SEC FORM 4 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).
1. Name and Address of Reporting Person*
Geist William

(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)
Director 10% Owner
X Officer (give title below) Other (specify below)
Chief Operating Officer
3. Date of Earliest Transaction (Month/Day/Year)
02/08/2021
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
Common Stock 02/08/2021 A 4,906(1) A $0.00 44,951(2) D
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
Stock Option (right to buy) $77.79 02/08/2021 A 11,447 (3) 02/08/2031 Common Stock 11,447 $0.00 11,447 D
Explanation of Responses:
1. Represents shares of stock issuable on vesting of restricted stock units. The restricted stock units vest as to 25% of the shares on February 8, 2022, and the remaining 75% vest in 36 equal monthly installments at the end of each month beginning on February 28, 2022.
2. Includes 44,951 restricted stock units.
3. The option vests as to 25% of the shares on February 8, 2022, and the remaining 75% vests in 36 equal monthly installments at the end of each month beginning on February 28, 2022.
Remarks:
/s/ Brian Keane, as Attorney-in-Fact 02/10/2021
** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
POWER OF ATTORNEY


      Know all by these presents, that the undersigned hereby
constitutes and appoints John Fry and Brian Keane, each of Quanterix
Corporation, and Megan Gates, John Condon, Keunjung Cho, Amanda Mei,
Anne Leland and Brenda Meyette, each of Mintz, Levin, Cohn, Ferris,
Glovsky and Popeo, P.C., signing singly, with full power of
substitution, the undersigned's true and lawful attorney-in-fact to:
(1)	execute for and on behalf of the undersigned, forms
and authentication documents for EDGAR Filing Access;
(2)	do and perform any and all acts for and on behalf of
the undersigned which may be necessary or desirable to
complete and execute any such forms and authentication
documents;
(3) 	execute for and on behalf of the undersigned, in the
undersigned's capacity as an officer, director and/or
10% shareholder of the Company, Forms 3, 4 and 5 in
accordance with Section 16(a) of the Securities
Exchange Act of 1934 and the rules thereunder;
(4)	do and perform any and all acts for and on behalf of
the undersigned which may be necessary or desirable to
complete and execute any such Form 3, 4 or 5 and
timely file such form with the United States
Securities and Exchange Commission and any stock
exchange or similar authority; and
(5)	take any other action of any type whatsoever in
connection with the foregoing which, in the opinion of
such attorney-in-fact, may be of benefit to, in the
best interest of, or legally required by, the
undersigned, it being understood that the documents
executed by such attorney-in-fact, on behalf of the
undersigned pursuant to this Power of Attorney, shall
be in such form and shall contain such terms and
conditions as such attorney-in-fact may approve in
such attorney-in-fact's discretion.
      The undersigned hereby grants to each such attorney-in-fact full
power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be done in the exercise
of any of the rights and powers herein granted, as fully to all
intents and purposes as the undersigned might or could do if
personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or
such attorney-in-fact's substitute or substitutes, shall lawfully do
or cause to be done by virtue of this power of attorney and the
rights and powers herein granted.  The undersigned acknowledges that
the foregoing attorneys-in-fact, in serving in such capacity at the
request of the undersigned, is not assuming, nor is the Company
assuming, any of the undersigned's responsibilities to comply with
Section 16 of the Securities Exchange Act of 1934.
      This Power of Attorney shall remain in full force and effect
until the undersigned is no longer required to file Forms 3, 4 and 5
with respect to the undersigned's holdings of and transactions in
securities issued by the Company, unless earlier revoked by the
undersigned in a signed writing delivered to the foregoing attorneys-
in-fact.
      IN WITNESS WHEREOF, the undersigned has caused this Power of
Attorney to be executed this 7th day of November 2020.
/s/ William Geist
William Geist