,388 ​ At December 31, 2021, there was $ 35.8 million of total unrecognized compensation cost related to unvested stock options and restricted stock units which is expected to be recognized over the remaining weighted-average vesting period of 2.9 years. Stock-based compensation plans 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 December 31, 2021, 709,772 shares were outstanding. 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, expired, 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 December 31, 2021, 2,026,021 shares were outstanding and there were 1,434,072 shares available for grant under the 2017 Plan. 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 3, 2022, the number of shares of common stock available for issuance under the 2017 plan was automatically increased by 1,469,428 shares. In December 2017, the Company adopted the 2017 Employee Stock Purchase Plan (the 2017 ESPP). As December 31, 2019, the 2017 ESPP allowed for the issuance of up to 612,572 shares of common stock. As of December 31, 2021, 1,137,595 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 367,357 shares on January 3, 2022 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. F-27 Table of Contents Warrants The following table summarizes the Company’s outstanding warrants: ​ ​ ​ ​ ​ ​ ​ Weighted ​ Issued and ​ Average ​ exercisable Exercise Price As of December 31, 2020 10,000 ​ $ 21.00 Issued — ​ — Exercised ( 10,000 ) ​ 21.00 Cancelled — ​ ​ — As of December 31, 2021 — ​ $ — ​ Stock options Under the 2007 and 2017 Plans, 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. Option activity is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ Remaining contractual ​ 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 439,209 ​ $ 62.06 ​ ​ ​ ​ ​ Exercised ( 516,804 ) ​ $ 15.24 ​ ​ ​ ​ ​ Cancelled ( 211,637 ) ​ $ 36.32 ​ ​ ​ ​ ​ Outstanding at December 31, 2021 2,204,813 ​ $ 25.36 ​ 6.76 ​ $ 44,813 Exercisable at December 31, 2021 1,493,289 ​ $ 16.34 ​ 5.90 ​ $ 39,191 Vested and expected to vest at December 31, 2021 2,204,813 ​ $ 25.36 ​ 6.76 ​ $ 44,813 ​ Restricted stock awards 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 stock awards were granted during the years ended December 31, 2021, 2020, or 2019. As of December 31, 2021, the Company had 39,803 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. A summary of RSU activity is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ Weighted-average ​ ​ Aggregate ​ ​ ​ grant date fair ​ remaining contractual ​ ​ intrinsic value ​ Shares value per share ​ life (in years) ​ ​ (in thousands) Unvested RSUs as of December 31, 2020 478,581 $ 28.08 ​ 8.83 ​ $ 22,254 Granted 428,235 ​ $ 58.20 ​ ​ ​ ​ ​ Vested ( 267,189 ) ​ $ 27.31 ​ ​ ​ ​ ​ Cancelled ( 109,756 ) ​ $ 44.64 ​ ​ ​ ​ ​ Unvested RSUs as of December 31, 2021 529,871 ​ ​ 49.32 ​ 9.68 ​ $ 22,467 Expected to convert at December 31, 2021 529,871 ​ $ 49.32 ​ ​ ​ $ 22,467 ​ F-28 Table of Contents ​ 8. 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. 900 Middlesex Turnpike Lease The Company’s primary lease is the 900 Middlesex Turnpike Lease. On October 2, 2018, the Company entered into a 137 -month operating lease for the Company’s new headquarters in Billerica, Massachusetts. The lease is for approximately 92,000 square feet of office and laboratory space and commenced on April 1, 2019. The lease contains a period of free rent and escalating monthly rent payments. As part of the lease, the Company was required to enter into a $ 1.0 million Letter of Credit drawable by the lessor under specifically outlined conditions, which will be subsequently reduced throughout the lease term. Pursuant to a work letter entered into in connection with the 900 Middlesex Turnpike Lease, the landlord contributed an aggregate of $ 8.2 million toward the cost of construction and tenant improvements for the building. Under the lease, the Company has the option to extend the lease for two successive five-year terms, and the renewal options are not reasonably certain to be exercised. In applying the ASC 842 transition guidance, the 900 Middlesex Turnpike Lease remained classified as an operating lease and the Company recorded ROU assets of $ 12.2 million and lease liability of $ 22.7 million on the effective date. The difference between the ROU and the lease liability was driven by the Company derecognizing deferred rent of $ 3.0 million and the lease obligation incentive of $ 7.6 million. The Company is recognizing rent expense on a straight-line basis throughout the remaining term of the leases. 48 Tvistevägen The Company has multiple leases at 48 Tvistevägen Umeå, Sweden for laboratory spaces, manufacturing spaces, and office space (the Uman leases). All of these Uman leases have been assessed as operating leases. In applying the ASC 842 transition guidance, the Uman leases remained classified as operating leases and the Company recorded ROU assets of less than $ 0.1 million and lease liability of less than $ 0.1 million on the effective date. The Company is recognizing rent expense on a straight-line basis throughout the remaining term of the leases. 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, Operating leases (in thousands) ​ 2021 ​ 2020 Lease costs (1) ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 2,660 ​ $ 2,663 Total lease cost ​ $ 2,660 ​ $ 2,663 ​ ​ ​ ​ ​ ​ ​ Other information ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 3,388 ​ $ 2,108 Weighted average remaining lease term (years) ​ ​ 8.6 ​ ​ 9.8 Weighted average discount rate ​ ​ 9.73 % ​ ​ 9.73 % (1) Short-term lease costs and variable lease costs incurred by the Company for the year ended December 31, 2021 were considered immaterial. F-29 Table of Contents Rent expense is calculated on a straight-line basis over the term of the lease. Rent expense recognized under all leases was $ 5.4 million, $ 4.8 million, and $ 3.3 million for the years ended December 31, 2021, 2020, and 2019, respectively. Note that the Company adopted ASC 842 effective January 1, 2020 using the required modified retrospective approach and utilizing the effective date as its date of initial application. Therefore, the amount disclosed pertaining to the year ended December 31, 2019 is presented under previous accounting guidance and is not comparable to the amounts recorded in the 2021 and 2020 periods under ASC 842. Future minimum commitments under ASC 842 under the Company’s operating leases in effect at December 31, 2021 were as follows: ​ ​ ​ ​ Maturity of lease liabilities (in thousands) ​ As of December 31, 2021 2022 ​ $ 3,466 2023 ​ ​ 3,515 2024 ​ ​ 3,557 2025 ​ ​ 3,655 2026 ​ ​ 3,765 thereafter ​ ​ 14,782 Total lease payments ​ $ 32,740 Less: imputed interest ​ ​ 10,850 Total operating lease liabilities ​ $ 21,890 ​ ​ 9. Commitments and contingencies License agreements 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 board member of the Company’s Board of Directors was affiliated with Tufts. The License Agreement, which was subsequently amended, is exclusive and sub licensable, 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 years ended December 31, 2021, 2020, and 2019, the Company recorded royalty expense of $ 1.6 million, $ 1.1 million and $ 1.0 million, respectively, in cost of product revenue on the consolidated statements of operations. During the year ended December 31, 2020, the Company incurred $ 1.0 million in cost of collaboration and license revenue owed to Tufts related to sublicensing certain technology and intellectual property to Abbott Laboratories (Abbott) (see Note 13). Other licenses During the year ended December 31, 2012, the Company entered into a license agreement for certain intellectual property with a third party. The non-exclusive, non-sublicensable third party’s license provides the Company access to certain patents specifically for protein detection and shall be in effect until the expiration of the last licensed patent. In consideration for these rights, the Company committed to certain license fees, milestone payments, minimum annual royalties and a mid-single digit royalty. The Company is required to make mid-single digit royalty payments on net sales of products and services which utilize the licensed technology. The Company must pay the greater of calculated royalties on net sales or an annual minimum royalty of $ 50 thousand. In September 2019, all remaining patents related to the intellectual property expired and the license agreement terminated. As this agreement was terminated in 2019, the Company recorded no royalty expense during the years ended December 31, 2021 and 2020. During the year ended December 31, 2019, the Company recorded royalty expense of $ 0.8 million in cost of product revenue on the consolidated statements of operations. F-30 Table of Contents 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. ​ 10. Notes payable Loan agreement On April 14, 2014, the Company executed a loan agreement with a lender, as subsequently amended. As of December 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 was 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. On October 1, 2021, the Company made the final principal payment, including end of term fees, of $ 2.0 million related to the loan agreement. 11. “At-the-market offering” On March 19, 2019, the Company entered into the Sales Agreement with Cowen with respect to an “at-the-market” offering program under which the Company could offer and sell, from time to time at its sole discretion, shares of its common stock, having an aggregate offering price of up to $ 50.0 million through Cowen as its sales agent. On June 5, 2019, the Company issued approximately 2.2 million shares of common stock at an average stock price of $ 22.73 per share pursuant to the terms of the Sales Agreement. The “at-the-market” offering resulted in gross proceeds of $ 49.7 million. The Company incurred $ 1.7 million in issuance costs associated with the “at-the-market” offering, resulting in net proceeds to the Company of $ 48.0 million. On August 6, 2020, the Company delivered written notice to Cowen to terminate the Sales Agreement, which termination the parties agreed to make immediately effective. 12. Underwritten public offerings On August 8, 2019, the Company entered into an underwriting agreement with J.P. Morgan and Leerink, as representatives of the several underwriters, relating to an underwritten public offering of approximately 2.7 million shares of the Company’s common stock, par value $ 0.001 per share. The underwritten public offering resulted in gross proceeds of $ 69.0 million. The Company incurred $ 4.5 million in issuance costs associated with the underwritten public offering, resulting in net proceeds to the Company of $ 64.5 million. 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, Leerink, 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 F-31 Table of Contents 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. 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 less than $ 0.1 million for the years ended December 31, 2021, 2020, and 2019 associated with these licenses. During the year ended December 31, 2020, the Company recognized $ 1.2 million of previously deferred revenue as a result of entering into a license agreement with a diagnostics company. As of December 31, 2021 and 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. 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 diagnostics. Abbott has paid the Company an initial license fee of $ 10.0 million in connection with the execution of the Abbott License Agreement, which was recognized as license revenue for the year ended December 31, 2020. Abbott has also agreed to pay the Company milestone fees subject to the achievement by Abbott of certain development, regulatory and commercialization milestones and low single-digit royalties on net sales of licensed products. 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 year ended December 31, 2021 and 2020, the Company recognized no revenue and $ 10.0 million, respectively, within collaboration and license revenue related to the initial license fee under the Abbott License Agreement. ​ 14. Employee benefit plans The Company sponsors a 401(k) savings plan for employees. The Company may make discretionary contributions for each 401(k) plan year. During the years ended December 31, 2021, 2020, and 2019, the Company made contributions of $ 1.1 million, $ 0.7 million, and $ 0.5 million, respectively. 15. Business combinations UmanDiagnostics AB On August 1, 2019, the Company completed its acquisition of Uman for an aggregate purchase price of $ 21.2 million, comprised of (i) $ 15.7 million in cash plus (ii) 191,152 shares of common stock (representing $ 5.5 million based on the closing prices of the Company’s common stock on the Nasdaq Global Market on July 1, 2019 and August 1, 2019, the dates of issuance). The acquisition of Uman closed with respect to 95 % of the outstanding shares of capital stock of Uman on July 1, 2019 and with respect to the remaining 5 % of the outstanding shares of capital stock of Uman on August 1, 2019. F-32 Table of Contents Uman supplies 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. This acquisition was considered a business acquisition for accounting purposes. The Company has accounted for the acquisition of Uman as a purchase of a business under U.S. GAAP. Under the acquisition method of accounting, the assets and liabilities of Uman are recorded as of the acquisition date of July 1, 2019, at their respective fair values, and consolidated with those of the Company. Purchase consideration in excess of the amounts recognized for the net assets acquired was recognized as goodwill and is not expected to be tax deductible in any taxing jurisdiction. The following table summarizes the acquisition accounting, net of $ 1.2 million in cash and cash equivalents acquired (in thousands): ​ ​ ​ ​ Purchase price: ​ ​ ​ Cash and stock paid ​ $ 21,217 Cash and cash equivalents acquired ​ ​ 1,221 Purchase price, net ​ ​ 19,996 ​ ​ ​ ​ Assets (liabilities) acquired: ​ ​ ​ Accounts receivable ​ $ 638 Inventory ​ ​ 1,680 Prepaids and other current assets ​ ​ 114 Property and equipment ​ ​ 33 Intangibles ​ ​ 13,450 Goodwill ​ ​ 8,111 Accounts payable ​ ​ ( 20 ) Accrued expense and other current liabilities ​ ​ ( 871 ) Deferred tax liabilities ​ ​ ( 3,139 ) Total ​ $ 19,996 ​ Revenue and net income related to Uman’s operations were $ 1.8 million and $ 0.1 million, respectively for the year ended December 31, 2021, and is included in the Company’s consolidated statement of operations. Revenue and net loss related to Uman’s operations were $ 1.5 million and $ 0.1 million, respectively, for the year ended December 31, 2020, and is included in the Company’s consolidated statement of operations. Revenue and net income related to Uman’s operations were $ 1.1 million and less than $ 0.1 million, respectively, for the six months following the July 1, 2019 acquisition date, and is included in the Company’s consolidated statements of operations for the year ended December 31, 2019. The following unaudited pro forma information presents the condensed consolidated results of operations of the Company and Uman for the year ended December 31, 2019, as if the acquisition of Uman had been completed on January 1, 2018. These pro forma condensed consolidated financial results have been prepared for comparative purposes only and include certain adjustments that reflect pro forma results of operations, such as increased amortization for the fair value of acquired intangible assets, increased cost of sales related to the inventory valuation adjustment, and adjustments relating to the tax effect of combining the Company and Uman businesses. F-33 Table of Contents The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and Uman. Accordingly, these unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of the results of operations that actually would have been achieved had the acquisition occurred as of January 1, 2018, nor are they intended to represent or be indicative of future results of operations (in thousands): ​ ​ ​ ​ ​ Year Ended ​ December 31, 2019 Revenue (unaudited) $ 57,597 Pre-tax loss (unaudited) $ ( 38,636 ) ​ During the year ended December 31, 2021 and 2020, the Company incurred no costs associated with the acquisition of Uman. During the year ended December 31, 2019, the Company incurred $ 1.9 million in costs associated with the acquisition of Uman. Costs associated with the acquisition of Uman are recorded as selling, general, and administrative expenses within the consolidated statements of operations. 16. Goodwill and intangible assets The changes in the carrying amount of goodwill are as follows (in thousands): ​ ​ ​ ​ ​ Goodwill Balance as of December 31, 2020 $ 10,460 Cumulative translation adjustment ​ ( 828 ) Balance as of December 31, 2021 $ 9,632 ​ Acquired intangible assets consist of the following (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ ​ ​ Estimated ​ ​ ​ ​ ​ ​ Cumulative ​ ​ ​ ​ ​ Useful ​ Gross Carrying ​ Accumulated ​ Translation ​ Net Carrying ​ Weighted Average ​ Life (in years) Value Amortization Adjustment Value Life R emaining (in years) Know-how 8.5 ​ $ 13,000 ​ $ ( 3,825 ) ​ $ 241 ​ $ 9,416 ​ 6.0 Developed technology 7 ​ ​ 1,650 ​ ​ ( 1,277 ) ​ ​ — ​ ​ 373 ​ 3.1 Customer relationships 8.5 - 10 ​ 1,360 ​ ( 792 ) ​ ​ 2 ​ 570 ​ 6.1 Non-compete agreements 5.5 ​ ​ 340 ​ ​ ( 170 ) ​ ​ 5 ​ ​ 175 ​ 3.0 Trade names 3 ​ 50 ​ ( 50 ) ​ ​ — ​ — ​ — Total ​ ​ $ 16,400 ​ $ ( 6,114 ) ​ $ 248 ​ $ 10,534 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ Estimated ​ ​ ​ ​ ​ ​ Cumulative ​ ​ ​ ​ ​ Useful ​ Gross Carrying ​ Accumulated ​ Translation ​ Net Carrying ​ Weighted 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 ​ 7.0 Developed technology 7 ​ ​ 1,650 ​ ​ ( 1,036 ) ​ ​ — ​ ​ 614 ​ 4.1 Customer relationships 8.5 - 10 ​ 1,360 ​ ( 618 ) ​ ​ 12 ​ 754 ​ 7.1 Non-compete agreements 5.5 ​ ​ 340 ​ ​ ( 102 ) ​ ​ 31 ​ ​ 269 ​ 4.0 Trade names 3 ​ 50 ​ ( 49 ) ​ ​ — ​ 1 ​ 0.1 Total ​ ​ $ 16,400 ​ $ ( 4,101 ) ​ $ 1,417 ​ $ 13,716 ​ ​ ​ The Company recorded amortization expense of $ 2.0 million, $ 2.1 million, and $ 1.4 million for the years ended December 31, 2021, 2020, and 2019, respectively. Amortization of 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 goods sold. F-34 Table of Contents Future estimated amortization expense of acquired intangible assets as of December 31, 2021 is as follows (amounts in thousands): ​ ​ ​ ​ ​ As of December 31, 2021 2022 $ 1,930 2023 ​ 1,848 2024 ​ 1,733 2025 ​ 1,618 2026 ​ 1,589 Thereafter ​ 1,816 Total amortization expense $ 10,534 ​ ​ 17. Related party transactions As described in Note 9, in June 2007, the Company entered into a license agreement for certain intellectual property with Tufts. Tufts is a related party to the Company due to Tufts’ equity ownership in the Company and because a board member of the Company’s Board of Directors was affiliated with Tufts. During the years ended December 31, 2021, 2020, and 2019, the Company recorded royalty expense of $ 1.6 million, $ 1.1 million, and $ 1.0 million, respectively, in cost of product revenue on the consolidated statements of operations. During the year ended December 31, 2020, the Company also incurred $ 1.0 million in cost of collaboration and license revenue owed to Tufts related to sublicensing certain technology and intellectual property to Abbott. 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 $ 0.2 million, $ 0.1 million, and $ 0.1 million for the years ended December 31, 2021, 2020, and 2019, respectively. On November 28, 2018, the Company entered into a sponsor agreement with Powering Precision Health (PPH), a 501(c)(6) not-for-profit entity of which an executive of the Company is a board member, through December 31, 2018. The agreement committed a maximum of $ 120,000 in funds and services to be provided to PPH for the term of the agreement. On November 14, 2019, the Company entered into the first amendment to the PPH sponsorship agreement. The agreement amended the $ 120,000 annual committed maximum amount to $ 200,000 for the annual committed amount. The agreement is terminable by either party and does not bind the Company to beyond the term of the agreement. For the years ended December 31, 2021 and 2020, the Company did not make any contributions. For the year ended December 31, 2019, the Company had total contributions of $ 0.1 million. ​ ​ 18. Subsequent events On January 28, 2022, the Company entered into a multi-year lease agreement for approximately 53,000 square feet of new principal office space and approximately 32,770 square feet of new laboratory space in Bedford, Massachusetts. The initial lease term is eight years and nine months beginning on the earlier of the Company occupancy, or May 1, 2022. The Company was required to provide an initial security deposit of $ 0.9 million, which was provided in a form of a letter of credit to the landlord during 2021, and is included in the Company’s restricted cash balance as of December 31, 2021. The security deposit is scheduled to be reduced to $ 0.5 million after 60 months . ​ F-35