[Form 4] Quanterix Corp Insider Trading Activity

Rhea-AI Filing Summary

Quanterix CorpEverett CunninghamJanuary 19, 2026813,750 performance-based restricted stock units (RSUs)1,070,000 time-based RSUs

The performance-based RSUs vest only if the volume-weighted average price of Quanterix stock meets specified thresholds within a four-year period, as outlined in his January 8, 2026 employment agreement. The time-based RSUs vest in four equal annual installments on January 19, 2027, 2028, 2029, and 20301,883,750 derivative securities$0

01/21/2026 - 04:15 PM

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Cunningham Everett

(Last) (First) (Middle)

C/O QUANTERIX CORPORATION

900 MIDDLESEX TURNPIKE

(Street)

BILLERICA MA 01821

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Quanterix Corp [ QTRX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
01/19/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Performance-Based Restricted Stock Units	(1)	01/19/2026		A		813,750		(1)	01/20/2030	Common Stock	813,750	$0	813,750	D
Time-Based Restricted Stock Units	(2)	01/19/2026		A		1,070,000		(2)	01/20/2030	Common Stock	1,070,000	$0	1,883,750	D

Explanation of Responses:

1. Each performance-based restricted stock unit ("RSU") represents a contingent right to receive one share of the Issuer's common stock. The performance-based RSUs vest upon the volume-weighted average price of the Issuer's common stock meeting certain thresholds within a four-year period, except as provided for under Section 8(y) of the Employment Agreement by and between the Issuer and the Reporting Person dated January 8, 2026.

2. Each time-based RSU represents a contingent right to receive one share of the Issuer's common stock. The time-based RSUs vest as to one-fourth of the total number of shares on each of January 19, 2027, January 19, 2028, January 19, 2029 and January 19, 2030, except as provided for under Section 8(d) or 8(y) of the Employment Agreement by and between the Issuer and the Reporting Person dated January 8, 2026.

Remarks:

	/s/ Daniel Char, Attorney-in-Fact	01/20/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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