Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Barclay Alec
2. Date of Event Requiring Statement (Month/Day/Year)
03/06/2018
3. Issuer Name and Ticker or Trading Symbol
T2 Biosystems, Inc. [TTOO]
(Last)
(First)
(Middle)
101 HARTWELL AVENUE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Operations
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

LEXINGTON, MA 02421
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 890
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option   (1) 04/25/2026 Common Stock 15,000 $ 9.32 D  
Stock Option   (2) 09/12/2026 Common Stock 10,000 $ 6.79 D  
Stock Option   (3) 01/05/2027 Common Stock 15,000 $ 5.19 D  
Restricted Stock Unit   (4)   (4) Common Stock 20,000 $ (5) D  
Stock Option   (6) 03/01/2028 Common Stock 90,000 $ 5.08 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Barclay Alec
101 HARTWELL AVENUE
LEXINGTON, MA 02421
      SVP, Operations  

Signatures

/s/ Michael Gibbs 03/14/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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).
(1) This Stock Option was granted on April 25, 2016 and vesting commenced on the grant date. Options to purchase 25% of the total underlying shares vest on the first anniversary of the vesting commencement date and options to purchase the remaining shares vest in 36 equal monthly installments thereafter.
(2) This Stock Option was granted on September 12, 2016 and vesting commenced on the grant date. Options to purchase the underlying shares vest in 48 equal monthly installments beginning on the grant date.
(3) This Stock Option was granted on January 5, 2017 and vesting commenced on the grant date. Options to purchase the underlying shares vest in 48 equal monthly installments beginning on the grant date.
(4) The restricted stock units vest in two annual installments beginning on September 11, 2017.
(5) Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock.
(6) This Stock Option was granted on March 1, 2018 and vesting commenced on the grant date. Options to purchase the underlying shares vest in 48 equal monthly installments beginning on the grant date.
 
Remarks:
Exhibit List: Exhibit 24 - Power of Attorney

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