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 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, 2022. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were not effective at a reasonable assurance level as of December 31, 2022, due to the material weaknesses described below in Management’s Report on Internal Control over Financial Reporting. 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 Rules 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, 2022, 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 not effective at the reasonable assurance level as of December 31, 2022, due to the material weaknesses described below. ​ A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of the Company's annual or interim financial statements will not be prevented or detected on a timely basis. ​ Based on the evaluation described above, our management concluded that control deficiencies existed as of December 31, 2022, and that these control deficiencies constituted material weaknesses in our internal control over financial reporting. The material weaknesses related to the operating effectiveness of our internal control associated with (i) the accounting for inventory, including excess and obsolescence reserves, (ii) the accounting for salary and commissions expense, (iii) the financial statement close process, including financial reporting, share-based compensation and non-recurring transactions such as impairment of assets and accounting for leases, and (iv) the accounting for property and equipment, net. The primary cause of these control deficiencies is that we did not maintain a sufficient number of qualified personnel with requisite expertise in key accounting and finance functions, including following the implementation of the Restructuring Plan in the second half of 2022. In addition, our reliance on a significant number of end user computing tools requires additional procedures to verify the completeness and accuracy of information used within our analyses. ​ There were no material misstatements as a result of the material weaknesses discussed above. If not remediated, or if we identify further material weaknesses in our internal control, our failure to establish and maintain effective 84 Table of Contents disclosure controls and procedures and internal control over financial reporting could result in material misstatements in our consolidated financial statements or a failure to meet our reporting and financial obligations. ​ The Company’s independent registered public accounting firm, Ernst & Young LLP, has also issued an audit report on the Company’s internal control over financial reporting, which is included elsewhere in this Annual Report on Form 10-K. ​ Management’s Plan to Remediate the Material Weaknesses Management, with oversight from the Audit Committee of our Board of Directors, is taking steps to remediate the control deficiencies which resulted in the material weaknesses described above by implementing changes to our internal control over financial reporting. Our plans for remediation include, but are not limited to, the efforts summarized below, which have been or are in the process of being implemented: ​ ● we have hired, and will continue to hire, additional personnel (including those with public company experience) who have the appropriate level of expertise in the areas of accounting, financial reporting, and internal controls commensurate with the volume and complexity of our reporting requirements; ● we have engaged accounting advisory consultants to provide additional depth and breadth in our period end close, technical accounting, and financial reporting capabilities until we have filled vacancies with qualified personnel; ● we will engage a third-party service provider to perform an assessment of our internal control design and related documentation; ● we have engaged a third-party consultant to assess our current enterprise resource planning system and identify opportunities to enhance our use of the system through automating certain controls and processes; and ● we have engaged an accounting advisory consultant to conduct additional trainings on a regular basis related to internal control over financial reporting to our team members including, but not limited to, finance and accounting personnel. ​ We are also developing a plan to manage, on an ongoing basis, the impact of personnel turnover in the areas of accounting and financial reporting by broadening the understanding and knowledge of a larger group of personnel who can thereby work to support our operations during periods of reduced staffing. ​ We expect to continue our efforts to remediate the material weaknesses as described above through fiscal year 2023. We believe that the implementation of the above steps will allow us to address the deficient controls within our internal control environment, which will facilitate the remediation of the material weaknesses. As we continue to evaluate and work to improve our internal control over financial reporting, we will take additional measures to address control deficiencies and we may modify certain of the remediation measures described above. Following our design and implementation of our remediation efforts, we will need to demonstrate their operating effectiveness. We will not be able to consider the material weaknesses remediated until the applicable remedial controls operate for a sufficient period of time and our management has concluded, through testing, that our controls are operating effectively. ​ Changes in Internal Control over Financial Reporting ​ Other than related to the changes outlined above to remediate the material weaknesses described above, there have been no changes in our internal control over financial reporting during the fiscal quarter ended December 31, 2022 that have materially affected, or are reasonably likely to materially affect, our internal control 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, 2022, 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, because of the effect of the material weaknesses described below on the achievement of the objectives of the control criteria, Quanterix Corporation (the Company) has not maintained effective internal control over financial reporting as of December 31, 2022, based on the COSO criteria. A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of the company’s annual or interim financial statements will not be prevented or detected on a timely basis. The following material weaknesses have been identified and included in management’s assessment. Management has identified material weaknesses in internal controls related to (i) the accounting for inventory, including excess and obsolescence reserves, (ii) the accounting for salary and commissions expense, (iii) the financial statement close process, including financial reporting, share-based compensation and non-recurring transactions such as impairment of assets and accounting for leases, and (iv) the accounting for property and equipment, net. We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2022, and December 31, 2021, the related consolidated statements of operations, comprehensive loss, stockholders' equity and cash flows for each of the three years in the period ended December 31, 2022, and the related notes. These material weaknesses were considered in determining the nature, timing and extent of audit tests applied in our audit of the 2022 consolidated financial statements, and this report does not affect our report dated March 6, 2023, which 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 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 86 Table of Contents 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 6, 2023 ​ Item 9B. OTHER INFORMATION Not applicable. 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 2023 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 2023 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 2023 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 2023 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 2023 Annual Meeting of Stockholders and is incorporated herein by reference. 87 Table of Contents 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. (2) Financial Statement Schedules Financial statement schedules have been omitted since they either are not required, not applicable, or the information is otherwise included. ​ (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 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 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 88 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.2.3+ ​ 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 10.3.1 + Amended and Restated Employment Agreement, dated April 25, 2022, between the Registrant and E. Kevin Hrusovsky ​ ​ ​ 8-K ​ 4/29/2022 ​ 001-38319 10.3.2 + Separation Agreement, effective as of August 8, 2022, between the Registrant and E. Kevin Hrusovsky ​ ​ ​ 8-K ​ 8/8/2022 ​ 001-38319 10.4+ ​ Employment Agreement, dated June 22, 2021, between the Registrant and Michael Doyle ​ ​ ​ 8-K ​ 6/28/2021 ​ 001-38319 10.5+ ​ Amended and Restated Employment Agreement, dated April 25, 2022, between the Registrant and Dr. Masoud Toloue ​ ​ ​ 8-K ​ 4/29/2022 ​ 001-38319 10.6+ ​ Employment Agreement, dated March 28, 2022, between the Registrant and Dan Pikora ​ ​ ​ 8-K ​ 9/8/2022 ​ 001-38319 10.7.1* ​ 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 10.7.2* ​ Second Amendment, dated August 22, 2017, to the Exclusive License Agreement between the Registrant and Tufts University ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.7.3 @ Third Amendment, dated September 25, 2020, to the Exclusive License Agreement between the Registrant and Tufts University ​ ​ ​ 10-Q ​ 11/6/2020 ​ 001-38319 89 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.8.1* ​ Supply and Manufacturing Agreement, dated September 14, 2011, between the Registrant and STRATEC Biomedical AG ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.8.2 ​ 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 10.9.1* ​ 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 10.9.2* ​ 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 10.10* ​ Manufacturing Services Agreement, dated November 23, 2016, between the Registrant and Paramit Corporation ​ ​ ​ S-1 ​ 11/9/2017 ​ 333-221475 10.11+ ​ Form of Indemnification Agreement ​ ​ ​ S-1/A ​ 11/27/2017 ​ 333-221475 10.12 ​ Lease Agreement by and between SSI 900 Middlesex MA LP and the Registrant, dated October 2, 2018. ​ ​ ​ 8-K ​ 10/5/2018 ​ 001-38319 10.13 ​ Lease Agreement by and between the Registrant and XChange Owner LLC, dated January 28, 2022 . ​ ​ ​ 8-K ​ 1/31/2022 ​ 001-38319 10.14+ ​ Amended and Restated 2018 Non-Employee Director Compensation Policy ​ ​ 10-K ​ 3/1/2022 ​ 001-38319 21.1 ​ Subsidiaries of Registrant ​ ​ 10-K ​ 3/5/2021 ​ 001-38319 23.1 ​ Consent of Ernst & Young LLP ​ X ​ ​ ​ ​ ​ ​ 90 Table of Contents Exhibit Number Exhibit Description Filed Herewith Incorporated by Reference herein from Form or Schedule Filing Date SEC File/ Reg. Number ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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) ​ ​ ​ ​ ​ ​ ​ ​ + 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. @ Portions of this document (indicated by “[***]”) have been omitted because such information is not material and is the type of information that the Registrant treats as private or confidential. Item 16. FORM 10-K SUMMARY Not applicable. ​ 91 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 6, 2023 By: /s/ MASOUD TOLOUE, PH.D. ​ ​ Masoud Toloue, Ph. D. ​ ​ President 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/ MASOUD TOLOUE, PH.D. ​ President and Chief Executive Officer and Director (Principal Executive Officer) ​ March 6, 2023 Masoud Toloue, Ph. D. ​ ​ ​ ​ ​ /s/ MICHAEL A. DOYLE ​ Chief Financial Officer ​ March 6, 2023 Michael A. Doyle (Principal Financial Officer and Principal Accounting Officer) ​ ​ ​ ​ ​ /s/ Martin D. Madaus, Ph.D. ​ Chairman ​ March 6, 2023 Martin D. Madaus, Ph.D. ​ ​ ​ ​ ​ /s/ BRIAN J. BLASER ​ Director ​ March 6, 2023 Brian J. Blaser ​ ​ ​ ​ ​ /s/ KEITH L. CRANDELL ​ Director ​ March 6, 2023 Keith L. Crandell ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ KAREN A. FLYNN ​ Director ​ March 6, 2023 Karen A. Flynn ​ ​ ​ ​ ​ /s/ SARAH E. HLAVINKA ​ Director ​ March 6, 2023 Sarah E. Hlavinka ​ ​ ​ ​ ​ /s/ PAUL M. MEISTER ​ Director ​ March 6, 2023 Paul M. Meister ​ ​ ​ ​ ​ ​ ​ ​ ​ /s/ LAURIE J. OLSON ​ Director ​ March 6, 2023 Laurie J. Olson ​ ​ ​ ​ ​ /s/ DAVID R. WALT, PH.D. ​ Director ​ March 6, 2023 David R. Walt, Ph.D. ​ ​ ​ ​ ​ ​ ​ 92 Table of Contents INDEX TO CONSOLIDATED FINANCIAL STATEMENTS QUANTERIX CORPORATION Years ended December 31, 2022, 2021, and 2020 ​ ​ ​ 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, 2022 and 2021, 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, 2022, and the related notes (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, 2022 and 2021, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2022, 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, 2022, 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 6, 2023 expressed an adverse 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 of December 31, 2022, the Company had recognized inventory of $16.8 million. 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 sales requirements. 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 supporting the Company’s estimate. 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 evaluated inventory levels compared to forecasted demand, historical sales and specific product considerations. We performed inquiries with appropriate non-financial personnel, including supply chain employees, regarding obsolete or discontinued inventory items and other factors to corroborate management's assertions regarding qualitative judgments about discontinued, slow moving and obsolete inventories. 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 6, 2023 ​ ​ F-3 ​ Table of Contents Quanterix Corporation Consolidated Balance Sheets (amounts in thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 December 31, 2021 Assets ​ ​ ​ ​ ​ Current assets: ​ ​ ​ Cash and cash equivalents $ 338,740 ​ $ 396,465 Accounts receivable (less allowance for credit losses of $ 118 and $ 419 as of December 31, 2022 and December 31, 2021, respectively; including $ 89 and $ 200 due from related parties as of December 31, 2022 and December 31, 2021, respectively) 19,017 ​ 23,786 Inventory 16,786 ​ 22,190 Prepaid expenses and other current assets 6,860 ​ 6,514 Total current assets ​ 381,403 ​ 448,955 Restricted cash 2,597 ​ 2,577 Property and equipment, net 20,162 ​ 17,960 Intangible assets, net 7,516 ​ 10,534 Goodwill — ​ 9,632 Right-of-use assets ​ 21,223 ​ ​ 11,491 Other non-current assets 1,298 ​ 378 Total assets $ 434,199 ​ $ 501,527 Liabilities and stockholders’ equity ​ Current liabilities: ​ Accounts payable (including $ 0 and $ 42 to related parties as of December 31, 2022 and December 31, 2021, respectively) $ 3,836 ​ $ 9,209 Accrued compensation and benefits 10,658 ​ 13,252 Other accrued expenses 4,747 ​ 6,486 Deferred revenue (including $ 69 and $ 54 with related parties as of December 31, 2022 and December 31, 2021, respectively) 8,644 ​ 6,361 Short term lease liabilities ​ 2,687 ​ ​ 1,428 Other current liabilities ​ 386 ​ ​ 241 Total current liabilities 30,958 ​ 36,977 Deferred revenue, net of current portion 1,415 ​ 1,099 Long term lease liabilities ​ 41,417 ​ ​ 20,464 Other non-current liabilities 1,469 ​ 2,035 Total liabilities 75,259 ​ 60,575 Commitments and contingencies (Note 13) ​ ​ ​ ​ ​ Stockholders’ equity: ​ Common stock, $ 0.001 par value: ​ ​ ​ Authorized shares: 120,000,000 at December 31, 2022 and December 31, 2021, respectively; Issued and outstanding : 37,279,994 shares and 36,768,035 shares at December 31, 2022 and December 31, 2021, respectively 37 ​ 37 Additional paid-in capital 763,688 ​ 745,936 Accumulated other comprehensive income ​ ( 2,623 ) ​ ​ 441 Accumulated deficit ( 402,162 ) ​ ( 305,462 ) Total stockholders’ equity 358,940 ​ 440,952 Total liabilities and stockholders’ equity $ 434,199 ​ $ 501,527 ​ ​ The accompanying notes are an integral part of these financial statements. ​ F-4 ​ Table of Contents Quanterix Corporation Consolidated Statements of Operations (amounts in thousands, except share and per share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended ​ ​ December 31, ​ 2022 2021 2020 Product revenue (including related party activity of $ 2,634 , $ 505 , and $ 580 for the years ended December 31, 2022, 2021, and 2020, respectively) $ 69,808 ​ $ 81,062 ​ $ 44,017 Service and other revenue (including related party activity of $ 11 , $ 114 , and $ 202 for the years ended December 31, 2022, 2021, and 2020, respectively) 34,495 ​ 23,629 ​ 24,129 Collaboration revenue 649 ​ 648 ​ 11,809 Grant revenue ​ 570 ​ ​ 5,217 ​ ​ 6,422 Total revenue 105,522 ​ 110,556 ​ 86,377 Costs of goods sold: ​ ​ Cost of product revenue (including related party activity of $ 154 , $ 1,936 , and $ 205 for the years ended December 31, 2022, 2021, and 2020 respectively) 40,809 ​ 34,149 ​ 25,950 Cost of service and other revenue (including related party activity of $ 87 , $ 74 , and $ 52 for the years ended December 31, 2022, 2021, and 2020 respectively) 17,907 ​ 14,679 ​ 11,245 Cost of collaboration and license revenue (including related party activity of $ 0 , $ 0 , and $ 1,000 for the years ended December 31, 2022, 2021, and 2020 respectively) ​ — ​ ​ — ​ ​ 1,000 Total costs of goods sold, services, and licenses 58,716 ​ 48,828 ​ 38,195 Gross profit ​ 46,806 ​ ​ 61,728 ​ ​ 48,182 Operating expenses: ​ ​ Research and Development Expense (including related party activity of $ 696 , $ 565 , and $ 235 for the years ended December 31, 2022, 2021, and 2020 respectively) 25,890 ​ 27,978 ​ 20,174 Selling, general and administrative (including related party activity of $ 41 , $ 89 , and $ 37 for the years ended December 31, 2022, 2021, and 2020 respectively) 91,995 ​ 92,336 ​ 59,592 Other lease costs ​ 1,278 ​ ​ — ​ ​ — Restructuring ​ 3,755 ​ ​ — ​ ​ — Goodwill impairment ​ 8,220 ​ ​ — ​ ​ — Impairment expense ​ 17,372 ​ ​ — ​ ​ — Total operating expenses 148,510 ​ 120,314 ​ 79,766 Loss from operations ( 101,704 ) ​ ( 58,586 ) ​ ( 31,584 ) Interest income (expense), net 5,131 ​ ( 403 ) ​ ( 273 ) Other (expense) income, net ( 62 ) ​ 1,265 ​ ( 49 ) Loss before income taxes ​ ( 96,635 ) ​ ​ ( 57,724 ) ​ ​ ( 31,906 ) Income tax (expense) benefit ​ ( 65 ) ​ ​ 36 ​ ​ 376 Net loss $ ( 96,700 ) ​ $ ( 57,688 ) ​ $ ( 31,530 ) Net loss per share, basic and diluted $ ( 2.61 ) ​ $ ( 1.60 ) ​ $ ( 1.07 ) Weighted-average common shares outstanding, basic and diluted 36,990,965 ​ 35,997,473 ​ 29,589,132 ​ The accompanying notes are an integral part of these financial statements. ​ F-5 ​ Table of Contents ​ ​ ​ Quanterix Corporation Consolidated Statements of Comprehensive Loss (amounts in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2022 2021 ​ 2020 Net loss $ ( 96,700 ) ​ $ ( 57,688 ) ​ $ ( 31,530 ) Other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ Foreign currency translation adjustment ​ ( 3,064 ) ​ ​ ( 1,993 ) ​ ​ 2,587 Total other comprehensive loss ​ ( 3,064 ) ​ ​ ( 1,993 ) ​ ​ 2,587 Comprehensive loss $ ( 99,764 ) ​ $ ( 59,681 ) ​ $ ( 28,943 ) ​ The accompanying notes are an integral part of these financial statements. ​ ​ ​ ​ ​ F-6 ​ Table of Contents Quanterix Corporation Consolidated Statements of C as h Flows (amounts in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 Operating activities ​ ​ Net loss $ ( 96,700 ) ​ $ ( 57,688 ) ​ $ ( 31,530 ) Adjustments to reconcile net loss to net cash used in operating activities: ​ ​ ​ Depreciation and amortization expense 5,349 ​ 4,851 ​ 4,312 Inventory step-up amortization ​ — ​ ​ 275 ​ ​ 722 Credit (income) loss expense on accounts receivable ​ ( 301 ) ​ ​ 213 ​ ​ 493 Unrealized losses (gains) on foreign currency transactions ​ ( 219 ) ​ ​ 263 ​ ​ ( 20 ) Non-cash lease expense ​ 715 ​ ​ 499 ​ ​ 245 Stock-based compensation expense 15,442 ​ 15,975 ​ 10,099 Goodwill impairment ​ 8,220 ​ ​ — ​ ​ — Impairment of long-lived assets ​ 17,372 ​ ​ — ​ ​ — Non-cash interest expense — ​ 65 ​ 86 Deferred taxes ​ ( 226 ) ​ ​ — ​ ​ — Loss on disposal of fixed assets 6 ​ 89 ​ 171 Changes in operating assets and liabilities: ​ ​ ​ ​ ​ Accounts receivable 5,156 ​ ( 6,853 ) ​ ( 6,733 ) Prepaid expenses and other assets ( 568 ) ​ ( 393 ) ​ ( 3,927 ) Inventory 5,386 ​ ( 8,090 ) ​ ( 5,119 ) Other non-current assets ( 909 ) ​ ( 2 ) ​ 198 Accounts payable ( 5,362 ) ​ 2,414 ​ 649 Accrued compensation and benefits, other accrued expenses and other current liabilities ( 3,976 ) ​ 606 ​ 6,326 Operating lease liabilities ​ ( 266 ) ​ ​ ( 1,230 ) ​ ​ 316 Other non-current liabilities ​ 10 ​ ​ ( 363 ) ​ ​ ( 488 ) Deferred revenue 2,599 ​ 1,462 ​ 835 Net cash used in operating activities ​ ( 48,272 ) ​ ​ ( 47,907 ) ​ ​ ( 23,365 ) Investing activities ​ ​ ​ ​ Purchases of property and equipment ( 11,726 ) ​ ( 13,616 ) ​ ( 3,930 ) Proceeds from RADx grant on assets purchased ​ 520 ​ ​ 7,278 ​ ​ 3,304 Net cash used in investing activities ​ ( 11,206 ) ​ ​ ( 6,338 ) ​ ​ ( 626 ) Financing activities ​ ​ ​ ​ ​ Proceeds from stock options exercised 1,430 ​ 7,750 ​ 4,019 Sale of common stock in underwritten public offering, net ​ — ​ ​ 269,718 ​ ​ 91,404 Proceeds from ESPP purchase 881 ​ 1,065 ​ 888 Payments on notes payable — ​ ( 7,738 ) ​ ( 75 ) Net cash provided by financing activities ​ 2,311 ​ ​ 270,795 ​ ​ 96,236 Net increase in cash and cash equivalents ( 57,167 ) ​ 216,550 ​ 72,245 Effect of foreign currency exchange rate on cash ​ ( 538 ) ​ ​ ( 92 ) ​ ​ 158 Cash, restricted cash, and cash equivalents at beginning of period 399,042 ​ 182,584 ​ 110,181 Cash, restricted cash, and cash equivalents at end of period $ 341,337 ​ $ 399,042 ​ $ 182,584 Supplemental cash flow information ​ ​ Cash paid for interest $ — ​ $ 389 ​ $ 625 Cash paid for taxes $ 684 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Noncash transactions: ​ ​ ​ ​ ​ ​ ​ ​ Purchases of property and equipment included in accounts payable and other accrued expenses $ 152 ​ $ 229 ​ $ 1,029 Right-of-use asset obtained in exchange for lease liabilities $ 22,494 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Reconciliation of cash, cash equivalents, and restricted cash: ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents $ 338,740 ​ $ 396,465 ​ $ 181,584 Restricted cash $ 2,597 ​ $ 2,577 ​ $ 1,000 Total cash, cash equivalents, and restricted cash $ 341,337 ​ $ 399,042 ​ $ 182,584 ​ ​ The accompanying notes are an integral part of these financial statements. ​ ​ F-7 Table of Contents Quanterix Corporation Consolidated Statements of Stockholders’ Equity (amounts in thousands, except share data) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​ ​ Common ​ Common ​ Additional ​ other ​ ​ ​ ​ ​ Total ​ stock ​ stock ​ paid-in ​ comprehensive ​ ​ Accumulated ​ ​ stockholders’ ​ shares ​ value ​ capital ​ income (loss) ​ ​ deficit ​ ​ equity Balance at December 31, 2019 28,112,201 ​ $ 28 ​ $ 345,027 ​ $ ( 153 ) ​ $ ( 216,244 ) ​ $ 128,658 Issuance of capital shares: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ −Exercised stock options 407,687 ​ ​ 1 ​ ​ 4,018 ​ ​ — ​ ​ — ​ ​ 4,019 −Restricted units converted 182,036 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — −ESPP stock purchase 45,846 ​ ​ — ​ ​ 888 ​ ​ — ​ ​ — ​ ​ 888 Sale of common stock in underwritten public offering, net 3,048,774 ​ ​ 3 ​ ​ 91,401 ​ ​ — ​ ​ — ​ ​ 91,404 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 Issuance of capital shares: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ −Exercised warrants 7,347 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — −Exercised stock options 516,792 ​ ​ 1 ​ ​ 7,749 ​ ​ — ​ ​ — ​ ​ 7,750 −Restricted units converted 307,004 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — −ESPP stock purchase 29,037 ​ ​ — ​ ​ 1,065 ​ ​ — ​ ​ — ​ ​ 1,065 −Issuance of common stock 4,169 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Sale of common stock in underwritten public offering, net 4,107,142 ​ ​ 4 ​ ​ 269,714 ​ ​ — ​ ​ — ​ ​ 269,718 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 Issuance of capital shares: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ −Exercised stock options 243,792 ​ ​ — ​ ​ 1,430 ​ ​ — ​ ​ — ​ ​ 1,430 −Restricted units converted 199,938 ​ ​ — ​ ​ ( 1 ) ​ ​ — ​ ​ — ​ ​ ( 1 ) −ESPP stock purchase 57,485 ​ ​ — ​ ​ 881 ​ ​ — ​ ​ — ​ ​ 881 −Issuance of common stock 10,744 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Stock-based compensation expense — ​ ​ — ​ ​ 15,442 ​ ​ — ​ ​ — ​ ​ 15,442 Cumulative translation adjustment — ​ ​ — ​ ​ — ​ ​ ( 3,064 ) ​ ​ — ​ ​ ( 3,064 ) Net loss — ​ ​ — ​ ​ — ​ ​ — ​ ​ ( 96,700 ) ​ ​ ( 96,700 ) Balance at December 31, 2022 37,279,994 ​ $ 37 ​ $ 763,688 ​ $ ( 2,623 ) ​ $ ( 402,162 ) ​ $ 358,940 ​ The accompanying notes are an integral part of these financial statements. ​ ​ 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’s wholly owned subsidiary UmanDiagnostics AB (Uman), a Swedish company located in Umeå, Sweden, 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. Underwritten public offerings On August 6, 2020, the Company entered into an underwriting agreement with SVB Leerink LLC 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, 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. F-9 Table of Contents Liquidity The Company has recognized annual losses from operations since inception and has an accumulated deficit of $ 402.2 million as of December 31, 2022. The Company incurred net losses of $ 96.7 million, $ 57.7 million, and $ 31.5 million for the years ended December 31, 2022, 2021, and 2020, respectively. The Company had $ 338.7 million and $ 396.5 million of unrestricted cash and cash equivalents for the years ended December 31, 2022 and 2021, respectively. The Company expects that its cash and cash equivalents, as of December 31, 2022, will be sufficient to fund its 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 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. 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. Cost of revenue Cost of goods sold for products consists of HD-X, HD-1, and SR-X instrument costs from the manufacturer and related reagents and other consumables. Cost of goods sold for SP-X consists of costs based on the internal assembly of this item. Raw material part costs; inbound freight, shipping and handling costs associated with purchased goods; contract manufacturer costs; personnel costs; royalties; overhead and other direct costs related to those sales are classified as cost of goods sold for products. Cost of service and other revenue consists of raw materials, personnel costs, royalties as well as overhead and other direct costs associated with operating the Accelerator Laboratory on behalf of customers, in addition to costs related to warranties and other costs of servicing equipment at customer sites. ​ F-10 Table of Contents 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 consist primarily of personnel costs for the Company’s sales and marketing, finance, legal, human resources and general management, costs associated with shipping and handling for product sales, other general and administrative costs, as well as professional services costs, such as marketing, advertising, legal and accounting services in addition to allocated overhead costs that include facility and other overhead costs. The classification of shipping and handling costs for product sales as selling, general, and administrative expenses varies from company to company with some companies recording these as selling, general and administrative expenses and others recording such expenses within costs of goods sold for products. To the extent the classification of these shipping and handling costs differs from the reporting approach used by other companies, the Company’s gross margins may not be comparable with those reported by such other companies. Shipping and handling costs for product sales included within selling, general and administrative expenses were $ 7.2 million, $ 6.9 million and $ 4.8 million for the years ended December 31, 2022, 2021 and 2020, respectively. 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. 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, ​ 2022 2021 Cash ​ $ 32,643 ​ $ 64,372 Money market funds invested in U.S. Treasury obligations ​ 306,097 ​ 332,093 Total cash and cash equivalents ​ $ 338,740 ​ $ 396,465 ​ 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 F-11 Table of Contents 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, 2022. 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 loss when it is probable that an asset’s realizable value is less than the carrying value. The Company recorded impairment expenses during the year-end December 31, 2022. Refer to Note 7 for additional details. 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. ASC 842 requires a lessee to recognize assets and liabilities on the balance sheet for most leases. 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 some of its instruments. Software development costs are expensed as incurred until the point the Company establishes technological feasibility. Based on F-12 Table of Contents 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 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. Fair value measurements are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ ​ ​ ​ Significant ​ ​ ​ ​ ​ in active ​ Significant other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs December 31, 2022 Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents - money market funds $ 306,097 $ 306,097 ​ $ — $ — ​ F-13 Table of Contents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Quoted prices ​ Significant ​ Significant ​ ​ ​ ​ ​ in active ​ other ​ unobservable ​ ​ ​ ​ ​ markets ​ observable ​ inputs December 31, 2021 Total (Level 1) inputs (Level 2) (Level 3) Financial assets ​ ​ ​ ​ ​ Cash equivalents - money market funds $ 332,093 $ 332,093 ​ $ — $ — ​ 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, 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, 2022 and 2021, 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 41 % and 39 % of the Company’s gross trade accounts receivable balance as of December 31, 2022, and 2021, respectively. For the year ended December 31, 2022, one customer of approximately $ 13.7 million revenue accounted for 13 % of the Company’s total revenue. For the year ended December 31, 2021, no customers individually accounted for more than 10 % 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). The Company generally recognizes stock-based payments to employees and non-employees based on their grant date fair values. Stock-based compensation awards have historically consisted of stock F-14 Table of Contents options and restricted stock units. Stock-based compensation costs for employees are recognized as expense over the requisite service period, which is generally the vesting period of the respective awards. 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, 2022, 2021, and 2020. 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 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, ​ 2022 ​ 2021 ​ 2020 Risk-free interest rate 1.4 % - 4.1 % ​ 0.4 % - 1.3 % ​ 0.4 % - 1.7 % Expected dividend yield None ​ None ​ None Expected term (in years) 5.0 - 5.8 ​ 6.0 ​ 6.0 Expected volatility 55.0 % - 70.8 % ​ 49.2 % - 55.6 % ​ 43.9 % - 49.2 % Weighted-average grant date fair value $ 9.88 ​ $ 29.96 ​ $ 12.66 ​ The Company uses its historical volatility and implied volatility as a basis to estimate expected volatility in the Company’s valuation of stock options. 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 used 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- F-15 Table of Contents 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. ​ 3. Revenue The Company recognizes revenue when a customer obtains control of a promised good or service. The amount of revenue recognized reflects consideration that the Company expects to be entitled to receive in exchange for these goods and services, incentives and taxes collected from customers that are subsequently remitted to governmental authorities. Customers The Company’s customers primarily consist of entities engaged in the life sciences research market that pursue the discovery and development of new drugs for a variety of neurologic, cardiovascular, oncologic and other protein biomarkers associated with diseases. The Company’s customer base includes several of the largest biopharmaceutical companies, academic research organizations and distributors who serve certain geographic markets. Product revenue The Company’s products are composed of analyzer instruments, assay kits and other consumables such as reagents. Products are sold directly to biopharmaceutical and academic research organizations or are sold through distributors in EMEA and Asia Pacific regions. The sales of instruments are generally accompanied by an initial year of implied service-type warranties and may be bundled with assays and other consumables and may also include other items such as training and installation of the instrument and/or an extended service warranty. Revenues from the sale of products are recognized at a point in time when the Company transfers control of the product to the customer, which is generally upon installation for instruments sold to direct customers, and based upon shipping terms for assay kits and other consumables. Revenue for instruments sold to distributors is generally recognized based upon shipping terms (either upon shipment or delivery). Service and other revenue Service revenues are composed of contract research services, initial implied one-year service-type warranties, extended services contracts and other services such as training. Contract research services are provided through the Company’s Accelerator Laboratory and generally consist of fixed fee contracts. Revenues from contract research services are recognized at a point in time when the Company completes and delivers its research report on each individually completed study, or over time if the contractual provisions allow for the collection of transaction consideration for costs incurred plus a reasonable margin through the period of performance of the services. Revenues from service-type warranties are recognized ratably over the contract service period. For contract research services recognized over time, the Company uses the output method to measure the progress toward the complete satisfaction of the performance obligations. Revenues from other services are immaterial. During the first quarter of 2022, the Company entered into a Master Collaboration Agreement with Eli Lilly and Company (Lilly) establishing a framework for future projects focused on the development of Simoa immunoassays (the Lilly Collaboration Agreement). The Company also entered into a Statement of Work under the Lilly Collaboration Agreement to perform assay research and development services within the field of Alzheimer’s disease. In connection with the Lilly Collaboration Agreement, the Company received a non-refundable up-front payment of $ 5.0 million during the first quarter of 2022, and under the Statement of Work received $ 1.5 million per calendar quarter during 2022, beginning with the first quarter of 2022. The revenue has been recognized over a one-year period. The Lilly Collaboration Agreement automatically renews on a quarterly basis unless Lilly provides 100 days ’ termination notice. F-16 Table of Contents Concurrent with the execution of the Lilly Collaboration Agreement, the Company entered into a Technology License Agreement (the Lilly License) under which Lilly granted to the Company a non-exclusive license to Lilly’s proprietary P-tau217 antibody technology for potential near-term use in research use only products and services and future in vitro diagnostics applications within the field of Alzheimer’s disease. In consideration of the license, the Company paid an upfront fee, is required to make milestone payments based on the achievement of predetermined regulatory and commercial events, and will pay a royalty on net sales of licensed products. The Company concluded that the Lilly Collaboration Agreement (including the Statement of Work) and the Lilly License represented a single contract with a customer and we are accounting for the agreements as service revenue recognized over time as the services are delivered. The transaction price for the Lilly Collaboration Agreement is $ 10.9 million. Contingent amounts due to Lilly, under the Lilly License, represent variable consideration payable to a customer and will be recognized as reductions to service revenue up to the amount of the transaction price recognized, when probable. The Company is utilizing an input method to measure the delivery of services by calculating costs incurred at each period end relative to total costs expected to be incurred. During the year ended December 31, 2022, the Company recognized approximately $ 10.9 million of revenue from the Lilly Collaboration Agreement. Collaboration and license revenue The Company may enter into agreements to license the intellectual property and know-how associated with its instruments and certain antibodies in exchange for license fees and future royalties (as described below). The license agreements provide the licensee with a right to use the intellectual property with the license fee revenues recognized at a point in time as the underlying license is considered functional intellectual property. Payment terms The Company’s payment terms vary by the type and location of the customer and the products or services offered. Payment from customers is generally required in a term ranging from 30 to 45 days from date of shipment or satisfaction of the performance obligation. The Company does not provide financing arrangements to its customers. Disaggregated revenue When disaggregating revenue, the Company considered all of the economic factors that may affect its revenues. The following tables disaggregate the Company’s revenue from contracts with customers by revenue type (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2022 (in thousands) ​ North America EMEA Asia Pacific Total Product revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Instruments ​ $ 9,254 ​ ​ 8,362 ​ ​ 7,388 ​ $ 25,004 Consumable and other products ​ ​ 25,894 ​ ​ 14,514 ​ ​ 4,396 ​ ​ 44,804 Total ​ $ 35,148 $ 22,876 $ 11,784 $ 69,808 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and other revenues: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service-type warranties ​ $ 5,581 ​ $ 2,779 ​ $ 480 ​ $ 8,840 Research services ​ ​ 22,493 ​ ​ 1,013 ​ ​ 147 ​ 23,653 Other services ​ ​ 1,144 ​ ​ 722 ​ ​ 136 ​ ​ 2,002 Total ​ $ 29,218 ​ $ 4,514 ​ $ 763 ​ $ 34,495 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collaboration and license revenue ​ $ 274 ​ $ 323 ​ $ 52 ​ $ 649 ​ F-17 Table of Contents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2021 (in thousands) ​ North America 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 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2020 (in thousands) ​ North America 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 ​ 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. Accounting Standard Codification (ASC) Topic 606, Revenue from Contracts with Customers (ASC 606) provides for an exception to estimating the variable consideration for sales- and usage-based royalties related to the license of intellectual property, such that the sales- and usage-based royalty will be recognized in the period the underlying transaction occurs. The Company recognizes revenue from sales- and usage-based royalty revenue at the later of when the sale or usage occurs and the satisfaction or partial satisfaction of the performance obligation to which the royalty has been allocated. F-18 Table of Contents Changes in deferred revenue from contracts with customers were as follows (in thousands): ​ ​ ​ ​ ​ Year Ended December 31, 2022 Balance at December 31, 2021 $ 7,460 Deferral of revenue ​ 11,444 Recognition of deferred revenue ​ ( 8,845 ) Balance at December 31, 2022 $ 10,059 ​ 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, 2022 is $ 10.1 million. Of the performance obligations not yet satisfied or that are partially satisfied, $ 8.6 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 $ 10.1 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. For further discussion, refer to Note 5. Costs to obtain a contract The Company’s sales commissions are generally based on bookings of the Company. The Company has determined that certain commissions paid under its sales incentive programs meet the requirements to be capitalized as they are incremental and would not have occurred absent a customer contract. The change in the balance of costs to obtain a contract are as follows (in thousands): ​ ​ ​ ​ ​ ​ 2022 Balance at January 1 $ 440 Deferral of costs to obtain a contract ​ 1,387 Recognition of costs to obtain a contract ​ ( 1,450 ) Balance at December 31 $ 377 ​ The Company has classified the balance of capitalized costs to obtain a contract as a component of prepaid expenses and other current assets and will subsequently amortize the expense as a component of cost of goods sold and selling, general, and administrative expense over the estimated life of the contract. The Company considers potential impairment in these amounts each period. ASC 606 provides entities with certain practical expedients and accounting policy elections to minimize the cost and burden of adoption. The Company does not disclose the value of unsatisfied performance obligations for (i) contracts with original expected length of one year or less and (ii) contracts for which revenue is recognized at the amount to which the Company has the right to invoice for services performed. The Company will exclude from its transaction price any amounts collected from customers related to sales and other similar taxes. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. The Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. None of the Company’s contracts contained a significant financing component as of December 31, 2022, and 2021, respectively. F-19 Table of Contents The Company has elected to account for the shipping and handling as an activity to fulfill the promise to transfer the product, and therefore will not evaluate whether shipping and handling activities are promised services to its customers. Grant revenue The Company recognizes grant revenue as the Company 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 grants to for profit business entities from government entities, the Company has accounted for grants obtained with the National Institute of Health (NIH) under its Rapid Acceleration of Diagnostics (RADx) program by analogy to International Accounting Standards Topic 20, Accounting for Government Grants and Disclosure of Government Assistance (IAS 20) The Company accounts for grants from the Alzheimer’s Drug Discovery Foundation (ADDF) under ASC Topic 958, Not for-Profit Entities (ASC 958). Under IAS 20, grants related to assets shall be presented in the consolidated balance sheets either by recognizing the grant as deferred income (which is recognized in the consolidated statements of operations on a systematic basis over the useful life of the asset), or by deducting the grant in calculating the carrying amount of the asset (which is recognized in the consolidated statements of operations over the life of the depreciable asset as a reduced depreciation expense). Both methods are acceptable under IAS 20. The Company has elected to record grants related to assets as a deduction in calculating the carrying value of the asset. Under IAS 20, grants related to income are presented as part of the consolidated statements of operations, either separately or under a general heading. Both methods are acceptable under IAS 20. The Company has elected to record grants related to income separately on the consolidated statements of operations as grant revenue. The related expenses are recorded within operating expenses. Under ASC 958, 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 ASC 958. The Company has elected to record grants related to income separately on the consolidated statements of operations as grant revenue. The related expenses are recorded within operating expenses. RADx grant On September 29, 2020, the Company entered into WP2 with the NIH under its RADx program. The contract, which had a total award value of $ 18.2 million, accelerated the continued development, scale-up, and deployment of the novel SARS-CoV-2 antigen detection test using the Company’s Simoa technology. The contract provided funding to expand assay kit manufacturing capacity and commercial deployment readiness. Release of the $ 18.2 million of funding under WP2 was 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. The Company has received the full $ 18.2 million under WP2. During the year ended December 31, 2022, the Company recognized no grant revenue and incurred no research and development expense related to 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 RADx Grant contains 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. F-20 Table of Contents The following table summarizes the cumulative activity under the RADx Grant (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ December 31, 2021 ​ December 31, 2020 Total grant revenue from research and development activities $ 9,576 ​ $ 9,576 ​ $ 4,362 Total proceeds used for assets ​ 8,624 ​ ​ 8,104 ​ ​ 826 Total deferred proceeds for assets ​ — ​ ​ — ​ ​ 2,478 Total deferred grant revenue ​ — ​ ​ — ​ ​ 304 Total recognized $ 18,200 ​ $ 17,680 ​ $ 7,970 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total recognized $ 18,200 ​ $ 17,680 ​ $ 7,970 Total amount accrued ​ — ​ ​ — ​ ​ ( 2,968 ) Total cash received $ 18,200 ​ $ 17,680 ​ $ 5,002 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total proceeds received $ 18,200 ​ $ 17,680 ​ $ 5,002 Total proceeds reasonably assured ​ — ​ ​ 520 ​ ​ 13,198 Total RADx Grant amount $ 18,200 ​ $ 18,200 ​ $ 18,200 ​ ADDF On March 24, 2022, the Company entered into a contract with the Alzheimer’s Drug Discovery Foundation (ADDF) (the ADDF Grant). ADDF is a charitable venture philanthropy entity that has granted the Company funding in support of certain activities for the development of an in vitro diagnostic (IVD) test for early detection of Alzheimer's disease. The ADDF Grant, which has a total funding value of $ 2.3 million, restricts the Company’s use of the granted funds to be used solely for activities related to the Alzheimer’s diagnostic test development project. Contract funding is subject to achievement of these pre-defined milestones and the contract period runs through June 2024. The Company recognizes revenue over time as the related services are performed. As of December 31, 2022, the Company had received $ 1.3 million of the total funding value of $ 2.3 million under the ADDF Grant. During the year ended December 31, 2022, the Company recognized $ 0.6 million in grant revenue and incurred $ 0.6 million in research and development expense related to the ADDF Grant. No such activities occurred in the years ended December 31, 2021 and 2020. 4. 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. Activity related to the allowance for credit losses was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 ​ 2021 ​ 2020 Balance at January 1 $ 419 ​ $ 370 ​ $ 162 Provision charges ​ 752 ​ ​ 213 ​ ​ 493 Deductions ​ ( 1,053 ) ​ ​ ( 164 ) ​ ​ ( 285 ) Balance at December 31 $ 118 ​ $ 419 ​ $ 370 F-21 Table of Contents ​ ​ 5. 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. As of December 31, 2022 and 2021, 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 years ended December 31, 2022 and 2021, the Company recognized no revenue, respectively, within collaboration and license revenue related to the initial license fee under the Abbott License Agreement. ​ 6. Inventory Inventory consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2021 Raw materials ​ $ 5,509 ​ $ 7,892 Work in process ​ 3,362 ​ 4,923 Finished goods ​ 7,915 ​ 9,375 Total ​ $ 16,786 ​ $ 22,190 ​ Inventory comprises commercial instruments, assays, and the materials required to manufacture assays. F-22 Table of Contents 7. Property and equipment Property and equipment consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2021 Laboratory and manufacturing equipment ​ $ 11,806 ​ $ 9,742 Office furniture and equipment ​ 1,798 ​ 1,617 Computers and software ​ 3,831 ​ 3,893 Leasehold improvements ​ 13,688 ​ 10,413 Total cost ​ $ 31,123 ​ $ 25,665 Less: accumulated depreciation ​ ( 10,961 ) ​ ( 7,705 ) Property and equipment, net ​ $ 20,162 ​ $ 17,960 ​ The Company incurred depreciation expense of $ 3.5 million, $ 2.8 million and $ 2.2 million for the years ended December 31, 2022, 2021, and 2020, respectively. The Company has instruments included in laboratory and manufacturing equipment, which are used internally by the Company. As of December 31, 2022, the laboratory and manufacturing equipment balance includes $ 7.5 million of cost and $ 3.2 million of accumulated depreciation related to these instruments. 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. ​ For the year ended December 31, 2022, the Company recorded $ 4.3 million of impairment expense to leasehold improvements and other assets associated with the Bedford, Massachusetts leased office and laboratory space not being utilized by the Company. The Company decided not to utilize the space as part of the Restructuring Plan and intends to sublease the vacant space to recover a portion of the total cost. The Company’s decision to not utilize, and sublease, the leased asset triggered an impairment event. The impairment testing deemed all assets associated with the leased assets as one asset group. The impairment analysis evaluated the present value of net cash flows under the original lease and the estimated cash flows under the sublease to identify the impairment amount. The impairment assessment considered all industry and economic factors such as rental rates, interest rates and recent real estate activities to estimate the net cash flows analysis and impairment amount. ​ The Company recorded $ 1.1 million of impairment expense to Computers and software for the year ended December 31, 2022. A change in the scope of the intended use of these assets was considered to be the triggering event for the impairment assessment and expense. ​ No such impairment expenses were recognized for the years ended December 31, 2021 and 2020. ​ 8. Other accrued expenses Other accrued expenses consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2021 Royalties $ 815 ​ $ 1,250 Professional and outside services ​ 1,409 ​ ​ 2,126 Tax liabilities 172 ​ 430 Other 2,351 ​ 2,680 Total accrued expenses $ 4,747 ​ $ 6,486 ​ ​ F-23 Table of Contents 9. Income taxes The following table presents the components of loss before income taxes (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 2020 United States ​ $ ( 89,590 ) ​ $ ( 56,554 ) ​ $ ( 29,896 ) Foreign ​ ( 7,045 ) ​ ( 1,170 ) ​ ( 2,010 ) Total loss before income taxes ​ $ ( 96,635 ) ​ $ ( 57,724 ) ​ $ ( 31,906 ) ​ The following table summarizes income tax (expense) benefit (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 Current: ​ ​ ​ ​ ​ ​ ​ ​ United States ​ ​ ​ ​ ​ ​ ​ ​ Federal $ — $ — $ — State ​ ( 77 ) ​ ​ ( 30 ) ​ ​ ( 13 ) Foreign ​ ( 368 ) ​ ​ ( 342 ) ​ ​ ( 102 ) Total current income tax provision ​ ( 445 ) ​ ​ ( 372 ) ​ ​ ( 115 ) Deferred ​ ​ ​ ​ ​ ​ ​ ​ United States ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ 10 ​ ​ 5 ​ ​ ( 8 ) State ​ 13 ​ ​ ( 6 ) ​ ​ ( 3 ) Foreign ​ 357 ​ ​ 409 ​ ​ 502 Total deferred income tax benefit ​ 380 ​ ​ 408 ​ ​ 491 Total income tax (expense) benefit $ ( 65 ) ​ $ 36 ​ $ 376 ​ A reconciliation of the federal statutory income tax rate to the effective tax rate is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 2021 2020 Federal statutory income tax rate 21.0 % 21.0 % 21.0 % Foreign tax rate differential — % — % 0.30 % State taxes, net of federal benefit 2.7 % 6.5 % 2.5 % Tax credits 1.4 % 2.0 % 1.6 % Share-based compensation ( 2.5 ) % 7.4 % 5.2 % Permanent items ( 0.3 ) % ( 1.8 ) % ( 0.4 ) % Deferred tax rate change — % 0.2 % 0.3 % Change in valuation allowance ( 20.8 ) % ( 34.8 ) % ( 29.7 ) % Impairment of goodwill ( 1.7 ) % — % — % Other 0.0 % ( 0.4 ) % 0.4 % Effective income tax rate ( 0.2 ) % 0.1 % 1.2 % ​ The effective income tax rate 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. 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, ​ 2022 2021 Deferred tax assets: ​ ​ Net operating loss carryforwards $ 78,191 ​ $ 67,543 Tax credits 7,407 ​ 6,113 Deferred revenue ​ 2,385 ​ ​ 1,862 Amortization ​ 847 ​ ​ 962 Stock-based compensation 2,773 ​ 3,138 Inventory ​ 1,507 ​ ​ 686 Capitalized R&D Costs ​ 5,680 ​ ​ — Lease liability ​ 10,856 ​ ​ 5,464 Other deferred tax assets ​ 1,370 ​ ​ 2,340 Total deferred tax assets 111,016 ​ 88,108 Less: valuation allowances ​ ( 103,243 ) ​ ​ ( 83,121 ) Net deferred tax assets ​ 7,773 ​ ​ 4,987 Deferred tax liabilities: ​ ​ ​ ​ ​ Right-of-Use Assets ​ ( 5,219 ) ​ ​ ( 2,867 ) Depreciation ​ ( 2,244 ) ​ ​ ( 1,752 ) Amortization acquired intangibles ​ ( 1,570 ) ​ ​ ( 2,208 ) Goodwill ​ — ​ ​ ( 66 ) Other deferred tax liabilities ​ ( 209 ) ​ ​ ( 129 ) Net deferred tax (liability) asset $ ( 1,469 ) ​ $ ( 2,035 ) ​ The Company’s change in its valuation allowance account with respect to the deferred tax asset is as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ 2022 2021 Balance, beginning of year $ 83,121 ​ $ 63,609 Change in valuation allowance ​ 20,122 ​ ​ 19,512 Balance, end of year $ 103,243 ​ $ 83,121 ​ The valuation allowance increased during the year ended December 31, 2022 primarily as a result of the U.S. operating losses incurred 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, 2022, the Company maintains a full valuation allowance against its worldwide net deferred tax assets. As of December 31, 2022, the Company had U.S. federal NOLs of approximately $ 309.7 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 $ 201.2 million do not expire. As of December 31, 2022, the Company had $ 207.4 million of state NOLs, approximately $ 197.4 million expire at various dates through 2042, and certain state NOLs of approximately $ 10.0 million do not expire. As of December 31, 2022, the Company had U.S. federal tax credit carryforwards of approximately $ 5.8 million that expire at various dates through 2042. As of December 31, 2022, the Company had U.S. state tax credit carryforwards of approximately $ 2.0 million that expire at various dates through 2037. F-25 Table of Contents 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 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, 2022, 2021, and 2020, 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, 2022, the Company is generally no longer subject to examination by taxing authorities in the United States for years prior to 2019. However, NOLs and tax 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 2013 onward. As of December 31, 2022, the Company’s foreign subsidiaries had immaterial undistributed earnings and the tax payable on the earnings that are indefinitely reinvested would be immaterial. 10. Stock-Based Compensation Stock-based compensation Stock-based compensation expense for all stock awards consists of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2022 2021 2020 Cost of product revenue $ 608 ​ $ 471 ​ $ 189 Cost of service and other revenue 819 ​ 403 ​ 311 Research and development 1,639 ​ 1,807 ​ 1,129 Selling, general, and administrative 12,376 ​ 13,294 ​ 8,470 Total stock-based compensation $ 15,442 ​ $ 15,975 ​ $ 10,099 ​ At December 31, 2022, there was $ 33.9 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. F-26 Table of Contents 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 Company’s IPO, the Company terminated the 2007 Plan. As of December 31, 2022, 207,464 shares were outstanding under the 2007 Plan, and no shares are 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, 2022, 3,168,278 shares were outstanding and there were 1,847,643 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: (i) 4 % of the number of shares of common stock outstanding as of such date and (ii) an amount determined by the Company’s Board of Directors or Compensation Committee. On January 3, 2023, the number of shares of common stock available for issuance under the 2017 plan was increased by 1,488,696 shares in accordance with the 2017 Plan’s evergreen provision. In December 2017, the Company adopted the 2017 Employee Stock Purchase Plan (the 2017 ESPP). As of December 31, 2019, the 2017 ESPP allowed for the issuance of up to 612,572 shares of common stock. As of December 31, 2022, 1,447,467 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: (i) 1 % of the number of shares of common stock outstanding on the last day of the immediately preceding fiscal year and (ii) an amount determined by the Company’s Board of Directors or Compensation Committee. On January 3, 2023, the number of shares of common stock available for issuance under the 2017 ESPP was increased by 372,174 shares in accordance with the 2017 ESPP’s evergreen 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. Stock options Under the 2017 Plan, stock options may not be granted with exercise prices of less than fair market value on the date of the grant. Options generally vest ratably over a four-year period with 25 % vesting on the first anniversary and the remaining 75 % vesting ratably on a monthly basis over the remaining three years . These options expire ten years after the grant date. Option activity is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average ​ Remaining contractual ​ Aggregate intrinsic value ​ Options exercise price life (in years) (in thousands) Outstanding at December 31, 2021 2,204,813 $ 25.36 ​ 6.8 ​ $ 44,813 Granted 1,507,452 ​ $ 18.07 ​ ​ ​ ​ ​ Exercised ( 243,792 ) ​ $ 5.10 ​ ​ ​ ​ ​ Cancelled ( 1,280,825 ) ​ $ 28.63 ​ ​ ​ ​ ​ Outstanding at December 31, 2022 2,187,648 ​ $ 20.69 ​ 8.1 ​ ​ 4,273 Exercisable at December 31, 2022 820,868 ​ $ 22.92 ​ 5.8 ​ ​ 1,566 Vested and expected to vest at December 31, 2022 2,187,648 ​ $ 20.69 ​ 8.1 ​ ​ 4,273 F-27 Table of Contents ​ 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, 2021 529,871 $ 49.32 ​ 9.7 ​ $ 22,467 Granted 1,273,807 ​ $ 18.32 ​ ​ ​ ​ ​ Vested ( 200,078 ) ​ $ 48.93 ​ ​ ​ ​ ​ Cancelled ( 415,506 ) ​ $ 34.94 ​ ​ ​ ​ ​ Unvested RSUs as of December 31, 2022 1,188,094 ​ ​ 21.18 ​ 9.6 ​ $ 16,455 Expected to convert at December 31, 2022 1,188,094 ​ $ 21.18 ​ ​ ​ $ 16,455 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 11. Earnings (Loss) Per Share The following table presents the computation of basic and diluted earnings per share: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 ​ (in thousands, except share and per share data) Numerator: ​ ​ ​ ​ ​ Net loss attributable to Quanterix Corporation ($ 96,700 ) ​ ($ 57,688 ) ​ ($ 31,530 ) ​ ​ ​ ​ ​ ​ Denominator: ​ ​ ​ ​ ​ Weighted average shares of common stock outstanding, basic and diluted 36,990,965 ​ 35,997,473 ​ 29,589,132 ​ ​ ​ ​ ​ ​ Net loss per share attributable to Quanterix Corporation, basic and diluted ($ 2.61 ) ​ ($ 1.60 ) ​ ($ 1.07 ) ​ In periods when the Company is in a net loss position, dilutive securities are excluded from the computation of diluted earnings per share because their inclusion would have an anti-dilutive effect. Thus, basic net loss per share is the same as diluted net loss per share. The following common share equivalents have been excluded from the calculation of diluted net loss per share: ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ 2022 2021 2020 Unvested restricted common stock and restricted stock units 701,707 531,473 518,387 Outstanding stock options 446,180 2,304,543 2,494,045 Outstanding common stock warrants — — 10,000 ​ ​ 12. Leases Bedford Lease On January 28, 2022, the Company executed a lease for 85,800 square feet of office and laboratory space in Bedford, Massachusetts. The lease commencement date was February 1, 2022, when the Company gained access to the underlying facilities. The Company has negotiated a tenant improvement allowance with the landlord which will offset a portion of the Company’s construction costs. The Company has assessed whether improvements made to the premises are landlord-owned or company-owned, with payments made by the Company for landlord-owned assets accounted for as lease incentives. The initial term of the lease’s payment schedule is eight years and nine months beginning on May 1, 2022. The Company has the option to extend the lease for two additional five-year periods. F-28 Table of Contents In applying the ASC 842 transition guidance, the Bedford Lease has been assessed as an operating lease and the Company recorded ROU assets of $ 18.2 million and lease liability of $ 23.7 million on the effective date. The difference between the ROU and the lease liability was driven by the lease obligation incentive of $ 5.5 million. As part of the Restructuring Plan, the Company decided not to utilize these facilities as part of its own operations and intends to sublease the vacant space to recover a portion of the total cost. The Company’s decision to not utilize, and sublease, the leased asset triggered an impairment event. The impairment testing deemed all assets associated with the leased assets as one asset group. The impairment analysis evaluated the present value of net cash flows under the original lease and the estimated cash flows under the sublease to identify the impairment amount. The impairment assessment considered all industry and economic factors such as rental rates, interest rates and recent real estate activities to estimate the net cash flows analysis and impairment amount. ​ For the year ended December 31, 2022, the Company recorded an impairment of $ 12.0 million to the right-of-use assets related to the Bedford facilities. ​ No such impairment expenses were recognized for the years ended December 31, 2021 and 2020. ​ Summary of all lease costs recognized under ASC 842 Total operating lease costs were $ 8.9 million, which includes $ 3.4 million of short term and variable lease costs for the year ended December 31, 2022. Total operating lease costs were $ 5.4 million and $ 4.8 million for the years ended December 31, 2021 and 2020, respectively. The fixed lease costs were $ 5.5 million, $ 5.4 million and $ 4.8 million for the years ended December 31, 2022, 2021 and 2020, respectively. Short-term lease costs and variable lease costs incurred by the Company for the years ended December 31, 2021 and 2020 were considered immaterial. Refer to table below for additional information related to operating leases under ASC 842: ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, Operating leases (in thousands) ​ 2022 ​ 2021 Supplemental balance sheet information: ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (years) ​ ​ 7.8 ​ ​ 8.6 Weighted average discount rate ​ ​ 7.83 % ​ ​ 9.73 % ​ ​ ​ ​ ​ ​ ​ Supplemental cash flow information: ​ ​ ​ ​ ​ ​ Operating cash flows used for operating leases ​ $ 6,539 ​ $ 3,388 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Future minimum commitments under ASC 842 under the Company’s operating leases in effect at December 31, 2022 were as follows: ​ ​ ​ ​ Maturity of lease liabilities (in thousands) ​ As of December 31, 2022 2023 ​ $ 6,707 2024 ​ ​ 7,064 2025 ​ ​ 7,228 2026 ​ ​ 7,408 2027 ​ ​ 7,641 thereafter ​ ​ 23,621 Total lease payments ​ $ 59,669 Less: imputed interest and lease incentive reimbursements ​ ​ 15,565 Total operating lease liabilities ​ $ 44,104 ​ ​ F-29 Table of Contents 13. Commitments and contingencies Purchase Commitments Stratec During the year ended December 31, 2022, the Company entered into a supply agreement (the Stratec Supply Agreement) with Stratec Consumables GmBH (Stratec) to order discs used in manufacturing the Simoa HD-X instrument. As part of the Stratec Supply Agreement, the Company agreed to purchase a total of 375,000 discs to be shipped at various points starting in 2022 and continuing through 2024 at an agreed purchase price per disc. In 2022, under the Stratec Supply Agreement, Stratec shipped 75,000 discs to the Company. The Company recorded cost of product revenue related to this shipment of $ 0.5 million for the year ended December 31, 2022. No such activities existed for the years ended December 31, 2021 and 2020. Additionally, per the Stratec Supply Agreement, during the years ended December 31, 2023 and 2024, Stratec is required to ship 220,000 and 80,000 discs, respectively, to the Company. In the years ending December 31, 2023 and 2024, the Company expects to record cost of product revenue of $ 1.6 million and $ 0.6 million, respectively, related to those shipments. As of December 31, 2022, the Company also has $ 0.9 million of open purchase orders with Stratec. Other Purchase Commitments The Company purchases substantial amounts of raw materials for manufacturing operations under annual and multi-year agreements, some of which have minimum quantity requirements. Additionally, the Company enters into annual agreements for other parts of its operations. The Company has total purchase commitments for the year ended December 31, 2022, of $ 3.1 million, most of which the Company expects to incur in the year ending December 31, 2023. 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, 2022, 2021, and 2020, the Company recorded royalty expense of $ 1.4 million, $ 1.6 million and $ 1.1 million, respectively, related to Tufts. This royalty expense is recorded 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), refer to Note 5 for additional details. 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. ​ F-30 Table of Contents 14. Restructuring and Other Charges Following a strategic review and assessment of the Company’s operations and cost structure, on August 8, 2022, the Company announced a plan of restructuring and strategic re-alignment (the Restructuring Plan). As part of the Restructuring Plan, the Company began an assay redevelopment program with the ultimate objective of improving its ability to manufacture and deliver high-quality assays at scale. In accordance with the Restructuring Plan, the Company implemented a workforce reduction, which was substantially completed by the end of the third quarter of 2022. The Company recorded charges during the year ended December 31, 2022, consisting of one-time termination benefits for employee severance, benefits and related costs, all of which were cash expenditures. The following shows the number of positions by function and by location eliminated in connection with the Restructuring Plan: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America ​ EMEA ​ Asia Pacific ​ Total Cost of goods sold 21 ​ — ​ — ​ 21 Research and development 34 ​ 1 ​ — ​ 35 Selling, general and administrative 50 ​ 9 ​ 4 ​ 63 Total headcount 105 ​ 10 ​ 4 ​ 119 ​ As part of the Restructuring Plan, the Company also performed an assessment of impairment for long-lived assets, including right-of-use assets, and recorded an impairment charge of $ 17.4 million. The impairment expense includes $ 16.3 million associated with the right-of-use and property and equipment at the Bedford facilities and $ 1.1 million for software costs related to projects that have been rationalized as part of the Restructuring Plan. Refer to Note 7 and Note 12 for further information. The following table presents the restructuring reserve and provision activity for the year ended December 31, 2022 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Severance and Employee Benefit Costs ​ Other Restructuring Charges ​ Total Balance at January 1, 2022 $ — ​ $ — ​ $ — Charges ​ 3,634 ​ ​ 121 ​ ​ 3,755 Cash payments ​ ( 3,288 ) ​ ​ ( 121 ) ​ ​ ( 3,409 ) Foreign exchange ​ ( 18 ) ​ ​ — ​ ​ ( 18 ) Balance at December 31, 2022 $ 328 ​ $ — ​ $ 328 ​ No such restructuring activities existed for the years ended December 31, 2021 and 2020. ​ ​ 15. 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 the term loan was variable based on the greater of 8 % or 8 % plus the prime rate less 5.25 %. Interest was 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 contained prepayment penalties and an end of term charge. Fees incurred upon execution of the agreements, and the fair value of warrants on F-31 Table of Contents 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. The Company has not executed any subsequent loan agreements and there were no outstanding loan balances during the year ended December 31, 2022. 16. 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, 2022, 2021, and 2020, the Company made contributions of $ 1.2 million, $ 1.1 million, and $ 0.7 million, respectively. 17. Goodwill and intangible assets During the third quarter of 2022, the Company identified certain indicators of impairment, including the significant decline in the Company’s stock price, actions taken under the Restructuring Plan and the reduction of forecasted sales and profitability. As a result, the Company performed an interim goodwill impairment test. It was determined that the Company’s goodwill was impaired as the carrying amount of the Company’s sole reporting unit exceeded the estimated fair value. The Company concluded that the entire goodwill balance was impaired and recognized a non-cash impairment charge during the third quarter of 2022. ​ The changes in the carrying amount of goodwill are as follows (in thousands): ​ ​ ​ ​ ​ Goodwill Balance as of December 31, 2021 $ 9,632 Impairment losses ( 8,220 ) Foreign exchange adjustments ​ ( 1,412 ) Balance as of December 31, 2022 $ — ​ Acquired intangible assets, principally originating from the acquisition of Uman, consist of the following (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ ​ ​ 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 ​ $ ( 4,763 ) ​ $ ( 1,433 ) ​ $ 6,804 ​ 5.0 Developed technology 7 ​ ​ 1,650 ​ ​ ( 1,458 ) ​ ​ — ​ ​ 192 ​ 2.1 Customer relationships 8.5 - 10 ​ 1,360 ​ ( 938 ) ​ ​ ( 12 ) ​ 410 ​ 5.1 Non-compete agreements 5.5 ​ ​ 340 ​ ​ ( 193 ) ​ ​ ( 37 ) ​ ​ 110 ​ 2.0 Trade names 3 ​ 50 ​ ( 50 ) ​ ​ — ​ — ​ — Total ​ ​ $ 16,400 ​ $ ( 7,402 ) ​ $ ( 1,482 ) ​ $ 7,516 ​ ​ ​ F-32 Table of Contents ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 ​ ​ ​ The Company recorded amortization expense of $ 1.8 million, $ 2.0 million, and $ 2.1 million for the years ended December 31, 2022, 2021, and 2020, 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. Future estimated amortization expense of acquired intangible assets as of December 31, 2022 is as follows (amounts in thousands): ​ ​ ​ ​ ​ As of December 31, 2022 2023 $ 1,665 2024 ​ 1,584 2025 ​ 1,447 2026 ​ 1,420 2027 ​ 1,398 Thereafter ​ 2 Total amortization expense $ 7,516 ​ ​ 18. Related party transactions As described in Note 13, 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 one of the Company’s directors was affiliated with Tufts. During the years ended December 31, 2022, 2021, and 2020, the Company recorded royalty expense of $ 1.4 million, $ 1.6 million and $ 1.1 million, respectively, related to Tufts. This royalty expense is recorded 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, refer to 5 for additional details. One of the Company’s directors is affiliated with Harvard University and Mass General Brigham. Revenue recorded from sales to Harvard University and its affiliates and to Mass General Brigham and its affiliates totaled $ 0.7 million, $ 0.2 million, $ 0.1 million for the years ended December 31, 2022, 2021, and 2020 respectively. The Company recorded cost of goods sold of $ 0.1 million for the year ended December 31, 2022 related to Harvard University and its affiliates and to Mass General Brigham and its affiliates, with immaterial cost of goods sold recorded for years ended December 31, 2021 and 2020. The Company also incurred research and development expenses of $ 0.6 million with Harvard University and its affiliates for the year ended December 31, 2022, with immaterial research and development expenses incurred for years ended December 31, 2021 and 2020. The Company had $ 0.1 million and $ 0.2 million in accounts receivable from Harvard University and its affiliates and Mass General Brigham and its affiliates at December 31, 2022 and 2021, respectively. Deferred revenue from Harvard University and its affiliates and Mass General Brigham and its affiliates was $ 0.1 million at both December 31, 2022 and 2021. On May 26, 2022, the Company entered into an agreement (the UltraDx Agreement) with UltraDx Limited (UltraDx), a new company formed by ARCH Venture Partners (ARCH). Under the UltraDx Agreement, the Company F-33 Table of Contents will supply HD-X instruments (both fully assembled and disassembled) as well as assays and assay components to UltraDx, and UltraDx has the non-exclusive right to seek Chinese regulatory approval of and to commercialize the HD-X instrument and related assays in the Chinese neurological in vitro diagnostic market. The Company has determined that UltraDx is a related party because one of the Company’s directors is affiliated with ARCH and UltraDx. Under the terms of the UltraDx Agreement, the Company shipped a total of ten fully assembled and disassembled HD-X instruments to UltraDx on June 30, 2022 at a purchase price of approximately $ 1.9 million. The Company recognized revenue on these shipments upon receipt of payment during the year ended December 31, 2022. No such activities occurred in the years ended December 31, 2021 and 2020. ​ ​ ​ ​ ​ F-34