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SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Quanterix Corp (Name of Issuer)

Common Stock, par value $0.001 (Title of Class of Securities)

74766Q101 (CUSIP Number)

09/30/2025 (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No.

74766Q101

1	Names of Reporting Persons Telegraph Hill Partners III, L.P.
2	Check the appropriate box if a member of a Group (see instructions)   (a)   (b)
3	Sec Use Only
4	Citizenship or Place of Organization DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:	5 Sole Voting Power 0.00 6 Shared Voting Power 2,504,648.00 7 Sole Dispositive Power 0.00 8 Shared Dispositive Power 2,504,648.00
9	Aggregate Amount Beneficially Owned by Each Reporting Person 2,504,648.00
10	Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11	Percent of class represented by amount in row (9) 5.4 %
12	Type of Reporting Person (See Instructions) PN

Comment for Type of Reporting Person:  Row 6, 8, 9 and 11: Includes (i) 2,258,408 shares of common stock held by Telegraph Hill Partners III, L.P. and (ii) 246,240 shares of common stock held by THP III Affiliates Fund, LLC. Row 11: Consists of 46,710,797 shares of Common Stock of the Issuer outstanding on November 4, 2025, based on information publicly disclosed by the Issuer.

SCHEDULE 13G

CUSIP No.

74766Q101

1	Names of Reporting Persons THP III Affiliates Fund, LLC
2	Check the appropriate box if a member of a Group (see instructions)   (a)   (b)
3	Sec Use Only
4	Citizenship or Place of Organization DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:	5 Sole Voting Power 0.00 6 Shared Voting Power 2,504,648.00 7 Sole Dispositive Power 0.00 8 Shared Dispositive Power 2,504,648.00
9	Aggregate Amount Beneficially Owned by Each Reporting Person 2,504,648.00
10	Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11	Percent of class represented by amount in row (9) 5.4 %
12	Type of Reporting Person (See Instructions) PN

Comment for Type of Reporting Person:  Row 6, 8, 9 and 11: Includes (i) 2,258,408 shares of common stock held by Telegraph Hill Partners III, L.P. and (ii) 246,240 shares of common stock held by THP III Affiliates Fund, LLC. Row 11: Consists of 46,710,797 shares of Common Stock of the Issuer outstanding on November 4, 2025, based on information publicly disclosed by the Issuer.

SCHEDULE 13G

CUSIP No.

74766Q101

1	Names of Reporting Persons Telegraph Hill Partners III Investment Management, LLC
2	Check the appropriate box if a member of a Group (see instructions)   (a)   (b)
3	Sec Use Only
4	Citizenship or Place of Organization DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:	5 Sole Voting Power 0.00 6 Shared Voting Power 2,504,648.00 7 Sole Dispositive Power 0.00 8 Shared Dispositive Power 2,504,648.00
9	Aggregate Amount Beneficially Owned by Each Reporting Person 2,504,648.00
10	Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11	Percent of class represented by amount in row (9) 5.4 %
12	Type of Reporting Person (See Instructions) PN

Comment for Type of Reporting Person:  Row 6, 8, 9 and 11: Includes (i) 2,258,408 shares of common stock held by Telegraph Hill Partners III, L.P. and (ii) 246,240 shares of common stock held by THP III Affiliates Fund, LLC. Row 11: Consists of 46,710,797 shares of Common Stock of the Issuer outstanding on November 4, 2025, based on information publicly disclosed by the Issuer.

SCHEDULE 13G

CUSIP No.

74766Q101

1	Names of Reporting Persons Telegraph Hill Partners Management Company, LLC
2	Check the appropriate box if a member of a Group (see instructions)   (a)   (b)
3	Sec Use Only
4	Citizenship or Place of Organization DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:	5 Sole Voting Power 0.00 6 Shared Voting Power 2,504,648.00 7 Sole Dispositive Power 0.00 8 Shared Dispositive Power 2,504,648.00
9	Aggregate Amount Beneficially Owned by Each Reporting Person 2,504,648.00
10	Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11	Percent of class represented by amount in row (9) 5.4 %
12	Type of Reporting Person (See Instructions) PN

Comment for Type of Reporting Person:  Row 6, 8, 9 and 11: Includes (i) 2,258,408 shares of common stock held by Telegraph Hill Partners III, L.P. and (ii) 246,240 shares of common stock held by THP III Affiliates Fund, LLC. Row 11: Consists of 46,710,797 shares of Common Stock of the Issuer outstanding on November 4, 2025, based on information publicly disclosed by the Issuer.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Quanterix Corp
(b)	Address of issuer's principal executive offices: 1900 Middlesex Turnpike Billerica, MA, 01821
Item 2.
(a)	Name of person filing: This Statement is filed on behalf of each of the following persons (collectively, the "Reporting Persons"): (i) Telegraph Hill Partners III, L.P. (ii) THP III Affiliates Fund, LLC (iii) Telegraph Hill Partners III Investment Management, LLC (iv) Telegraph Hill Partners Management Company, LLC
(b)	Address or principal business office or, if none, residence: The address of the principal business and principal office of each of the Reporting Persons is 300 Montgomery Street, Suite 1130, San Francisco, California 94104.
(c)	Citizenship: (i) Telegraph Hill Partners III, L.P. is a Delaware limited partnership. (ii) THP III Affiliates Fund, LLC is a Delaware limited liability company. (iii) Telegraph Hill Partners III Investment Management, LLC is a Delaware limited liability company. (iv) Telegraph Hill Partners Management Company, LLC is a Delaware limited liability company.
(d)	Title of class of securities: Common Stock, par value $0.001
(e)	CUSIP No.: 74766Q101
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),        please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: Telegraph Hill Partners III, L.P. 2,258,408 shares of common stock are held of record by Telegraph Hill Partners III, L.P. ("THP III"). Telegraph Hill Partners III Investment Management, LLC ("THP IM") is the general partner of THP III. Telegraph Hill Partners Management Company, LLC ("THPMC") is the manager of THP IM. THP III Affiliates Fund, LLC 246,240 shares of common stock are held of record by THP III Affiliates Fund, LLC ("THP III AFF"). THP IM is the manager of THP III AFF. THPMC is the manager of THP IM.
(b)	Percent of class: The information required by Item 4(b) is set forth in Rows (5)-(9) and (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.  %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: The information required by Item 4(c) is set forth in Rows (5)-(9) and (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
	(ii) Shared power to vote or to direct the vote: The information required by Item 4(c) is set forth in Rows (5)-(9) and (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
	(iii) Sole power to dispose or to direct the disposition of: The information required by Item 4(c) is set forth in Rows (5)-(9) and (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
	(iv) Shared power to dispose or to direct the disposition of: The information required by Item 4(c) is set forth in Rows (5)-(9) and (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE
	After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Telegraph Hill Partners III, L.P.

Signature: /s/ Rob Hart Name/Title: Rob Hart/Partner, Telegraph Hill Partners III Investment Management, LLC, Its: General Partner, Telegraph Hill Partners Mgmt Company LLC, Its: Manager Date: 11/17/2025

THP III Affiliates Fund, LLC

Signature: /s/ Rob Hart Name/Title: Rob Hart/Partner, Telegraph Hill Partners III Investment Management, LLC, Its: Manager, Telegraph Hill Partners Management Company LLC, Its: Manager Date: 11/17/2025

Telegraph Hill Partners III Investment Management, LLC

Signature: /s/ Rob Hart Name/Title: Rob Hart/Partner, Telegraph Hill Partners Management Company LLC, Its: Manager Date: 11/17/2025

Telegraph Hill Partners Management Company, LLC

Signature: /s/ Rob Hart Name/Title: Rob Hart/Partner Date: 11/17/2025

EXHIBIT A

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing on behalf of each of them of a Statement on Schedule 13G (including any and all amendments thereto) with respect to the shares of common stock, $0.001 par value per share, of Quanterix Corporation, and further agree that this Joint Filing Agreement shall be included as an exhibit to such joint filings.

The undersigned further agree that each party hereto is responsible for the timely filing of such Statement on Schedule 13G and any amendments thereto, and for the accuracy and completeness of the information concerning such party contained therein; provided, however, that no party is responsible for the accuracy or completeness of the information concerning any other party, unless such party knows or has reason to believe that such information is inaccurate.

This Joint Filing Agreement may be signed in counterparts with the same effect as if the signature on each counterpart were upon the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of November 17, 2025.

Exhibit B

Due to the relationships between them, the reporting persons hereunder may be deemed to constitute a “group” with one another for purposes of Section 13(d)(3) of the Securities Exchange Act of 1934.