UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
SCHEDULE 13G
 
Under the Securities Exchange Act of 1934
(Amendment No. 2)
 
Quanterix Corporation
(Name of Issuer)
 
Common Stock, $0.001 par value per share
(Title of Class of Securities)
 
74766Q101
(CUSIP Number)
 
 
December 31, 2023
(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)
 
*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.
 
The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).
 
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 control number.
 
13G
CUSIP No. 74766Q101
Page 2 of 6
 
                                             
1. Names of Reporting Persons.
Camber Capital Management LP
42-1693587
 
2. Check the Appropriate Box if a Member of a Group
(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 shares
6. Shared Voting Power
0 shares
 
7. Sole Dispositive Power
0 shares
8. Shared Dispositive Power
0 shares
  9. Aggregate Amount Beneficially Owned by Each Reporting Person
Camber Capital Management LP 0 shares
    10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares       ☐
11. Percent of Class Represented by Amount in Row (9)
Camber Capital Management LP – 0%
12. Type of Reporting Person
Camber Capital Management LP – 00 (Limited Partnership)
 
13G
CUSIP No.    74766Q101
Page 3 of 6

1. Names of Reporting Persons.
Stephen DuBois
Not applicable
 
2. Check the Appropriate Box if a Member of a Group
(a) ☐
(b) ☐
    3. SEC Use Only
4. Citizenship or Place of Organization
Stephen DuBois – United States
   Number of Shares
   Beneficially
   Owned by
   Each Reporting
   Person With:
5. Sole Voting Power
0 shares
6. Shared Voting Power
0 shares
7. Sole Dispositive Power
0 shares
8. Shared Dispositive Power
0 shares
9. Aggregate Amount Beneficially Owned by Each Reporting Person
Stephen DuBois – 0 shares
   10. Check if the Aggregate Amount in Row (9) Excludes Certain Shares       ☐
11. Percent of Class Represented by Amount in Row (9)
Stephen DuBois – 0%
12. Type of Reporting Person
Stephen DuBois – IN
 
13G
  CUSIP No.     74766Q101
Page 4 of 6
 
 
 
ITEM 1.
(a) Name of Issuer:
Quanterix Corporation
 
(b) Address of Issuer's Principal Executive Offices:
900 Middlesex Turnpike Billerica, MA 01821
 
ITEM 2.
(a) Name of Person Filing:
Camber Capital Management LP
Stephen DuBois
 
(b) Address of Principal Business Office, or if None, Residence:
Camber Capital Management LP
Stephen DuBois
101 Huntington Avenue
Suite 2101
Boston, MA 02199
 
(c) Citizenship:
Camber Capital Management LP – Delaware
Stephen DuBois – United States
 
(d) Title of Class of Securities:
Common Stock, $0.001 par value per share
 
(e) CUSIP Number:
74766Q101
 
 
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO SS.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  ss.240.13d-1(b)(1)(ii)(E);   
 
(f)
[_]
An employee benefit plan or endowment fund in accordance with ss.240.13d-1(b)(1)(ii)(F);   
 
(g)
[_]
A parent holding company or control person in accordance with ss.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)
[_]
Group, in accordance with ss.240.13d-1(b)(1)(ii)(J).
 
ITEM 4. OWNERSHIP.
 
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.
 
(a) Amount beneficially owned: Camber Capital Management LP – 0 shares
Stephen DuBois – 0 shares
 
(b) Percent of class: Camber Capital Management LP – 0% 
Stephen DuBois – 0%
 
 
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   CUSIP No.    74766Q101
Page 5 of 6
 
(c) Number of shares as to which such person has:
 
(i) Sole power to vote or to direct the vote
Camber Capital Management LP – 0 shares
Stephen DuBois – 0 shares
 
(ii) Shared power to vote or to direct the vote
Camber Capital Management LP – 0 shares
Stephen DuBois – 0 shares
 
(iii) Sole power to dispose or to direct the disposition of
Camber Capital Management LP – 0 shares
Stephen DuBois – 0 shares
 
(iv) Shared power to dispose or to direct the disposition of
Camber Capital Management LP – 0 shares
Stephen DuBois – 0 shares
 
 
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
 
If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [x].
 
 
ITEM 6. OWNERSHIP OF MORE THAN FIVE 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.
 
Not applicable

ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
 
Not applicable
 
ITEM 9. NOTICE OF DISSOLUTION OF GROUP.
 
Not applicable
 
 
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CUSIP No.    74766Q101
Page 6 of 6
 
 
 
ITEM 10. CERTIFICATIONS.
The following certification shall be included if the statement is filed pursuant to S.240.13d-1(c):
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 such purpose or effect.
 
 
 
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.
 
CAMBER CAPITAL MANAGEMENT LP
By: /s/Sean George
Sean George
Chief Financial Officer
 
STEPHEN DUBOIS
By: /s/ Stephen DuBois
Stephen DuBois, individually
 
The original statement shall be signed by each person on whose behalf the statement is filed or his authorized representative. If the statement is signed on behalf of a person by his authorized representative other than an executive officer or general partner of the filing person, evidence of the representative's authority to sign on behalf of such person shall be filed with the statement, provided, however, that a power of attorney for this purpose which is already on file with the Commission may be incorporated by reference. The name and any title of each person who signs the statement shall be typed or printed beneath his signature.
 
 
 
 
EXHIBIT 1
JOINT FILING AGREEMENT
 
This Joint Filing Agreement dated February 14, 2024 is by and between Camber Capital Management LP, a Delaware limited partnership, and Stephen DuBois, an individual (the foregoing are collectively referred to herein as the "Filers"). Each of the Filers may be required to file with the United States Securities and Exchange Commission a statement on Schedule 13G with respect to common stock, $0.001 par value of Quanterix Corporation beneficially owned by them from time to time. Pursuant to and in accordance with Rule 13(d)(1)(k) promulgated under the Securities Exchange Act of 1934, as amended, the Filers hereby agree to file a single statement on Schedule 13D and/or 13G (and any amendments thereto) on behalf of each of such parties, and hereby further agree to file this Joint Filing Agreement as an exhibit to such statement, as required by such rule. This Joint Filing Agreement may be terminated by any of the Filers upon one week's prior written notice or such lesser period of notice as the Filers may mutually agree.
 
Executed and delivered as of the date first above written.
 
CAMBER CAPITAL MANAGEMENT LP
By: /s/ Sean George
Sean George
Chief Financial Officer
 
    STEPHEN DUBOIS
By: /s/ Stephen DuBois