Quanterix (QTRX) 10-Q/A 2024 Q1 Quarterly report (amended)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

_________________________________________________________________

FORM 10-Q/A

(Amendment No. 1)

_________________________________________________________________

(Mark One)

x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2024

OR

o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from          to          .

Commission File Number: 001-38319

_________________________________________________________________

QUANTERIX CORPORATION

(Exact name of registrant as specified in its charter)

_________________________________________________________________

Delaware	20-8957988
(State or other jurisdiction of incorporation or organization)	(IRS Employer Identification No.)
900 Middlesex Turnpike
Billerica, MA	01821
(Address of principal executive offices)	(Zip Code)

(617) 301-9400

(Registrant’s telephone number, including area code)

_________________________________________________________________

Securities registered pursuant to Section 12(b) of the Exchange Act:

Title of each class:	Trading Symbol(s)	Name of each exchange on which registered:
Common Stock, $0.001 par value per share	QTRX	The Nasdaq Global Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes  o      No  x

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).     Yes  x      No  o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	x	Accelerated filer	o
Non-accelerated filer	o	Smaller reporting company	o
		Emerging growth company	o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). o   Yes   x   No

As of May 2, 2024, the registrant had 38,270,088 shares of common stock outstanding.

EXPLANATORY NOTE

Overview

Quanterix Corporation (“it”, “Quanterix” or the “Company”) is filing this Amendment No. 1 on Form 10-Q/A (the “Amended Report”) to amend and restate certain items in its Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2024, originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on May 8, 2024 (the “Original Report”), in order to reflect the effects of the restatement of the financial statements included therein (the “Restatement”). This Amended Report includes the Company’s restated unaudited Consolidated Financial Statements as of March 31, 2024, for the quarterly periods ended March 31, 2024 and 2023, and the Company's restated audited Consolidated Financial Statements as of December 31, 2023 to correct an error related to its inventory valuation and to correct certain other unrelated errors.

On December 23, 2024, the Company also filed Amendment No. 1 to its Annual Report on Form 10-K/A for the fiscal year ended December 31, 2023, originally filed with the SEC on February 29, 2024 (the “Amended Annual Report”), to amend and restate certain items in such report and to include the Company’s restated audited Consolidated Financial Statements as of December 31, 2023 and 2022 and for each of the three years in the period ended December, 31 2023 and its unaudited Consolidated Financial Statements for all of the quarterly and year-to-date (as applicable) periods of 2023 and 2022.

In addition, the Company is separately filing an amendment to its Quarterly Report on Form 10-Q/A for the quarterly period ended June 30, 2024, originally filed with the SEC on August 8, 2024 (collectively with this Amended Report and the Amended Annual Report, the “Amended Filings”), which includes restated unaudited Consolidated Financial Statements for the quarterly and year-to-date periods of 2024 and 2023 covered by such report.

Restatement Background

As previously disclosed by the Company in its Current Report on Form 8-K filed with the SEC on November 12, 2024, in connection with its efforts to remediate a material weakness in its internal control over financial reporting relating to the operating effectiveness of internal controls associated with the accounting for inventory valuation, and while performing closing procedures for the third quarter of 2024, management identified an error related to the capitalization of labor and overhead costs in the Company's inventory balances in prior periods (the “Misstatement”). The error was not caused by any override of controls, misconduct, or fraud. The correction of the Misstatement impacts the previously reported amounts of inventory, cost of product revenue, net loss per common share, and all related financial statement subtotals and totals. In addition to correcting the Misstatement, the Amended Filings also reflect adjustments to correct unrelated errors to other financial statement line items identified by the Company in prior periods which include, but are not limited to, adjustments to property and equipment, accrued compensation and benefits, and operating expenses.

Refer to Note 1 - Restatement of Financial Statements in the Notes to Consolidated Financial Statements for more information related to the Restatement, including the impact on the Company’s Consolidated Financial Statements.

Internal Control Considerations

In connection with preparing this Amended Report, management has updated its evaluation of the effectiveness of its internal control over financial reporting as of March 31, 2024, as further described in Part I, Item 4. “Controls and Procedures” of this Amended Report. Consistent with the conclusion in Part II, Item 9A. “Controls and Procedures” of the Amended Annual Report, management continued to conclude that its internal control over financial reporting and disclosure controls and procedures were not effective as of March 31, 2024 due to the previously identified material weaknesses in its internal control over financial reporting, including that the material weakness in the controls relating to the operating effectiveness over accounting for inventory valuation should reflect the additional internal control design deficiency associated with the Misstatement.

Items Amended in this Amended Report

This Amended Report amends and restates the sections of the Original Report listed below, with modifications as necessary to reflect the Restatement. No attempt has been made in this Amended Report to update other disclosures in the Original Report, except as required to reflect the effects of the Restatement in the following amended items:

2

•Note Regarding Forward-Looking Statements

•Part I, Item 1. Financial Statements (Unaudited)

•Part I, Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

•Part I, Item 4. Controls and Procedures

•Part II, Item 6. Exhibits

Except as described above, this Amended Report does not amend, update, or change any other disclosures in the Original Report. Among other things, except as related to the Restatement, forward looking statements made in the Original Report have not been revised to reflect events that occurred or facts that became known to the Company after the filing of the Original Report, and such forward looking statements should be read in their historical context. As such, this Amended Report speaks only as of the date the Original Report was filed, and the Company has not undertaken herein to amend, supplement, or update any information contained in the Original Report to give effect to any subsequent events. Accordingly, this Amended Report should be read in conjunction with the Original Report, including any other filings with the SEC.

In addition, as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), new certifications by the Company’s Chief Executive Officer (as principal executive officer) and Chief Financial Officer (as principal financial officer) are filed herewith as Exhibits 31.1, 31.2 and 32.1 to this Amendment pursuant to Rule 13a-14(a) of the Exchange Act and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. 1350).

3

TQUANTERIX CORPORATION

INDEX TO FORM 10-Q/A

	Page
Note Regarding Forward-Looking Statements	5
PART I — FINANCIAL INFORMATION
Item 1. Financial Statements (Unaudited) (As Restated)	6
Consolidated Balance Sheets as of March 31, 2024 and December 31, 2023 (As Restated)	6
Consolidated Statements of Operations for the three months ended March 31, 2024 and 2023 (As Restated)	7
Consolidated Statements of Comprehensive Loss for the three months ended March 31, 2024 and 2023 (As Restated)	8
Consolidated Statements of Stockholders’ Equity for the three months ended March 31, 2024 and 2023 (As Restated)	9
Consolidated Statements of Cash Flows for the three months ended March 31, 2024 and 2023 (As Restated)	10
Notes to Consolidated Financial Statements (As Restated)	11
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations (As Restated)	33
Item 4. Controls and Procedures (As Restated)	39
PART II — OTHER INFORMATION
Item 6. Exhibits (As Restated)	42
Signatures	43

4

Unless the context otherwise requires, the terms “Quanterix,” the “Company,” “we,” “it,” “us,” and “our” in this Amended Report refer to Quanterix Corporation and its consolidated subsidiaries.

NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Amended Report contains forward-looking statements (within the meaning of the U.S. Private Securities Litigation Reform Act of 1995) that involve risks and uncertainties. All statements other than statements of historical facts contained in this Amended Report are forward-looking statements. In some cases, forward-looking statements can be identified by words such as “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “seek,” “should,” “target,” “will,” “would,” or the negative of these words, or other comparable terminology. These forward-looking statements include, but are not limited to, statements related to our financial performance and the effects of the Restatement, and are subject to a number of risks, uncertainties, and assumptions, including those further described elsewhere in this Amended Report, in the section titled “Part II, Item 1A. Risk Factors” of the Original Report, in the section titled “Part I, Item 1A. Risk Factors” of the Amended Annual Report, or in other filings that we make with the SEC. Moreover, we operate in a very competitive and rapidly changing environment, and new risks emerge from time to time. It is not possible for us to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties, and assumptions, the forward-looking events and circumstances discussed in this Amended Report may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements.

Readers should not rely upon forward-looking statements as predictions of future events. Although we believe that the expectations reflected in any forward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance, or events and circumstances reflected in forward-looking statements will be achieved or occur. We undertake no obligation to update publicly any forward-looking statements for any reason after the date of this Amended Report to conform these statements to new information, actual results, or to changes in our expectations, except as required by law.

Readers should read this Amended Report and any documents referenced herein that we have filed with the SEC as exhibits to this Amended Report with the understanding that our actual future results, levels of activity, performance, and events and circumstances may be materially different from what we expect.

Service Marks, Trademarks and Trade Names

“Quanterix,” “Simoa,” “Simoa HD-X,” “Simoa HD-1,” “SR-X,” “SP-X”, “HD-X”, “LucentAD,” “Lucent Diagnostics,” and our logo are our trademarks. All other service marks, trademarks, and trade names appearing in this Amended Report are the property of their respective owners. We do not intend our use or display of other companies’ trade names, trademarks, or service marks to imply a relationship with, or endorsement or sponsorship of us, by these other companies.

5

PART I — FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS (UNAUDITED)

QUANTERIX CORPORATION

CONSOLIDATED BALANCE SHEETS

(amounts in thousands, except per share data)

	March 31, 2024		December 31, 2023
	(As Restated)		(As Restated)
ASSETS
Current assets:
Cash and cash equivalents	$	45,281	$	174,422
Marketable securities	256,640		146,902
Accounts receivable, net of allowance for expected credit losses	29,276		25,414
Inventory	28,634		26,123
Prepaid expenses and other current assets	9,521		9,234
Total current assets	369,352		382,095
Restricted cash	2,605		2,604
Property and equipment, net	17,492		17,926
Intangible assets, net	5,339		6,034
Operating lease right-of-use assets	17,748		18,251
Other non-current assets	1,669		1,657
Total assets	$	414,205	$	428,567
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Accounts payable	$	3,979	$	5,048
Accrued compensation and benefits	7,196		14,170
Accrued expenses and other current liabilities	6,982		6,055
Deferred revenue	10,234		9,468
Operating lease liabilities	4,366		4,241
Total current liabilities	32,757		38,982
Deferred revenue, net of current portion	933		1,227
Operating lease liabilities, net of current portion	36,084		37,223
Other non-current liabilities	1,053		1,177
Total liabilities	70,827		78,609
Commitments and contingencies (Note 13)
Stockholders’ equity:
Common stock, $0.001 par value per share:
Authorized: 120,000 shares; issued and outstanding: 38,288 and 38,014 shares at March 31, 2024 and December 31, 2023, respectively	38		38
Additional paid-in capital	789,006		783,142
Accumulated other comprehensive loss	(2,953)		(1,672)
Accumulated deficit	(442,713)		(431,550)
Total stockholders’ equity	343,378		349,958
Total liabilities and stockholders’ equity	$	414,205	$	428,567

The accompanying notes are an integral part of these Consolidated Financial Statements.

6

QUANTERIX CORPORATION

CONSOLIDATED STATEMENTS OF OPERATIONS

(amounts in thousands, except per share data)

	Three Months Ended March 31,
	2024		2023
	(As Restated)		(As Restated)
Revenues:
Product revenue	$	19,670	$	19,360
Service and other revenue	11,967		8,506
Collaboration and license revenue	155		368
Grant revenue	274		222
Total revenues	32,066		28,456
Costs of goods sold and services:
Cost of product revenue	8,237		7,879
Cost of service and other revenue	5,281		4,584
Total costs of goods sold and services	13,518		12,463
Gross profit	18,548		15,993
Operating expenses:
Research and development	6,742		4,987
Selling, general and administrative	26,039		20,784
Other lease costs	924		800
Total operating expenses	33,705		26,571
Loss from operations	(15,157)		(10,578)
Interest income	3,948		3,449
Other income (expense), net	226		(5)
Loss before income taxes	(10,983)		(7,134)
Income tax expense	(180)		(140)
Net loss	$	(11,163)	$	(7,274)
Net loss per common share, basic and diluted	$	(0.29)	$	(0.19)
Weighted-average common shares outstanding, basic and diluted	38,126		37,327

The accompanying notes are an integral part of these Consolidated Financial Statements.

7

QUANTERIX CORPORATION

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

(amounts in thousands)

	Three Months Ended March 31,
	2024		2023
	(As Restated)		(As Restated)
Net loss	$	(11,163)	$	(7,274)
Other comprehensive income (loss), net of tax:
Unrealized losses on marketable securities	(607)		—
Foreign currency translation adjustment	(674)		42
Total other comprehensive income (loss)	(1,281)		42
Comprehensive loss	$	(12,444)	$	(7,232)

The accompanying notes are an integral part of these Consolidated Financial Statements.

8

QUANTERIX CORPORATION

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(amounts in thousands)

	Three Months Ended March 31, 2024
	Common Stock
	Shares	Amount		Additional paid-in capital		Accumulated other comprehensive income (loss)		Accumulated deficit		Total stockholders' equity
Balance at December 31, 2023 (As Restated)	38,014	$	38	$	783,142	$	(1,672)	$	(431,550)	$	349,958
Issuance of common stock under stock plans, including tax effects	274	—		599		—		—		599
Stock-based compensation expense	—	—		5,265		—		—		5,265
Unrealized loss on marketable securities, net of tax	—	—		—		(607)		—		(607)
Foreign currency translation adjustment	—	—		—		(674)		—		(674)
Net loss, as restated	—	—		—		—		(11,163)		(11,163)
Balance at March 31, 2024 (As Restated)	38,288	$	38	$	789,006	$	(2,953)	$	(442,713)	$	343,378
	Three Months Ended March 31, 2023
	Common Stock
	Shares	Amount		Additional paid-in capital		Accumulated other comprehensive income (loss)		Accumulated deficit		Total stockholders' equity
Balance at December 31, 2022 (As Restated)	37,280	$	37	$	763,629	$	(2,538)	$	(403,196)	$	357,932
Issuance of common stock under stock plans, including tax effects	144	—		551		—		—		551
Stock-based compensation expense, as restated	—	—		3,943		—		—		3,943
Foreign currency translation adjustment	—	—		—		42		—		42
Net loss, as restated	—	—		—		—		(7,274)		(7,274)
Balance at March 31, 2023 (As Restated)	37,424	$	37	$	768,123	$	(2,496)	$	(410,470)	$	355,194

The accompanying notes are an integral part of these Consolidated Financial Statements.

9

QUANTERIX CORPORATION

CONSOLIDATED STATEMENTS OF CASH FLOWS

(amounts in thousands)

	Three Months Ended March 31,
	2024		2023
	(As Restated)		(As Restated)
Cash flows from operating activities:
Net loss	$	(11,163)	$	(7,274)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,523		1,454
Credit losses on accounts receivable	176		178
Accretion of marketable securities	(1,657)		—
Operating lease right-of-use asset amortization	478		334
Stock-based compensation expense	5,265		3,943
Other operating activity	55		270
Changes in assets and liabilities:
Accounts receivable	(4,233)		(3,741)
Inventory	(2,531)		530
Prepaid expenses and other current assets	(281)		(422)
Other non-current assets	(33)		(33)
Accounts payable	(1,057)		(1,271)
Accrued compensation and benefits, accrued expenses, and other current liabilities	(6,200)		(5,809)
Deferred revenue	472		2,041
Operating lease liabilities	(988)		179
Other non-current liabilities	10		(203)
Net cash used in operating activities	(20,164)		(9,824)
Cash flows from investing activities:
Purchases of marketable securities	(137,889)		—
Proceeds from maturities of marketable securities	29,200		—
Purchases of property and equipment	(506)		(136)
Net cash used in investing activities	(109,195)		(136)
Cash flows from financing activities:
Proceeds from common stock issued under stock plans	2,037		564
Payments for employee taxes withheld on stock-based compensation awards	(1,438)		(13)
Net cash provided by financing activities	599		551
Net decrease in cash, cash equivalents, and restricted cash	(128,760)		(9,409)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(380)		24
Cash, cash equivalents, and restricted cash at beginning of period	177,026		341,337
Cash, cash equivalents, and restricted cash at end of period	$	47,886	$	331,952
Supplemental disclosure of cash flow information:
Cash paid for taxes	$	175	$	246
Purchases of property and equipment in accounts payable and accrued expenses	$	222	$	147

The accompanying notes are an integral part of these Consolidated Financial Statements.

10

QUANTERIX CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(unaudited)

Note 1. Restatement of Financial Statements

Subsequent to the issuance of Quanterix Corporation's (“Quanterix” or the “Company”) Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on May 8, 2024 (the “Original Report”), the Company identified an error related to the capitalization of labor and overhead costs in the Company's inventory balances (the “Misstatement”), which impacted the previously issued unaudited Consolidated Financial Statements as of March 31, 2024, for the quarterly periods ended March 31, 2024 and 2023, and the audited Consolidated Financial Statements as of December 31, 2023 (the “Restatement Periods”). In accordance with ASC 250 - Accounting Changes and Error Corrections, SEC Staff Accounting Bulletin (“SAB”) No. 99 - Materiality, and SAB No. 108 - Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements, management concluded the error was material to the Company’s financial statements and required restatement of the financial statements for the Restatement Periods (the “Restatement”). In connection with the Restatement, the Company is also correcting unrelated errors identified by the Company in prior periods.

Restatement Background

In connection with the Company's efforts to remediate a material weakness in its internal control over financial reporting relating to the operating effectiveness of internal controls associated with the accounting for inventory valuation, and while performing closing procedures for the third quarter of 2024, the Company identified the Misstatement. The correction of the Misstatement impacts the previously reported amounts of inventory, cost of product revenue, net loss per common share, and all related financial statement subtotals and totals. In addition, the correction of unrelated errors identified by the Company in prior periods includes, but is not limited to, adjustments to property and equipment, accrued compensation and benefits, and operating expenses (together with the Misstatement, the “Combined Misstatements”).

Impact of Restatement

The following tables present the impact of the Restatement to the specific line items presented in the previously reported unaudited Consolidated Financial Statements in all Restatement Periods. The amounts labeled "As Previously Reported" were derived from the Original Report. The amounts labeled “Adjustments” represent the impact of correcting the Combined Misstatements identified by the Company. The effects of the Restatement have been corrected in all impacted tables and footnotes throughout the Consolidated Financial Statements herein.

11

QUANTERIX CORPORATION

RESTATED CONSOLIDATED BALANCE SHEETS

(amounts in thousands, except per share data)

	As of March 31, 2024
	As Previously Reported		Adjustments		As Restated
ASSETS
Current assets:
Cash and cash equivalents	$	45,281	$	—	$	45,281
Marketable securities	256,640		—		256,640
Accounts receivable, net of allowance for expected credit losses	29,276		—		29,276
Inventory	26,015		2,619		28,634
Prepaid expenses and other current assets	9,551		(30)		9,521
Total current assets	366,763		2,589		369,352
Restricted cash	2,605		—		2,605
Property and equipment, net	17,492		—		17,492
Intangible assets, net	5,339		—		5,339
Operating lease right-of-use assets	17,748		—		17,748
Other non-current assets	1,802		(133)		1,669
Total assets	$	411,749	$	2,456	$	414,205
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Accounts payable	$	3,914	$	65	$	3,979
Accrued compensation and benefits	6,706		490		7,196
Accrued expenses and other current liabilities	7,021		(39)		6,982
Deferred revenue	10,234		—		10,234
Operating lease liabilities	4,366		—		4,366
Total current liabilities	32,241		516		32,757
Deferred revenue, net of current portion	933		—		933
Operating lease liabilities, net of current portion	36,084		—		36,084
Other non-current liabilities	1,053		—		1,053
Total liabilities	70,311		516		70,827
Commitments and contingencies (Note 13)
Stockholders’ equity:
Common stock, $0.001 par value per share:
Authorized: 120,000 shares; issued and outstanding: 38,288 shares at March 31, 2024	38		—		38
Additional paid-in capital	789,006		—		789,006
Accumulated other comprehensive loss	(3,038)		85		(2,953)
Accumulated deficit	(444,568)		1,855		(442,713)
Total stockholders’ equity	341,438		1,940		343,378
Total liabilities and stockholders’ equity	$	411,749	$	2,456	$	414,205

12

	As of December 31, 2023
	As Previously Reported		Adjustments		As Restated
ASSETS
Current assets:
Cash and cash equivalents	$	174,422	$	—	$	174,422
Marketable securities	146,902		—		146,902
Accounts receivable, net of allowance for expected credit losses	25,414		—		25,414
Inventory	22,365		3,758		26,123
Prepaid expenses and other current assets	9,291		(57)		9,234
Total current assets	378,394		3,701		382,095
Restricted cash	2,604		—		2,604
Property and equipment, net	17,926		—		17,926
Intangible assets, net	6,034		—		6,034
Operating lease right-of-use assets	18,251		—		18,251
Other non-current assets	1,802		(145)		1,657
Total assets	$	425,011	$	3,556	$	428,567
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Accounts payable	$	5,048	$	—	$	5,048
Accrued compensation and benefits	13,659		511		14,170
Accrued expenses and other current liabilities	6,041		14		6,055
Deferred revenue	9,468		—		9,468
Operating lease liabilities	4,241		—		4,241
Total current liabilities	38,457		525		38,982
Deferred revenue, net of current portion	1,227		—		1,227
Operating lease liabilities, net of current portion	37,223		—		37,223
Other non-current liabilities	1,177		—		1,177
Total liabilities	78,084		525		78,609
Commitments and contingencies (Note 13)
Stockholders’ equity:
Common stock, $0.001 par value per share:
Authorized: 120,000 shares; issued and outstanding: 38,014 shares at December 31, 2023	38		—		38
Additional paid-in capital	783,142		—		783,142
Accumulated other comprehensive loss	(1,757)		85		(1,672)
Accumulated deficit	(434,496)		2,946		(431,550)
Total stockholders’ equity	346,927		3,031		349,958
Total liabilities and stockholders’ equity	$	425,011	$	3,556	$	428,567

13

QUANTERIX CORPORATION

RESTATED CONSOLIDATED STATEMENTS OF OPERATIONS

(amounts in thousands, except per share data)

	Three Months Ended March 31, 2024						Three Months Ended March 31, 2023
	As Previously Reported		Adjustments		As Restated		As Previously Reported		Adjustments		As Restated
Revenues:
Product revenue	$	19,670	$	—	$	19,670	$	19,287	$	73	$	19,360
Service revenue	11,967		—		11,967		8,579		(73)		8,506
Collaboration and license revenue	155		—		155		368		—		368
Grant revenue	274		—		274		222		—		222
Total revenues	32,066		—		32,066		28,456		—		28,456
Costs of goods sold and services:
Cost of product revenue	7,145		1,092		8,237		7,033		846		7,879
Cost of service and other revenue	5,295		(14)		5,281		4,497		87		4,584
Total costs of goods sold and services	12,440		1,078		13,518		11,530		933		12,463
Gross profit	19,626		(1,078)		18,548		16,926		(933)		15,993
Operating expenses:
Research and development	6,675		67		6,742		4,720		267		4,987
Selling, general, and administrative	25,993		46		26,039		20,850		(66)		20,784
Other lease costs	924		—		924		776		24		800
Total operating expenses	33,592		113		33,705		26,346		225		26,571
Loss from operations	(13,966)		(1,191)		(15,157)		(9,420)		(1,158)		(10,578)
Interest income	3,948		—		3,948		3,449		—		3,449
Other income (expense), net	206		20		226		8		(13)		(5)
Loss before income taxes	(9,812)		(1,171)		(10,983)		(5,963)		(1,171)		(7,134)
Income tax expense	(260)		80		(180)		(140)		—		(140)
Net loss	$	(10,072)	$	(1,091)	$	(11,163)	$	(6,103)	$	(1,171)	$	(7,274)
Net loss per common share, basic and diluted	$	(0.26)	$	(0.03)	$	(0.29)	$	(0.16)	$	(0.03)	$	(0.19)
Weighted-average common shares outstanding, basic and diluted	38,126		—		38,126		37,327		—		37,327

14

QUANTERIX CORPORATION

RESTATED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

(amounts in thousands)

	Three Months Ended March 31, 2024						Three Months Ended March 31, 2023
	As Previously Reported		Adjustments		As Restated		As Previously Reported		Adjustments		As Restated
Net loss	$	(10,072)	$	(1,091)	$	(11,163)	$	(6,103)	$	(1,171)	$	(7,274)
Other comprehensive income (loss), net of tax:
Unrealized losses on marketable securities	(607)		—		(607)		—		—		—
Foreign currency translation adjustment	(674)		—		(674)		42		—		42
Total other comprehensive income (loss)	(1,281)		—		(1,281)		42		—		42
Comprehensive loss	$	(11,353)	$	(1,091)	$	(12,444)	$	(6,061)	$	(1,171)	$	(7,232)

15

QUANTERIX CORPORATION

RESTATED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(amounts in thousands)

	Three Months Ended March 31, 2024
	Common Stock
As Previously Reported	Shares	Amount		Additional paid-in capital		Accumulated other comprehensive income (loss)		Accumulated deficit		Total stockholders' equity
Balance at December 31, 2023	38,014	$	38	$	783,142	$	(1,757)	$	(434,496)	$	346,927
Issuance of common stock under stock plans, including tax effects	274	—		599		—		—		599
Stock-based compensation expense	—	—		5,265		—		—		5,265
Unrealized loss on marketable securities, net of tax	—	—		—		(607)		—		(607)
Foreign currency translation adjustment	—	—		—		(674)		—		(674)
Net loss	—	—		—		—		(10,072)		(10,072)
Balance at March 31, 2024	38,288	$	38	$	789,006	$	(3,038)	$	(444,568)	$	341,438
Adjustments
Balance at December 31, 2023	—	$	—	$	—	$	85	$	2,946	$	3,031
Issuance of common stock under stock plans, including tax effects	—	—		—		—		—		—
Stock-based compensation expense	—	—		—		—		—		—
Unrealized loss on marketable securities, net of tax	—	—		—		—		—		—
Foreign currency translation adjustment	—	—		—		—		—		—
Net loss	—	—		—		—		(1,091)		(1,091)
Balance at March 31, 2024	—	$	—	$	—	$	85	$	1,855	$	1,940
As Restated
Balance at December 31, 2023	38,014	$	38	$	783,142	$	(1,672)	$	(431,550)	$	349,958
Issuance of common stock under stock plans, including tax effects	274	—		599		—		—		599
Stock-based compensation expense	—	—		5,265		—		—		5,265
Unrealized loss on marketable securities, net of tax	—	—		—		(607)		—		(607)
Foreign currency translation adjustment	—	—		—		(674)		—		(674)
Net loss	—	—		—		—		(11,163)		(11,163)
Balance at March 31, 2024	38,288	$	38	$	789,006	$	(2,953)	$	(442,713)	$	343,378

16

	Three Months Ended March 31, 2023
	Common Stock
As Previously Reported	Shares	Amount		Additional paid-in capital		Accumulated other comprehensive income (loss)		Accumulated deficit		Total stockholders' equity
Balance at December 31, 2022	37,280	$	37	$	763,688	$	(2,623)	$	(402,162)	$	358,940
Issuance of common stock under stock plans, including tax effects	144	—		551		—		—		551
Stock-based compensation expense	—	—		3,902		—		—		3,902
Foreign currency translation adjustment	—	—		—		42		—		42
Net loss	—	—		—		—		(6,103)		(6,103)
Balance at March 31, 2023	37,424	$	37	$	768,141	$	(2,581)	$	(408,265)	$	357,332
Adjustments
Balance at December 31, 2022	—	$	—	$	(59)	$	85	$	(1,034)	$	(1,008)
Issuance of common stock under stock plans, including tax effects	—	—		—		—		—		—
Stock-based compensation expense	—	—		41		—		—		41
Foreign currency translation adjustment	—	—		—		—		—		—
Net loss	—	—		—		—		(1,171)		(1,171)
Balance at March 31, 2023	—	$	—	$	(18)	$	85	$	(2,205)	$	(2,138)
As Restated
Balance at December 31, 2022	37,280	$	37	$	763,629	$	(2,538)	$	(403,196)	$	357,932
Issuance of common stock under stock plans, including tax effects	144	—		551		—		—		551
Stock-based compensation expense	—	—		3,943		—		—		3,943
Foreign currency translation adjustment	—	—		—		42		—		42
Net loss	—	—		—		—		(7,274)		(7,274)
Balance at March 31, 2023	37,424	$	37	$	768,123	$	(2,496)	$	(410,470)	$	355,194

17

QUANTERIX CORPORATION

RESTATED CONSOLIDATED STATEMENTS OF CASH FLOWS

(amounts in thousands)

	Three Months Ended, March 31, 2024
	As Previously Reported		Adjustments		As Restated
Cash flows from operating activities:
Net loss	$	(10,072)	$	(1,091)	$	(11,163)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,523		—		1,523
Credit losses on accounts receivable	176		—		176
Accretion of marketable securities	(1,657)		—		(1,657)
Operating lease right-of-use asset amortization	478		—		478
Stock-based compensation expense	5,265		—		5,265
Other operating activity	55		—		55
Changes in assets and liabilities:
Accounts receivable	(4,233)		—		(4,233)
Inventory	(3,670)		1,139		(2,531)
Prepaid expenses and other current assets	(254)		(27)		(281)
Other non-current assets	(21)		(12)		(33)
Accounts payable	(1,122)		65		(1,057)
Accrued compensation and benefits, accrued expenses, and other current liabilities	(6,126)		(74)		(6,200)
Deferred revenue	472		—		472
Operating lease liabilities	(988)		—		(988)
Other non-current liabilities	10		—		10
Net cash used in operating activities	(20,164)		—		(20,164)
Cash flows from investing activities:
Purchases of marketable securities	(137,889)		—		(137,889)
Proceeds from maturities of marketable securities	29,200		—		29,200
Purchases of property and equipment	(506)		—		(506)
Net cash used in investing activities	(109,195)		—		(109,195)
Cash flows from financing activities:
Proceeds from common stock issued under stock plans	2,037		—		2,037
Payments for employee taxes withheld on stock-based compensation awards	(1,438)		—		(1,438)
Net cash provided by financing activities	599		—		599
Net decrease in cash, cash equivalents, and restricted cash	(128,760)		—		(128,760)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(380)		—		(380)
Cash, cash equivalents, and restricted cash at beginning of period	177,026		—		177,026
Cash, cash equivalents, and restricted cash at end of period	$	47,886	$	—	$	47,886
Supplemental disclosure of cash flow information:
Cash paid for taxes	$	175	$	—	$	175
Purchases of property and equipment in accounts payable and accruals	$	222	$	—	$	222

18

	Three Months Ended, March 31, 2023
	As Previously Reported		Adjustments		As Restated
Cash flows from operating activities:
Net loss	$	(6,103)	$	(1,171)	$	(7,274)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,439		15		1,454
Credit losses on accounts receivable	178		—		178
Operating lease right-of-use asset amortization	334		—		334
Stock-based compensation expense	3,902		41		3,943
Other operating activity	270		—		270
Changes in assets and liabilities:
Accounts receivable	(3,741)		—		(3,741)
Inventory	(89)		619		530
Prepaid expenses and other current assets	(422)		—		(422)
Other non-current assets	(33)		—		(33)
Accounts payable	(1,271)		—		(1,271)
Accrued compensation and benefits, accrued expenses, and other current liabilities	(5,983)		174		(5,809)
Deferred revenue	2,041		—		2,041
Operating lease liabilities	179		—		179
Other non-current liabilities	(203)		—		(203)
Net cash used in operating activities	(9,502)		(322)		(9,824)
Cash flows from investing activities:
Purchases of property and equipment	(136)		—		(136)
Net cash used in investing activities	(136)		—		(136)
Cash flows from financing activities:
Proceeds from common stock issued under stock plans	564		—		564
Payments for employee taxes withheld on stock-based compensation awards	(13)		—		(13)
Net cash provided by financing activities	551		—		551
Net decrease in cash, cash equivalents, and restricted cash	(9,087)		(322)		(9,409)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	24		—		24
Cash, cash equivalents, and restricted cash at beginning of period	341,337		—		341,337
Cash, cash equivalents, and restricted cash at end of period	$	332,274	$	(322)	$	331,952
Supplemental disclosure of cash flow information:
Cash paid for taxes	$	246	$	—	$	246
Purchases of property and equipment in accounts payable and accruals	$	147	$	—	$	147

19

Note 2. Organization and Nature of Business

Quanterix is a life sciences company that has developed next generation, ultra-sensitive digital immunoassay platforms that advance life sciences research and diagnostics. The Company’s platforms are based on its proprietary digital “Simoa” detection technology and enable customers to reliably detect protein biomarkers in ultra-low concentrations in blood, serum, and other fluids that, in many cases, are undetectable using conventional, analog immunoassay technologies. The ability of the Company’s Simoa platforms to detect proteins in the femtomolar range is enabling the development of novel therapies and diagnostics and has the potential to facilitate a paradigm shift in healthcare from an emphasis on treatment to a focus on earlier detection, monitoring, prognosis, and, ultimately, prevention.

The Company also provides contract research services for customers and Laboratory Developed Test (“LDT”) services through its CLIA-certified Accelerator Laboratory (the “Accelerator Laboratory”). The Accelerator Laboratory provides customers with access to its Simoa technology and its Lucent Diagnostics clinical testing services (launched in July 2023) and supports multiple projects and services, including sample testing, homebrew assay development, custom assay development, and blood-based biomarker testing. To date, the Company has completed over 2,300 projects for more than 480 customers from all over the world using its Simoa platforms.

Note 3. Significant Accounting Policies

Basis of Presentation

The accompanying Consolidated Financial Statements and Notes to Consolidated Financial Statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) and pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) regarding interim financial reporting on Form 10-Q. Accordingly, certain information and disclosures required for complete financial statements prepared in accordance with U.S. GAAP are not included herein. The Consolidated Balance Sheet and related information as of December 31, 2023 included herein was derived from the restated audited Consolidated Financial Statements as of December 31, 2023 (as restated), but does not include all disclosures required by U.S. GAAP on an annual reporting basis. Certain amounts in the prior years’ Consolidated Financial Statements have been reclassified to conform to the current year’s presentation.

These Consolidated Financial Statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, originally filed with the SEC on February 29, 2024 (the “Original Annual Report”), and Amendment No. 1 to the Company’s Annual Report on Form 10-K/A for the year ended December 31, 2023, filed with the SEC on December 23, 2024. Since the date of the Original Annual Report, there have been no changes or updates to the Company’s significant accounting policies, other than those described below.

In the opinion of management, the Consolidated Financial Statements and Notes to Consolidated Financial Statements contain all normal, recurring adjustments necessary for a fair statement of financial position, results of operations, comprehensive loss, and cash flows as of the dates and for the interim periods presented. The results of operations for the three months ended March 31, 2024 may not be indicative of the results for the full year ended December 31, 2024, or any other period.

The Company’s fiscal year is the twelve-month period from January 1 through December 31, and all references to “2024,” “2023,” and the like refer to the fiscal year unless otherwise noted.

Use of Estimates

The preparation of the Consolidated Financial Statements and Notes to Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the end of each fiscal period, and the reported amounts of revenues and expenses during each fiscal period. Such estimates include, but are not limited to, revenue recognition, valuation of inventory, leases, valuation and impairment of intangible and long-lived assets, recoverability of deferred tax assets, and stock-based compensation expense. The Company bases its estimates on historical experience, known trends, worldwide economic conditions, both general and specific to the life sciences industry, and other relevant factors it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates and changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.

20

Principles of Consolidation

The Consolidated Financial Statements and Notes to Consolidated Financial Statements include the accounts of Quanterix and its wholly-owned subsidiaries. All intercompany transactions have been eliminated in consolidation.

In accordance with Accounting Standards Codification (“ASC”) 810 – Consolidation, the Company assesses the terms of non-marketable equity investments in entities to determine if any meet the definition of a variable interest entity (“VIE”) and require consolidation into its Consolidated Financial Statements. Refer to Note 15 − Variable Interest Entities for further discussion.

Foreign Currency

The functional currency of the Company’s subsidiaries is their respective local currencies. These subsidiary financial statements are translated into U.S. dollars using the period-end exchange rates for assets and liabilities, average exchange rates during the corresponding period for revenue and expenses, and historical rates for equity. The effects of foreign currency translation adjustments are recorded in accumulated other comprehensive income (loss), a component of stockholders’ equity on the Consolidated Balance Sheets.

Foreign currency transaction gains (losses) are included in other income, net on the Consolidated Statements of Operations and were not material for the three months ended March 31, 2024 and 2023.

Restricted Cash

The following table summarizes the period ending cash and cash equivalents as presented on the Consolidated Balance Sheets and the total cash, cash equivalents, and restricted cash as presented on the Consolidated Statements of Cash Flows (in thousands):

	As of March 31,
	2024		2023
			(As Restated)
Cash and cash equivalents	$	45,281	$	329,354
Restricted cash	2,605		2,598
Cash, cash equivalents, and restricted cash	$	47,886	$	331,952

Restricted cash consists of collateral for a letter of credit issued as security for two of the Company’s leased facilities and to secure the Company’s corporate credit card program. The short-term or long-term classification is determined in accordance with the expiration of the underlying letter of credit and security.

Recently Adopted Accounting Pronouncements

In June 2022, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions (“ASU 2022-03”). This update clarifies the guidance in Topic 820 related to measuring the fair value of an equity security subject to contractual restrictions that prohibit the sale of an equity security, as well as introduces new disclosure requirements for these types of equity securities. The new standard became effective for the Company on January 1, 2024. The Company adopted this standard on a prospective basis and such adoption did not have a material impact on the Company’s Consolidated Financial Statements or related disclosures.

Recent Accounting Standards to be Adopted

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The new standard enhances the disclosures of reportable segment information, primarily with regards to significant segment expenses, and applies to entities with a single reportable segment. The new standard is effective for the Company for annual periods beginning January 1, 2024, and for interim periods beginning January 1, 2025, with early adoption permitted. Upon adoption, the guidance should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of adoption of the standard on its Consolidated Financial Statements disclosures.

21

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The new standard enhances income tax disclosure requirements by requiring specified categories and greater disaggregation within the tax rate reconciliation table, disclosure of income taxes paid by jurisdiction, and providing clarification on uncertain tax positions and related financial statement impacts. The new standard is effective for the Company for annual periods beginning January 1, 2025, with early adoption permitted. The Company is currently evaluating the impact of adoption of the standard on its Consolidated Financial Statements disclosures.

Note 4. Revenue and Related Matters

Revenue from Contracts with Customers

The Company’s customers primarily consist of entities engaged in life sciences research that pursue the discovery and development of new drugs for a variety of neurologic, oncologic, cardiovascular, infectious disease, and other protein biomarkers associated with diseases. The Company’s customer base includes pharmaceutical, biotechnology, contract research organizations, academic, and government institutions.

Disaggregated Revenue

When disaggregating revenue, the Company considers all of the economic factors that may affect its revenues. The following table disaggregates the Company’s revenue from contracts with customers by geography, based on the location products and services are consumed, and revenue type (in thousands):

	Three Months Ended March 31, 2024								Three Months Ended March 31, 2023
	North America		EMEA		Asia Pacific		Total		North America		EMEA		Asia Pacific		Total
	(As Restated)		(As Restated)		(As Restated)				(As Restated)		(As Restated)		(As Restated)		(As Restated)
Product revenue:
Instruments	$	408	$	1,269	$	869	$	2,546	$	2,144	$	1,981	$	1,135	$	5,260
Consumable and other products	10,297		4,299		2,528		17,124		7,497		4,971		1,632		14,100
Total	$	10,705	$	5,568	$	3,397	$	19,670	$	9,641	$	6,952	$	2,767	$	19,360
Service revenue:
Service-type warranties	$	1,637	$	852	$	194	$	2,683	$	1,517	$	675	$	133	$	2,325
Research services	5,762		2,802		127		8,691		5,190		234		115		5,539
Other services	318		248		27		593		381		257		4		642
Total	$	7,717	$	3,902	$	348	$	11,967	$	7,088	$	1,166	$	252	$	8,506
Collaboration and license revenue:
Total	$	155	$	—	$	—	$	155	$	368	$	—	$	—	$	368

For the three months ended March 31, 2024, no customer accounted for more than 10% of the Company’s total revenues and for the three months ended March 31, 2023, one customer accounted for more than 10% of the Company’s total revenues. At March 31, 2024 and December 31, 2023, one customer accounted for more than 10% of the Company’s gross accounts receivable.

22

Eli Lilly and Company Service Revenue Agreements

On February 25, 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. Under the statement of work, the Company receives $1.5 million per calendar quarter, which began in the first quarter of 2022. The statement of work automatically renews on a quarterly basis until Lilly provides a termination notice in accordance with the terms of the Lilly Collaboration Agreement. As of March 31, 2024, the Lilly Collaboration Agreement and the statement of work were still in effect.

Concurrent with the execution of the Lilly Collaboration Agreement, the Company entered into a Technology License Agreement (the “Lilly License”) under which Lilly granted the Company a non-exclusive license to Lilly’s proprietary p-Tau 217 antibody technology for use in research use only products and services and future in vitro diagnostics (“IVD”) applications within the field of Alzheimer’s disease. In consideration of the Lilly 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 royalties on net sales of licensed products.

The Company recognized $1.5 million of revenue from the Lilly Collaboration Agreement during the three months ended March 31, 2024 and 2023.

Contract Assets

There were no contract assets as of March 31, 2024 or December 31, 2023.

Deferred Revenue

During the three months ended March 31, 2024 and 2023, the Company recognized $2.7 million and $2.4 million of revenue, respectively, related to its deferred revenue balance at January 1 of each such period.

Remaining Performance Obligations

As of March 31, 2024, the aggregate amount of transaction prices allocated to performance obligations that were not yet satisfied, or were partially satisfied, was $11.2 million. Of this amount, $10.2 million is expected to be recognized as revenue in the next 12 months, with the remainder expected to be recognized thereafter. The $11.2 million primarily consists of amounts billed for undelivered services related to initial and extended service-type warranties and research services.

Costs to Obtain a Contract

Changes in costs to obtain a contract were as follows (in thousands):

	2024		2023
Balance at December 31 of prior year	$	288	$	377
Capitalization of costs to obtain a contract	97		197
Recognition of costs to obtain a contract	(95)		(191)
Balance at March 31	$	290	$	383

The Company evaluates potential impairment of these amounts at each balance sheet date, and no related impairments were recorded during the three months ended March 31, 2024 and 2023.

Grant Revenue

All of the Company's grant revenue is generated within North America.

23

NIH Grant

On September 21, 2022, the Company and the National Institutes of Health (the “NIH”), an agency of the U.S. Department of Health and Human Services, entered into a contract (the “NIH Grant”) with a total award value of $1.7 million. The NIH granted the Company funding in support of the development of certain point-of-care diagnostic technologies through collaborative efforts. Grant funding is to be used solely for activities related to the point-of-care diagnostic device development project and the contract period runs through August 2025. Receipt of the award value occurs throughout the term of the contract period and after the Company submits for reimbursement of activities related to the grant. As of March 31, 2024, the Company had received $0.8 million of the total award value.

During the three months ended March 31, 2024 and 2023, grant revenue recognized and research and development expenses incurred were not material.

ADDF Grant

On March 24, 2022, the Company and the Alzheimer’s Drug Discovery Foundation (the “ADDF”) entered into a contract (the “ADDF Grant”) with a total funding value of $2.3 million. The ADDF is a charitable venture philanthropy entity that granted the Company funding in support of certain activities for the development of an IVD test for early detection of Alzheimer's disease. The ADDF Grant restricts the Company’s use of the granted funds solely for activities related to the Company’s Alzheimer’s diagnostic test development project and the contract period runs through June 2024. Receipt of the contract funding was subject to achievement of pre-defined milestones, and as of December 31, 2023, the Company had received the total funding value of $2.3 million.

During the three months ended March 31, 2024 and 2023 grant revenue recognized and research and development expenses incurred were not material. As of March 31, 2024, the Company had $1.0 million of deferred revenue related to the ADDF Grant.

Note 5. Allowance for Credit Losses

The change in the allowance for expected credit losses on accounts receivable is summarized as follows (in thousands):

	2024		2023
Balance at December 31 of prior year	$	454	$	118
Provision for expected credit losses	176		178
Write-offs and recoveries collected	(103)		(74)
Balance at March 31	$	527	$	222

24

Note 6. Marketable Securities

The amortized cost, gross unrealized gains, gross unrealized losses, and fair value of the Company’s marketable securities by major security type were as follows (in thousands):

	As of March 31, 2024
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Commercial paper	$	42,947	$	—	$	(40)	$	42,907
U.S. Treasuries	73,033		—		(23)		73,010
U.S. Government agency bonds	78,389		10		(149)		78,250
Corporate bonds	79,012		55		(136)		78,931
Total marketable securities	$	273,381	$	65	$	(348)	$	273,098
Marketable securities are recorded in the following Consolidated Balance Sheets captions:
Cash and cash equivalents							$	16,458
Marketable securities							256,640
Total marketable securities							$	273,098

	As of December 31, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Commercial paper	$	53,482	$	23	$	(12)	$	53,493
U.S. Treasuries	4,896		1		—		4,897
U.S. Government agency bonds	28,366		39		(7)		28,398
Corporate bonds	66,726		289		(8)		67,007
Total marketable securities	$	153,470	$	352	$	(27)	$	153,795
Marketable securities are recorded in the following Consolidated Balance Sheets captions:
Cash and cash equivalents							$	6,893
Marketable securities							146,902
Total marketable securities							$	153,795

The following tables show the fair value and gross unrealized losses of the Company’s available-for-sale securities, with unrealized losses that are not deemed to be other-than-temporary aggregated by major security type and length of time that the individual securities have been in a continuous unrealized loss position (in thousands):

	Less Than 12 Months
As of March 31, 2024	Fair Value		Unrealized Losses
Commercial paper	$	38,497	$	(40)
U.S. Treasuries	73,010		(23)
U.S. Government agency bonds	69,825		(149)
Corporate bonds	48,629		(136)
Total	$	229,961	$	(348)

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	Less Than 12 Months
As of December 31, 2023	Fair Value		Unrealized Losses
Commercial paper	$	32,137	$	(12)
U.S. Government agency bonds	15,861		(7)
Corporate bonds	8,367		(8)
Total	$	56,365	$	(27)

The Company did not have any individual securities in a continuous loss position for greater than 12 months, and there were no individual securities that were in a significant unrealized loss position as of March 31, 2024. For marketable securities in an unrealized loss position, the Company does not intend to sell them before recovery of their amortized cost bases, it is not more likely than not that the Company will be required to sell them before recovery of their amortized cost bases, and the unrealized losses are not credit related. Accordingly, the Company has not recorded any impairment losses or a credit loss allowance.

The Company did not sell any marketable securities or record any realized gains or losses for the three months ended March 31, 2024. At March 31, 2024 and December 31, 2023, the Company had $1.2 million and $1.0 million, respectively, of accrued interest receivable on its marketable securities, which was recorded in prepaid expenses and other current assets on the Consolidated Balance Sheets.

The following table summarizes the contractual maturities of the Company’s marketable securities (in thousands):

	As of March 31, 2024				As of December 31, 2023
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	209,554	$	209,378	$	95,188	$	95,232
Due in one to two years	63,827		63,720		58,282		58,563
Total	$	273,381	$	273,098	$	153,470	$	153,795

Note 7. Fair Value of Financial Instruments

Recurring Fair Value Measurements

The following tables present the Company’s fair value hierarchy for its financial assets that are measured at fair value on a recurring basis (in thousands):

As of March 31, 2024	Total		Quoted prices in active markets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Financial assets:
Cash equivalents: (1)
Money market funds	$	19,792	$	19,792	$	—	$	—
U.S. Treasuries	16,458		—		16,458		—
Total cash equivalents	36,250		19,792		16,458		—
Marketable securities:
Commercial paper	42,907		—		42,907		—
U.S. Treasuries	56,552		—		56,552		—
U.S. Government agency bonds	78,250		—		78,250		—
Corporate bonds	78,931		—		78,931		—
Total marketable securities	256,640		—		256,640		—
Total financial assets	$	292,890	$	19,792	$	273,098	$	—

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As of December 31, 2023	Total		Quoted prices in active markets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Financial assets:
Cash equivalents: (1)
Money market funds	$	155,367	$	155,367	$	—	$	—
Commercial paper	1,996		—		1,996		—
U.S. Treasuries	4,897		—		4,897		—
Total cash equivalents	162,260		155,367		6,893		—
Marketable securities:
Commercial paper	51,498		—		51,498		—
U.S. Government agency bonds	28,398		—		28,398		—
Corporate bonds	67,006		—		67,006		—
Total marketable securities	146,902		—		146,902		—
Total financial assets	$	309,162	$	155,367	$	153,795	$	—

(1)Included in cash and cash equivalents on the Consolidated Balance Sheets.

Cash equivalents and marketable securities classified as Level 2 financial assets are initially valued at their purchase price and subsequently valued at the end of each reporting period utilizing third party pricing services or other observable data. The pricing services utilize industry standard valuation methods, including both income and market-based approaches, and observable market inputs to determine the fair value. These observable market inputs include reportable trades, benchmark yields, credit spreads, broker/dealer quotes, bids, offers, current spot rates, and other industry and economic events.

Nonrecurring Fair Value Measurements

The Company has a non-marketable equity investment in an entity that is evaluated under the VIE guidance (refer to Note 15 - Variable Interest Entities for further discussion). Pursuant to ASC 321 – Investments – Equity Securities, the Company uses the measurement alternative for equity investments without readily determinable fair values and recognizes its non-marketable equity investment at cost, less any impairment, and adjusted for any observable price changes in orderly transactions. The Company’s investment is classified as a Level 3 financial asset. Changes in the inputs and assumptions used to determine the fair value would result in a higher or lower fair value measurement.

The Company’s non-marketable equity investment contains certain restrictions related to the sale or transfer of the securities. The restrictions are in place indefinitely and cannot lapse. No adjustment to the fair value was required as a result of adopting ASU 2022-03 on January 1, 2024.

During the three months ended March 31, 2024 and 2023, the Company did not record any fair value adjustments to its non-marketable equity investment and to date, the cumulative fair value adjustments have not been material. As of March 31, 2024 and December 31, 2023, the carrying value of the non-marketable equity investment was $0.8 million, and is recorded in other non-current assets on the Consolidated Balance Sheets.

Other Fair Value Disclosures

During the three months ended March 31, 2024 and 2023, the Company did not transfer financial assets between levels of the fair value hierarchy. Additionally, there have been no changes to the valuation techniques for Level 2 or Level 3 financial assets.

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Note 8. Inventory

Inventory, net of inventory reserves, consisted of the following (in thousands):

	March 31, 2024		December 31, 2023
	(As Restated)		(As Restated)
Raw materials	$	6,082	$	5,114
Work in process	8,391		5,439
Finished goods	14,161		15,570
Total inventory	$	28,634	$	26,123

Note 9. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):

	March 31, 2024		December 31, 2023
	(As Restated)		(As Restated)
Accrued professional services	$	1,947	$	1,596
Accrued royalties	1,631		1,689
Accrued tax liabilities	1,446		822
Other accrued expenses	1,958		1,948
Total accrued expenses and other current liabilities	$	6,982	$	6,055

Note 10. Stock-Based Compensation

Stock Options

Stock option activity for the three months ended March 31, 2024 is presented below (in thousands, except per share and contractual life amounts):

	Number of options	Weighted-average exercise price per share		Weighted-average remaining contractual life (in years)	Aggregate intrinsic value
Outstanding at December 31, 2023	2,774	$	19.62	7.9	$	26,941
Granted	1,179	22.74
Exercised	(104)	12.34
Forfeited/expired	(181)	20.24
Outstanding at March 31, 2024	3,668	$	20.80	8.3	$	17,741
Exercisable at March 31, 2024	1,297	$	22.24	6.6	$	7,615
Vested and expected to vest at March 31, 2024	3,668	$	20.80	8.3	$	17,741

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Restricted Stock Units

Restricted stock unit (“RSU”) activity for the three months ended March 31, 2024 is presented below (in thousands, except per share amounts):

	Number of shares	Weighted-average grant date fair value per share
Unvested at December 31, 2023	1,328	$	17.87
Granted	446	24.40
Vested	(197)	17.57
Forfeited	(96)	20.52
Unvested at March 31, 2024	1,481	$	19.71

Employee Stock Purchase Plan (“ESPP”)

In December 2017, the Company adopted the 2017 Employee Stock Purchase Plan (the “2017 ESPP”). The 2017 ESPP provides for six-month offering periods commencing and ending as follows: March 1 through August 31, and September 1 through February 28. During the three months ended March 31, 2024, employees purchased 36 thousand shares of the Company’s common stock pursuant to the 2017 ESPP.

Stock-Based Compensation Expense

Stock-based compensation expense was recorded in the following categories on the Consolidated Statements of Operations (in thousands):

	Three Months Ended March 31,
	2024		2023
			(As Restated)
Cost of product revenue	$	281	$	197
Cost of service and other revenue	308		350
Research and development	543		379
Selling, general and administrative	4,133		3,017
Total stock-based compensation expense	$	5,265	$	3,943

As of March 31, 2024, there was $56.0 million of total unrecognized stock-based compensation expense related to unvested RSUs and stock options, which is expected to be recognized over the remaining weighted-average vesting period of 3.1 years.

Note 11. Net Loss Per Share

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

	Three Months Ended March 31,
	2024		2023
	(As Restated)		(As Restated)
Numerator:
Net loss	$	(11,163)	$	(7,274)
Denominator:
Weighted average common shares outstanding, basic and diluted	38,126		37,327
Net loss per share, basic and diluted	$	(0.29)	$	(0.19)

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As the Company was in a net loss position for all periods listed in the table below, the following common share equivalents (calculated on a weighted average basis) were excluded from the calculation of diluted net loss per share (in thousands):

	Three Months Ended March 31,
	2024	2023
Stock options	3,520	2,720
Common stock and RSUs	1,497	1,489
Estimated ESPP purchases	19	26
Total dilutive shares	5,036	4,235

Note 12. Income Taxes (As Restated)

The Company’s effective tax rates were (1.6)% and (2.0)% for the three months ended March 31, 2024 and 2023, respectively. The income tax provision and effective tax rate is driven primarily by a valuation allowance in the United States, partially offset by income taxes in foreign jurisdictions.

The Company maintains a valuation allowance on the majority of its deferred tax assets, and it has concluded that it is more likely than not that the deferred assets will not be utilized.

Note 13. Commitments and Contingencies

Purchase Commitments

STRATEC

During 2022, the Company and STRATEC Consumables GmbH (“STRATEC”) entered into an amendment to the supply agreement with STRATEC (as amended, the “STRATEC Supply Agreement”), related to the supply of discs used in Simoa bead-based instruments. As part of the STRATEC Supply Agreement, the Company agreed to purchase a total of 515 thousand discs to be shipped at various points starting in 2022 and continuing through 2024 at an agreed purchase price per disc.

The total purchase commitment under the STRATEC Supply Agreement is $3.7 million, of which $2.1 million has been paid, and $1.6 million is due within one year from March 31, 2024.

During the three months ended March 31, 2024 and 2023, STRATEC shipped 35 thousand and 75 thousand discs, respectively, to the Company. The Company recorded cost of product revenue related to these shipments of $0.3 million and $0.5 million for the three months ended March 31, 2024 and 2023, respectively. During 2024, STRATEC is required to ship 222 thousand discs to the Company. During the three months ended March 31, 2024, 35 thousand discs were shipped.

Other Purchase Commitments

The Company’s other non-cancellable purchase commitments primarily consist of purchases of raw materials for manufacturing operations under annual and multi-year agreements, some of which have minimum quantity requirements. As of March 31, 2024, the Company’s total purchase commitments under these agreements were $3.8 million, most of which the Company expects to incur in the year ending December 31, 2024.

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License Agreements

Harvard University

In August 2022, the Company and Harvard University (“Harvard”) entered into an exclusive license agreement (the “Harvard License Agreement”) for certain intellectual property owned by Harvard. Pursuant to the Harvard License Agreement, the Company paid an upfront fee of $0.6 million, which was recorded in research and development expenses on the Consolidated Statements of Operations. Under this license, the Company is required to pay Harvard low single-digit royalties on net sales of products and services using the licensed technology, as well as a portion of its applicable sublicense revenues. The Company incurred no royalty expense under the Harvard License Agreement for the three months ended March 31, 2024 and 2023.

Refer to Note 14 − Related Party Transactions for a discussion of a related party relationship with Harvard.

Tufts University

In June 2007, the Company and Tufts University (“Tufts”) entered into a license agreement (the “Tufts License Agreement”) for certain intellectual property owned by Tufts. The Tufts 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 required to pay license and maintenance fees that are creditable against royalties, in addition to low single-digit royalties on direct sales and services, and a royalty on sublicense income. The Company incurred royalty expenses related to the Tufts License Agreement of $0.5 million and $0.4 million during the three months ended March 31, 2024 and 2023, respectively, which was recorded in cost of product revenue on the Consolidated Statements of Operations.

Refer to Note 14 − Related Party Transactions for a discussion of a related party relationship with Tufts.

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 results of operations. The Company records contingent liabilities when losses are probable and estimable. If an estimate of a probable loss is a range and no amount within the range is more likely than any other amount in the range, the Company records the minimum amount of the range.

Leases

The undiscounted future lease payments for non-cancelable operating leases were as follows (in thousands):

Maturity of lease liabilities	As of March 31, 2024
2024 (remainder)	$	5,340
2025	7,254
2026	7,408
2027	7,641
2028	7,880
2029	8,126
Thereafter	7,612
Total lease payments	51,261
Less: imputed interest	10,811
Total operating lease liabilities	$	40,450

The Company’s lease agreement for office and laboratory facilities in Bedford, Massachusetts included a tenant improvement allowance with the landlord that offset a portion of the Company’s construction costs. During the first quarter of 2023, the Company received the final tenant improvement allowance reimbursement of $0.9 million.

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Note 14. Related Party Transactions

In June 2007, the Company entered into the Tufts License Agreement for certain intellectual property owned by Tufts (refer to Note 13 − Commitments and Contingencies). A member of the Company’s Board of Directors was previously affiliated with Tufts and continues to receive compensation from Tufts on a formulaic basis based on royalties and license payments the Company makes to Tufts. At March 31, 2024 and December 31, 2023, open payable balances to Tufts were not material.

In August 2022, the Company entered into the Harvard License Agreement for certain intellectual property owned by Harvard (refer to Note 13 − Commitments and Contingencies). Harvard is required to pay a portion of the payments received from the Company under the Harvard License Agreement to a member of the Company’s Board of Directors. A member of the Company’s Board of Directors is also affiliated with Harvard and Mass General Brigham. Revenue recorded from sales of products and services to Harvard and its affiliates and to Mass General Brigham and its affiliates was $0.3 million for both the three months ended March 31, 2024 and 2023. Cost of product revenue and operating expenses with Harvard and Mass General Brigham were not material for the three months ended March 31, 2024 and 2023. At March 31, 2024 and December 31, 2023, open payables to and receivable balances from Harvard and Mass General Brigham were not material.

In May 2022, the Company and UltraDx Limited (“UltraDx”), a company formed by ARCH Venture Partners (“ARCH”), entered into an agreement (the “UltraDx Agreement”). Under the UltraDx Agreement, the Company agreed to supply UltraDx with HD-X instruments (both fully assembled and disassembled), assays and assay components, and granted a co-exclusive license to manufacture, seek Chinese regulatory approval of (including performance of any necessary research and development activities), and commercialize, HD-X instruments assembled in China and related assays in the Chinese IVD market. At contract inception, the Company determined that UltraDx was a related party because a member of the Company’s Board of Directors was affiliated with ARCH and UltraDx. As of June 7, 2023, this individual was no longer a member of the Company’s Board of Directors. Revenue recorded from sales of products and services to UltraDx totaled $1.1 million for the three months ended March 31, 2024. Cost of product revenue and services was not material for the three months ended March 31, 2024. At March 31, 2024 there was $1.2 million in open receivable balances and no open payable balances to UltraDx.

Revenue and cost of product revenue and services for three months ended March 31, 2023 were not material. At December 31, 2023, there were no open payable balances to UltraDx and open receivable balances from UltraDx were not material.

Note 15. Variable Interest Entities (As Restated)

The Company enters into relationships with, or has investments in, other entities that may be VIEs. The Company assesses the criteria in ASC 810 – Consolidation to determine if any of these entities meet the definition of a VIE and require consolidation into its financial statements. The Company’s analysis determines whether it has a controlling financial interest and also identifies the primary beneficiary of a VIE as the enterprise that has both (1) the power to direct activities of a VIE that most significantly impact the entity’s economic performance and (2) the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to that entity.

Based on the Company’s assessments, it does not have any controlling financial interests in any VIE, and therefore did not consolidate any VIE into its Consolidated Financial Statements during the three months ended March 31, 2024 and 2023.

As of March 31, 2024 and December 31, 2023, the carrying value of the Company’s investment in a VIE was $0.8 million, which was recorded in other non-current assets on the Consolidated Balance Sheets. Refer to Note 7 − Fair Value of Financial Instruments for the Company’s related valuation disclosures. Maximum exposure to losses related to the VIE is limited to its carrying value and the Company does not have any future funding commitments to the VIE.

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our unaudited Consolidated Financial Statements and Notes to Consolidated Financial Statements in the section titled “Part I. Item 1. Financial Statements (Unaudited)” in this Quarterly Report on Form 10-Q/A (the “Amended Report") and our audited Consolidated Financial Statements and Management’s Discussion and Analysis of Financial Condition and Results of Operations included in Amendment No. 1 to our Annual Report on Form 10-K/A for the year ended December 31, 2023, as filed with the U.S. Securities and Exchange Commission (the “SEC”) on December 23, 2024 (the “Amended Annual Report”). Certain columns and rows may not add due to the use of rounded numbers. Percentages presented are calculated from the underlying unrounded numbers. In addition to historical information, the following discussion and analysis contains forward-looking statements that involve risks, uncertainties, and assumptions. Our actual results, performance, or experience may differ materially from those discussed below due to various important factors, risks, and uncertainties, including, but not limited to, those set forth in the sections titled “Part II, Item 1A. Risk Factors” and “Note Regarding Forward-Looking Statements” included in this Amended Report, “Part II, Item 1A. Risk Factors” of the Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2024 (the “Original Report”), as filed with the SEC on May 8, 2024, or “Part I, Item 1A. Risk Factors” of the Amended Annual Report, as may be updated by Part II, Item 1A. Risk Factors in our subsequently filed Quarterly Reports on Form 10-Q. Unless the context otherwise requires, the terms “Quanterix,” the “Company,” “we,” “it,” “us, “and “our” in this Amended Report refer to Quanterix Corporation and its consolidated subsidiaries.

Restatement of Previously Issued Financial Statements

This Management's Discussion and Analysis of Financial Condition and Results of Operations reflects the effects of the restatement of our Consolidated Financial Statements as described in Note 1 - Restatement of Financial Statements (the “Restatement”). For further detail regarding the Restatement, refer to the sections titled “Explanatory Note” and “Part I, Item 4. Controls and Procedures.”

Other than to reflect effects of the Restatement, this discussion does not reflect any information or events occurring after May 8, 2024, the filing date of the Original Report, or modify or update those disclosures affected by events that occurred at a later date or facts that subsequently became known to us, except to the extent they are otherwise required to be included and discussed herein.

Overview (As Restated)

We are a life sciences company that has developed next-generation, ultra-sensitive digital immunoassay platforms that advance life sciences research and diagnostics. Our platforms are based on our proprietary digital “Simoa” detection technology and enable customers to reliably detect protein biomarkers at ultra-low concentrations in blood, serum, and other fluids that, in many cases, are undetectable using conventional, analog immunoassay technologies. The ability of our Simoa platforms to detect proteins in the femtomolar range is enabling the development of novel therapies and diagnostics and has the potential to facilitate a paradigm shift in healthcare from an emphasis on treatment to a focus on earlier detection, monitoring, prognosis, and, ultimately, prevention. Our Simoa platforms have achieved significant scientific validation and commercial adoption, and our Simoa technology has been cited in more than 2,900 scientific publications in areas of high unmet medical need and research interest such as neurology, oncology, cardiology, infectious disease, and inflammation.

Our instruments are designed to be used either with assays fully developed by us, including all antibodies and supplies required to run the assays, or with “homebrew” assay kits where we supply some of the components required for testing and the customer supplies the remaining required elements. Accordingly, our installed instruments generate a recurring revenue stream. As the installed base of our Simoa instruments increases, we expect total consumables revenue to increase.

We commercially launched our HD-X instrument in the second half of 2019. The HD-X is an upgraded version of the Simoa HD-1 (our first Simoa instrument, launched in January 2014), collectively “HD Instruments”, that is designed to deliver significant productivity and operational efficiency improvements, as well as greater user flexibility. The HD-X uses our bead-based technology and assays run on the HD-X are fully automated. By March 31, 2024, approximately 83% of the HD Instrument installed base were HD-X instruments.

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Further, we launched our SR-X instrument in 2017 as a compact desktop instrument with a lower price point, more flexible assay preparation, and a wider range of applications. The SR-X utilizes the same Simoa bead-based technology and assay kits as the HD-X.

With our acquisition of Aushon BioSystems, Inc. in 2018, we acquired a CLIA certified laboratory and proprietary sensitive planar array detection technology. The Clinical Laboratory Improvement Amendments of 1988 (“CLIA”) are federal regulatory standards that apply to all clinical laboratory testing performed on humans in the United States (with the exception of research testing that does not report patient specific results). Leveraging our proprietary sophisticated Simoa image analysis and data analysis algorithms, we further refined the planar array technology to develop the SP-X instrument to provide sensitivity similar to that found in our Simoa bead-based platform. We commercially launched the SP-X instrument in 2019.

Our wholly-owned subsidiary UmanDiagnostics AB (“Uman”), a company located in Umeå, Sweden, supplies neurofilament light (“NfL”), antibodies, and enzyme-linked immunoassay (“ELISA”) kits, which are used by researchers and biopharmaceutical and diagnostics companies world-wide in the detection of NfL to advance the development of therapeutics and diagnostics for neurodegenerative conditions.

We also provide contract research services for customers and Laboratory Developed Test (“LDT”) services through our CLIA-certified Accelerator Laboratory (the “Accelerator Laboratory”). The Accelerator Laboratory provides customers with access to our Simoa technology and our Lucent Diagnostics clinical testing services (launched in July 2023), and supports multiple projects and services, including sample testing, homebrew assay development, custom assay development, and blood-based biomarker testing. To date, we have completed over 2,300 projects for more than 480 customers from all over the world using our Simoa platforms.

We have an extensive base of customers including pharmaceutical, biotechnology, contract research organizations, academic and governmental research institutions. We sell our instruments, consumables, and services through a direct field sales force and support organizations in North America and Europe, and through our own sales force and distributors in additional countries, including Australia, Brazil, China, Czech Republic, India, Hong Kong, Israel, Japan, New Zealand, Qatar, Saudi Arabia, Singapore, South Africa, South Korea, Taiwan, and the United Arab Emirates. In addition, we sell NfL antibodies and NfL ELISA kits directly, and through distributors, worldwide.

As of March 31, 2024, we had cash, cash equivalents, and marketable securities of $301.9 million. Since our inception, we have incurred annual net losses, including net losses of $11.2 million and $7.3 million for the three months ended March 31, 2024 and 2023, respectively. As of March 31, 2024, we had an accumulated deficit of $442.7 million and stockholders’ equity of $343.4 million.

We expect to incur significant expenses and operating losses at least through the next 24 months and we expect our expenses to increase substantially as we:

•expand our sales and marketing efforts to further commercialize our products;

•expand our research and development efforts to improve our existing products and develop and launch new products, particularly if any of our products become subject to additional or more burdensome regulation by the U.S. Food and Drug Administration (the “FDA”);

•invest in Lucent Diagnostics, additional LDTs, and other diagnostics initiatives including entry into translational pharma and clinical diagnostic markets;

•seek Premarket Approval (“PMA”), de novo classification, or 510(k) clearance from the FDA for our existing products or new products if or when we decide to market products for use in the prevention, diagnosis, or treatment of a disease or other condition;

•hire additional personnel to support our growth and research and development;

•strategically acquire and integrate companies or technologies that may be complementary to our business;

•enter into collaboration arrangements, or in-license other products and technologies; and

•add operational, financial, and management information systems.

Recent Business Developments

In March 2024, our Lucent AD p-Tau 217 blood test was granted Breakthrough Device designation by the FDA. This designation is granted to products that have the potential to offer more effective diagnosis of life-threatening diseases with an unmet medical need. Proposed indications for this blood test include use of the test results in patients presenting

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with cognitive impairment who are being evaluated for Alzheimer’s disease risk to aid in diagnostic evaluation. The test is not intended as a stand-alone diagnostic test and test results will be interpreted in conjunction with other diagnostic tools to establish a final clinical diagnosis. This test has not been otherwise cleared or approved by the FDA and Breakthrough Device designation does not guarantee that the FDA review and approval process will be shortened or that an application will be approved. We do not expect material revenue from this test, or other Lucent Diagnostics tests, until late 2024 or later, if at all.

During the fourth quarter of 2023, we substantially completed our six-quarter assay redevelopment program. The objective of this operational program was to improve our ability to manufacture and deliver high-quality assays at scale. We have now launched five new Simoa Advantage PLUS assays, which have been developed using improved protocols, by leveraging manufacturing efficiencies and reagent improvements to provide more consistent results and improved lot-to-lot consistency, and through enabling production of larger lot sizes with extended shelf lives. These assays began shipping to customers in the first quarter of 2024. We expect to continue to apply these improved protocols and manufacturing efficiencies to other existing assays as well as assays that we may develop in the future.

Comparison of Results of Operations for Three Months Ended March 31, 2024 and 2023:

The following table sets forth select Consolidated Statements of Operations data, and such data as a percentage of total revenues (in thousands, except percentages):

	Three Months Ended March 31,								Increase (Decrease)
	2024		% of revenue		2023		% of revenue		Amount		%
	(As Restated)				(As Restated)
Revenues:
Product revenue	$	19,670	61	%	$	19,360	68	%	$	310	2	%
Service and other revenue	11,967		37	%	8,506		30	%	3,461		41	%
Collaboration and license revenue	155		—	%	368		1	%	(213)		(58)	%
Grant revenue	274		1	%	222		1	%	52		23	%
Total revenues	32,066		100	%	28,456		100	%	3,610		13	%
Costs of goods sold and services:
Cost of product revenue	8,237		26	%	7,879		28	%	358		5	%
Cost of service and other revenue	5,281		16	%	4,584		16	%	697		15	%
Total costs of goods sold and services	13,518		42	%	12,463		44	%	1,055		8	%
Gross profit	18,548		58	%	15,993		56	%	2,555		16	%
Operating expenses:
Research and development	6,742		21	%	4,987		18	%	1,755		35	%
Selling, general and administrative	26,039		81	%	20,784		73	%	5,255		25	%
Other lease costs	924		3	%	800		3	%	124		16	%
Total operating expenses	33,705		105	%	26,571		93	%	7,134		27	%
Loss from operations	(15,157)		(47)	%	(10,578)		(37)	%	4,579		43	%
Interest income	3,948		12	%	3,449		12	%	499		14	%
Other income (expense), net	226		1	%	(5)		—	%	231		(4,620)	%
Loss before income taxes	(10,983)		(34)	%	(7,134)		(25)	%	3,849		54	%
Income tax expense	(180)		(1)	%	(140)		—	%	40		29	%
Net loss	$	(11,163)	(35)	%	$	(7,274)	(26)	%	$	3,889	53	%

Revenues (As Restated)

Total revenues increased $3.6 million, or 13%, to $32.1 million for the three months ended March 31, 2024, compared to $28.5 million for the three months ended March 31, 2023.

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Product revenue of $19.7 million for the three months ended March 31, 2024 consisted of instrument sales of $2.5 million and sales of consumables and other products of $17.1 million. This represented an increase of $0.3 million, or 2%, compared to product revenue of $19.4 million for the three months ended March 31, 2023. The increase in product revenue was primarily due to a $3.0 million increase in sales of consumables from increases in both customer demand and selling prices. This increase was partially offset by a $2.7 million decrease in instrument sales due to reduced demand in what we believe is a constrained capital funding environment. Based on this, we expect softness in instrument sales to continue for the remainder of 2024.

Service revenue was $12.0 million for the three months ended March 31, 2024, compared to $8.5 million for the three months ended March 31, 2023, an increase of $3.5 million, or 41% . This increase was primarily due to a $3.2 million increase in Accelerator Laboratory revenue driven by higher volumes of sample testing and assay development services. We expect to see continued growth in Accelerator Laboratory services through 2024.

Cost of Goods Sold and Services (As Restated)

Total cost of goods sold and services increased $1.1 million, or 8%, to $13.5 million for the three months ended March 31, 2024, compared to $12.5 million for the three months ended March 31, 2023.

Cost of product revenue increased $0.4 million, or 5%, to $8.2 million for the three months ended March 31, 2024, compared to $7.9 million for the three months ended March 31, 2023. This increase was primarily due to consumables related revenue increases, including compensation and benefit costs from increased headcount, and was partially offset by decreased costs due to lower instrument revenue.

Cost of service and other revenue increased $0.7 million, or 15%, to $5.3 million for the three months ended March 31, 2024, compared to $4.6 million for the three months ended March 31, 2023. This increase was primarily due to the increase in Accelerator Laboratory revenue, including compensation and benefit costs from increased headcount and increased volume of lab supplies used.

Research and Development (As Restated)

Research and development expense increased $1.8 million, or 35%, to $6.7 million for the three months ended March 31, 2024, compared to $5.0 million for the three months ended March 31, 2023. This increase was primarily due to a $1.1 million increase in compensation and benefits costs related to increased headcount, and a $0.5 million increase in professional services and research lab supplies and equipment to enable product development. We expect research and development expense to continue to increase throughout 2024 due to continued investments in product development and new offerings.

Selling, General and Administrative (As Restated)

Selling, general and administrative expense increased $5.3 million, or 25%, to $26.0 million for the three months ended March 31, 2024, compared to $20.8 million for the three months ended March 31, 2023. The primary reason for the increase is additional headcount to expand the size of our sales team. More specifically, the increase was primarily due to (1) a $3.3 million increase in personnel related costs, primarily compensation and benefits related to increased headcount, (2) a $1.1 million increase in stock-based compensation expense due to increased headcount, and (3) a $0.6 million increase in travel related expenses. Included within selling, general, and administrative expense are $2.1 million and $1.8 million of shipping and handling costs for product sales for the three months ended March 31, 2024 and 2023, respectively.

Other Lease Costs (As Restated)

Other lease costs increased $0.1 million , or 16% to $0.9 million for the three months ended March 31, 2024, compared to $0.8 million for the three months ended March 31, 2023. Following our restructuring in 2022, we are not using two leased office and laboratory facilities and are evaluating alternatives, including sub-leasing the facilities. Other lease costs include amortization of the related operating lease right-of-use assets and other leased facility operating expenses from periods after the restructuring and determination that the facilities would not be used.

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Interest Income

Interest income increased $0.5 million, or 14%, to $3.9 million for the three months ended March 31, 2024, as compared to $3.4 million for the three months ended March 31, 2023. This increase was primarily due to higher interest rates earned on cash, cash equivalents, and marketable securities, and the accretion of discounts from the purchase of marketable securities.

Other Income (Expense), Net (As Restated)

Other income (expense), net was $0.2 million for the three months ended March 31, 2024, as compared to less than $0.1 million for the three months ended March 31, 2023.

Income Tax Expense

Income tax expense was $0.2 million for the three months ended March 31, 2024, as compared to $0.1 million for the three months ended March 31, 2023. The decrease was primarily due to estimated foreign income taxes.

Liquidity and Capital Resources

Our principal sources of liquidity are cash, cash equivalents, marketable securities, and funds generated from sales of our products and services. As of March 31, 2024, we had cash and cash equivalents of $45.3 million and $256.6 million of available for sale marketable securities. Historically we have also financed our operations through equity offerings and borrowings from credit facilities.

We believe our cash, cash equivalents, and marketable securities, along with funds generated from sales of our products and services, will be sufficient to meet our anticipated operating cash requirements for at least 12 months from the date of the Original Report.

Our liquidity requirements have consisted, and we expect that they will continue to consist, of sales and marketing expenses, research and development expenses, working capital, and general corporate expenses. Our future capital requirements will depend on many factors, including, but not limited to, our pace of growth, expansion and introduction of new products and services, including Lucent Diagnostics, and advancing access to our diagnostic tests, market acceptance of our products and services, regulatory requirements, regulatory approval of our products or services, and the effects of competition, technological developments, and broader market and economic trends.

We regularly assess potential acquisitions and pursue acquisitions of complementary businesses, services, and technologies. To the extent our existing cash, cash equivalents, and marketable securities are insufficient to fund future activities or requirements to continue operating our business, we may need to raise additional capital. If the conditions for raising capital are favorable, we may seek to finance future cash needs through public or private equity, debt offerings, or other financings.

If needed, we cannot guarantee that we will be able to obtain additional funds on acceptable terms, or at all. If we raise additional funds by issuing equity or equity-linked securities, our stockholders may experience dilution. Future debt financing, if available, may involve covenants restricting our operations or our ability to incur additional debt. Any debt or equity financing that we raise may contain terms that are not favorable to us or our stockholders. If we raise additional funds through collaboration and licensing arrangements with third parties, it may be necessary to relinquish some rights to our technologies or our products, or grant licenses on terms that are not favorable to us. If we do not have or are not able to obtain sufficient funds, if needed, we may have to delay development or commercialization of our products and services. We also may have to reduce marketing, customer support, or other resources devoted to our products, or cease operations.

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Cash Flows

The following table summarizes our cash flows (in thousands):

	Three Months Ended March 31,
	2024		2023
			(As Restated)
Net cash used in operating activities	$	(20,164)	$	(9,824)
Net cash used in investing activities	(109,195)		(136)
Net cash provided by financing activities	599		551
Net decrease in cash, cash equivalents, and restricted cash	$	(128,760)	$	(9,409)

Net Cash Used in Operating Activities (As Restated)

We derive cash flows from operations primarily from the sale of our products and services. Our cash flows from operating activities are also significantly influenced by our use of cash for operating expenses to develop new products and services, invest in process and product improvements, and increase our sales and marketing efforts. We have historically experienced negative cash flows from operating activities as we have developed our technology, expanded our business, and built our infrastructure. We expect negative cash flows from operating activities will continue in the future.

Net cash used in operating activities was $20.2 million and $9.8 million for the three months ended March 31, 2024 and 2023, respectively. The $10.4 million increase in net cash used in operating activities was primarily driven by an overall increase in our net loss, adjusted for non-cash items including stock-based compensation and the accretion of our marketable securities. The increase was further driven by changes in working capital items, primarily (1) an increase in accounts receivable and deferred revenue from sales timing and revenue growth, (2) an increase in inventory as a result of completing the assay development program and manufacturing and stocking new assays, and (3) a decrease in accrued compensation.

Net Cash Used in Investing Activities

Our primary investing activities consist of purchases of marketable securities to increase the interest income we would otherwise earn in cash accounts. Additionally, we use funds towards capital expenditures for the purchase of property and equipment to support our expanding infrastructure and work force. We expect to continue to incur additional capital expenditures related to these efforts in future periods.

Net cash used in investing activities was $109.2 million during the three months ended March 31, 2024, which consisted of the purchase of $137.9 million of marketable securities and $0.5 million of purchases of property and equipment, offset by proceeds from the maturities of marketable securities of $29.2 million.

Net cash used in investing activities was not material during the three months ended March 31, 2023.

Net Cash Provided by Financing Activities

Financing activities provided $0.6 million of cash during both the three months ended March 31, 2024 and 2023, from sales of our common stock under our employee stock purchase plan and from the exercise of options under our equity incentive plan.

Future Cash Obligations

As of March 31, 2024, there have been no material changes to our contractual obligations and commitments from those described in the section titled “Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in our Amended Annual Report.

In addition to the cash commitments disclosed in our Amended Annual Report, we may have other payables and liabilities that may be legally enforceable but are not considered contractual commitments.

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Critical Accounting Policies and Estimates

Our critical accounting policies and significant estimates that involve a higher degree of judgment and complexity are described in the section titled “Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Critical Accounting Policies, Significant Judgments and Estimates” included in our Amended Annual Report.

There have been no material changes to our critical accounting policies and estimates as previously disclosed in that report.

Non-GAAP Financial Measures

To supplement our financial statements presented on a U.S. GAAP basis, we present non-GAAP gross profit, non-GAAP gross margin, non-GAAP total operating expenses, and non-GAAP loss from operations. These non-GAAP measures are calculated by including shipping and handling costs for product sales within cost of product revenue instead of within selling, general and administrative expenses. We use these non-GAAP measures to evaluate our operating performance in a manner that allows for meaningful period-to-period comparison and analysis of trends in our business and our competitors. We believe that presentation of these non-GAAP measures provides useful information to investors in assessing our operating performance within our industry and to allow comparability to the presentation of other companies in our industry where shipping and handling costs are included in cost of goods sold for products. The non-GAAP financial information presented here should be considered in conjunction with, and not as a substitute for, the financial information presented in accordance with U.S. GAAP.

Set forth below is a reconciliation of non-GAAP gross profit, non-GAAP gross margin, non-GAAP total operating expenses, and non-GAAP loss from operations to their most directly comparable GAAP financial measures (in thousands):

	Three Months Ended March 31,
	2024		2023
	(As Restated)		(As Restated)
GAAP gross profit	$	18,548	$	15,993
Shipping and handling costs	(2,142)		(1,829)
Non-GAAP gross profit	$	16,406	$	14,164
GAAP revenue	$	32,066	$	28,456
GAAP gross margin (gross profit as % of revenue)	57.8%		56.2%
Non-GAAP gross margin (non-GAAP gross profit as % of revenue)	51.2%		49.8%
GAAP total operating expenses	$	33,705	$	26,571
Shipping and handling costs	(2,142)		(1,829)
Non-GAAP total operating expenses	$	31,563	$	24,742
GAAP loss from operations	$	(15,157)	$	(10,578)
Non-GAAP loss from operations	$	(15,157)	$	(10,578)

Recent Accounting Pronouncements

Refer to Note 3 − Significant Accounting Policies in the Notes to Consolidated Financial Statements included in this Amended Report for a full description of recent accounting pronouncements, including the expected dates of adoption and effects on our Consolidated Financial Statements and related disclosures.

ITEM 4. CONTROLS AND PROCEDURES

As previously disclosed in the section titled “Part II, Item 9A. Controls and Procedures” in our Amended Annual Report, management concluded that our internal control over financial reporting was not effective at a reasonable assurance level as of December 31, 2023 due to the material weaknesses in the effectiveness of our internal controls associated with

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the valuation of our inventory, inclusive of the subsequently identified control design deficiency related to the capitalization of labor and overhead costs in our inventory balances (the “Inventory Valuation MW”), and the accounting for property and equipment, net (the “Property and Equipment MW”).

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 our annual or interim financial statements will not be prevented or detected on a timely basis.

Based on our updated evaluation of the effectiveness of internal control over financial reporting under the Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission, and in light of the material weaknesses discussed above, our management continued to conclude that our internal control over financing reporting was not effective at the reasonable assurance level as of March 31, 2024.

If not remediated, or if we identify further material weaknesses in our internal control, our failure to establish and maintain effective disclosure controls and procedures and internal control over financial reporting could result in additional material misstatements in our consolidated financial statements or a failure to meet our reporting and financial obligations.

Evaluation of 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. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives, and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Our disclosure controls and procedures are designed to provide a reasonable assurance of achieving their objectives. 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 March 31, 2024. Because our efforts to remediate the material weaknesses in our internal control over financial reporting are still underway and we have not had a sufficient period of time to test the operating effectiveness of our internal control over financial reporting, which we view as an integral part of our disclosure controls and procedures, 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 March 31, 2024.

Nevertheless, based on a number of factors, including the performance of additional procedures by management designed to ensure the reliability of our financial reporting, we believe that the Consolidated Financial Statements and Notes to Consolidated Financial Statements in this Quarterly Report on Form 10-Q fairly present, in all material respects, our financial position, results of operations, and cash flows as of the dates, and for the periods, presented, in conformity with U.S. GAAP.

Remediation Efforts

Management, with oversight from the Audit Committee of our Board of Directors, continues taking steps to remediate the control deficiencies that resulted in the Inventory Valuation MW and Property and Equipment MW described above by implementing changes to our internal control over financial reporting. Our remediation plans, which include addressing the additional deficiency related to the Restatement, include, but are not limited to, the efforts summarized below:

•we have engaged accounting advisory consultants to:

◦implement new software solutions to automate key manual inventory valuation processes and outputs, some of which we began to use in the second quarter of 2024;

◦assess our current enterprise resource planning system and identify opportunities to enhance our use of the system through automating certain controls and processes, for which development of system enhancements were made and continue to be underway; and

◦design new internal controls evaluating the accounting for inventory, including enhancements to inventory valuation review procedures.

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•we have redesigned our analysis of labor and overhead cost capitalization, including related controls;

•we continue to strengthen and document our existing controls and, starting in the first quarter of 2024, have implemented additional compensating controls and will continue to do so throughout the remainder of fiscal year 2024;

•we continue to execute controls that we worked to improve during fiscal year 2023 that did not have a sufficient period of time to demonstrate operating effectiveness as of December 31, 2023;

•we have hired a Head of SOX Transformation to oversee the remediation of our material weaknesses and further drive improvements across our internal controls;

•we continue to evaluate, enhance, and add personnel in the finance organization with a focus on the requisite experience in the areas of accounting, SEC financial reporting, and associated internal controls;

•we have hired additional accounting consultants to provide additional depth and breadth in our period end closes, financial reporting capabilities, and internal controls compliance until we have filled key additions or vacancies on our team with qualified personnel for a sufficient period of overlap to ensure successful transition of responsibilities;

•we continue to enhance the effectiveness of the related controls based on the recommendations provided by the third-party consulting firm we engaged to assess our remediation plan; and

•we continue to provide trainings on a regular basis related to internal control over financial reporting for all control owners.

We have taken significant steps in our remediation plan and continue our efforts to remediate the material weaknesses described above. We believe that the implementation of the above steps will allow us to address the deficient controls within our internal control environment. 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 expect the remediation of the Property and Equipment MW to continue through fiscal year 2024 and based on the Restatement, we expect the remediation of the Inventory Valuation MW, including the additional control design deficiency, will continue into fiscal year 2025. We will not be able to consider any material weakness 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 the changes outlined to remediate the material weaknesses described above, there were no changes in our internal control over financial reporting during the fiscal quarter ended March 31, 2024 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II — OTHER INFORMATION

ITEM 6. EXHIBITS

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.		10-Q	8/8/2023	001-38319
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 Principal Executive Officer and Principal Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.	X
101.INS	XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.	X
101.SCH	XBRL Taxonomy Extension Schema Document.	X
101.CAL	XBRL Taxonomy Extension Calculation Linkbase Document.	X
101.DEF	XBRL Taxonomy Extension Definition.	X
101.LAB	XBRL Taxonomy Extension Label Linkbase Document.	X
101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document.	X
104	Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101).	X

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SIGNATURES

Pursuant to the requirements 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
Dated: December 23, 2024	By:	/s/ Masoud Toloue
		Masoud Toloue
		President and Chief Executive Officer
		(principal executive officer)
Dated: December 23, 2024	By:	/s/ Vandana Sriram
		Vandana Sriram
		Chief Financial Officer
		(principal financial officer and principal accounting officer)

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