UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 11, 2017

QUANTERIX CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (617) 301-9400

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging Growth Company x

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

Item 5.03              Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

Amendment and Restatement of Certificate of Incorporation

On December 11, 2017, Quanterix Corporation (the “Company”) filed an amended and restated certificate of incorporation (the “Restated Certificate”) with the Secretary of State of the State of Delaware in connection with the closing of its initial public offering (the “IPO”) of common stock. The Company’s board of directors and stockholders previously approved the Restated Certificate effective as of and contingent upon the closing of the IPO.

A copy of the Restated Certificate is attached hereto as Exhibit 3.1 and is incorporated herein by reference.

Amendment and Restatement of Bylaws

The Company also adopted amended and restated bylaws (the “Restated Bylaws”) in connection with the closing of the IPO. The Company’s board of directors and stockholders previously approved the Restated Bylaws effective as of and contingent upon the closing of the IPO.

A copy of the Restated Bylaws is attached hereto as Exhibit 3.2 and is incorporated herein by reference.

Item 8.01.             Other Events.

On December 11, 2017, the Company completed its initial public offering of 4,916,480 shares of its common stock at a public offering price of $15.00 per share, before underwriting discounts and commissions. The initial public offering included the sale of 641,280 shares pursuant to the underwriters’ full exercise of the option to purchase additional shares at the initial public offering price. A copy of the press release announcing the closing of the IPO is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01              Financial Statements and Exhibits.

(d) Exhibits

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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.

Date: December 15, 2017

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