Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
GILLIS STEVEN
   2. Issuer Name and Ticker or Trading Symbol
Pulmatrix, Inc. [PULM] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
8755 W HIGGINS, SUITE 1025, 		 3. Date of Earliest Transaction (Month/Day/Year)
04/03/2018
(Street)

CHICAGO, IL 60631		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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 04/03/2018   P   1,150,000 A (1) 3,436,456 I See Footnotes (2) (3)

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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 Underlying Securities
(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 of Derivative Security: 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
Series A Warrant (right to buy) $ 0.65 04/03/2018   P   1,150,000   04/03/2018 10/03/2018 Common Stock 1,150,000 (1) 1,150,000 I See Footnotes (2) (3)
Series B Warrant (right to buy) $ 0.75 04/03/2018   P   1,150,000   04/03/2018 04/03/2023 Common Stock 1,150,000 (1) 1,150,000 I See Footnotes (2) (3)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
GILLIS STEVEN
8755 W HIGGINS, SUITE 1025
CHICAGO, IL 60631		   X      
Arch Venture Fund VII LP
8755 W HIGGINS, SUITE 1025
CHICAGO, IL 60631		       Former 10% owner
ARCH Venture Partners VII, L.P.
8755 W. HIGGINS ROAD SUITE 1025
CHICAGO, IL 60631		       Former 10% owner
ARCH Venture Partners VII, LLC
8755 W. HIGGINS ROAD SUITE 1025
CHICAGO, IL 60631		       Former 10% owner
CRANDELL KEITH
C/O ARCH VENTURE FUND VII
8755 WEST HIGGINS ROAD, SUITE 1025
CHICAGO, IL 60631		       Former 10% owner
BYBEE CLINTON
C/O ARCH VENTURE FUND VII
8755 WEST HIGGINS ROAD, SUITE 1025
CHICAGO, IL 60631		       Former 10% owner
NELSEN ROBERT
C/O ARCH VENTURE FUND VII
8755 WEST HIGGINS ROAD, SUITE 1025
CHICAGO, IL 60631		       Former 10% owner

Signatures

 /s/ Steve Gillis   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of the general partner of ARCH Venture Fund VII, L.P.   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell, Managing Director of the general partner of ARCH Venture Partners VII, L.P.   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell, Managing Director of ARCH Venture Partners VII, LLC   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Keith Crandell   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Clinton Bybee   04/05/2018
**Signature of Reporting Person Date
 /s/ Mark McDonnell, as Attorney-in-Fact for Robert Nelsen   04/05/2018
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) The reported securities were included within 1,150,000 Units purchased by ARCH Venture Fund VII, L.P. ("ARCH VII") for $0.65 per Unit. Each Unit consisted of one share of common stock, one Series A Warrant to purchase one share of common stock at an exercise price of $0.65 per share, and one Series B Warrant to purchase one share of common stock at an exercise price of $0.75 per share.
(2) Securities held of record byARCH VII. The sole general partner of ARCH VII is ARCH Venture Partners VII, L.P. ("ARCH Partners VII"), which may be deemed to have shared voting and investment power over the shares held by ARCH VII. The sole general partner of ARCH Partners VII is ARCH Venture Partners VII, LLC ("ARCH VII LLC"), which may be deemed to have shared voting and investment power over the shares held by ARCH VII. ARCH Partners VII and ARCH VII LLC disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.
(3) The managing directors of ARCH VII LLC are Keith Crandell, Clinton Bybee and Robert Nelsen and they may be deemed to have shared voting and investment power over the shares held by ARCH VII. Dr. Steve Gillis owns an interest in ARCH Partners VII, but does not have dispositive or voting power. Messrs. Crandell, Bybee and Nelsen and Dr. Gillis disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

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