UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED):    May 8, 2018

PULMATRIX, INC.

(Exact name of registrant as specified in its charter)

99 Hayden Avenue, Suite 390

Lexington, MA 02421

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (781) 357-2333

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company     ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

On May 8, 2018, Pulmatrix, Inc. (the “Company”) received a letter from the Listing Qualifications Department of the Nasdaq Stock Market (“Nasdaq”) indicating that, based upon the closing bid price of the Company’s common stock for the last 30 consecutive business days, the Company did not meet the minimum bid price of $1.00 per share required for continued listing on The Nasdaq Global Market pursuant to Nasdaq Listing Rule 5450(a)(1). The letter also indicated that the Company will be provided with a compliance period of 180 calendar days, or until November 5, 2018 (the “Compliance Period”), in which to regain compliance pursuant to Nasdaq Listing Rule 5810(c)(3)(A). The letter further provided that if, at any time during the Compliance Period, the closing bid price of the Company’s common stock is at least $1.00 for a minimum of ten consecutive business days, Nasdaq will provide the Company with written confirmation that it has achieved compliance with the minimum bid price requirement.

If the Company does not regain compliance by the end of the Compliance Period, under Nasdaq Listing Rule 5810(c)(3)(A)(ii), if on the last day of the Compliance Period the Company is in compliance with the market value of publicly held shares requirement for continued listing as well as all other standards for initial listing of its common stock on The Nasdaq Capital Market (other than the bid price requirement), the Company may apply to transfer the listing of its common stock to The Nasdaq Capital Market if the Company also provides written notice to Nasdaq of its intention to cure the deficiency during a second compliance period (by effecting a reverse stock split if necessary), at which point Nasdaq may grant the Company additional time to regain compliance with the minimum bid price requirement.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.