Filing Details

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See §240.13d-7 for other parties to whom copies are to be sent.

*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 disclosures provided in a prior cover page.

The information required on 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).

This Amendment No. 5 (the "Amendment No. 5") to the statement filed on Schedule 13D on June 25, 2015 (the "Original 13D"), as amended by Amendment No. 1 (the "Amendment No. 1") filed on February 7, 2017, Amendment No. 2 (the "Amendment No. 2") filed on January 5, 2018, Amendment No. 3 (the "Amendment No. 3") filed on April 12, 2018, and Amendment No. 4 (the "Amendment No. 4") filed on March 26, 2019, relating to the Common Stock, $0.0001 par value per share (the "Common Stock"), of Pulmatrix, Inc. (the "Issuer") having its principal executive office at 99 Hayden Avenue, Suite 390, Lexington, MA, 02421 (the "Original 13D", together with this Amendment No. 5, Amendment No. 4, Amendment No. 3, Amendment No. 2 and Amendment No. 1, the "Schedule 13D") amends the Original 13D as set forth herein.

Certain terms used but not defined in this Amendment No. 5 shall have the meanings assigned thereto in the Original 13D (as amended by Amendment No. 1, Amendment No. 2, Amendment No. 3 and Amendment No. 4). Except as specifically provided herein, this Amendment No. 5 does not modify any of the information previously reported in the Original 13D, Amendment No. 4, Amendment No. 3, Amendment No. 2 or Amendment No. 1.

(a)

This statement is being filed by: (1) ARCH Venture Fund VII, L.P. ("ARCH Venture Fund VII"), (2) ARCH Venture Partners VII, L.P. ("AVP VII LP"), which is the sole general partner of ARCH Venture Fund VII, (3) ARCH Venture Partners VII, LLC ("AVP VII LLC"), which is the sole general partner of AVP VII LP, (4) Clinton Bybee ("Bybee"), (5) Keith Crandell ("Crandell"), and (6) Robert Nelsen ("Nelsen" and, together with Bybee and Crandell, collectively, the "Managing Directors" and each individually, a "Managing Director").  Each of the individuals and entities above shall be referred to herein individually as a "Reporting Person" and collectively as the "Reporting Persons".

(b)

The business address of each of the Reporting Persons is 8755 West Higgins Road, Suite 1025, Chicago, IL, 60631.

(c)

The principal business of ARCH Venture Fund VII is to invest and assist in developmental and emerging businesses located principally in the United States.  The principal business of AVP VII LP is to act as the general partner of ARCH Venture Fund VII.  The principal business of AVP VII LLC is to act as the general partner of AVP VII LP.  The principal business of each of the Managing Directors is to act as managing directors of AVP VII LLC and a number of affiliated partnerships with similar businesses.

(d)

During the five years prior to the date hereof, none of the Reporting Persons has been convicted in a criminal proceeding.

(e)

During the five years prior to the date hereof, none of the Reporting Persons has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction ending in a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

(f)

Each of ARCH Venture Fund VII and AVP VII LP is a Delaware limited partnership.  AVP VII LLC is a Delaware limited liability company.  Each of the Managing Directors is a United States citizen.