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): December 31, 2019

UNUM THERAPEUTICS INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (617) 945-5576

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:

Securities registered pursuant to Section 12(b) of the Act:

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

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 December 31, 2019, Unum Therapeutics Inc. (the “Company”) received a letter from the Listing Qualifications Department (the “Staff”) of the Nasdaq Stock Market (“Nasdaq”) notifying the Company that, for the last 30 consecutive business days, the Company’s common stock had not maintained a minimum closing bid price of $1.00 per share (the “Minimum Bid Price Requirement”) pursuant to Nasdaq Listing Rule 5450(a)(1). The Nasdaq letter does not result in the immediate delisting of the Company’s common stock from The Nasdaq Global Select Market.

In accordance with Nasdaq Listing Rule 5810(c)(3)(A) (the “Compliance Period Rule”), the Company has been provided an initial period of 180 calendar days, or until June 29, 2020 (the “Compliance Date”), to regain compliance with the Minimum Bid Price Requirement. If, at any time during this 180-day period, the closing bid price for the Company’s common stock closes at $1.00 or more per share for a minimum of 10 consecutive business days, as required under the Compliance Period Rule, the Staff will provide written notification to the Company that it complies with the Minimum Bid Price Requirement and the common stock will continue to be eligible for listing on The Nasdaq Global Select Market.

If the Company does not regain compliance with the Minimum Bid Price Requirement by the Compliance Date, then, under Nasdaq Listing Rule 5810(c)(3)(A)(i), the Company may transfer to The Nasdaq Capital Market, provided that it meets the continued listing requirement for the market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, except for the Minimum Bid Price Requirement, and the Company would need to provide written notice to Nasdaq of its intention to cure the deficiency during the additional compliance period. Following a transfer to The Nasdaq Capital Market, under Nasdaq Listing Rule 5810(c)(3)(A)(ii), the Company may be eligible for an additional 180 calendar day compliance period.

If the Company is not eligible for the additional compliance period or it appears to the Staff that the Company will not be able to cure the deficiency or if the Staff exercises its discretion to not provide such additional compliance period, the Staff will provide written notice to the Company that its common stock will be subject to delisting. At that time, the Company may appeal the Staff’s delisting determination to a Nasdaq Hearing Panel (the “Panel”). The Company expects that its stock would remain listed pending the Panel’s decision. There can be no assurance that, if the Company does appeal the Staff’s delisting determination to the Panel, such appeal would be successful.

The Company intends to monitor the closing bid price of its common stock and may, if appropriate, consider available options to regain compliance with the Minimum Bid Price Requirement. However, there can be no assurance that the Company will be able to regain compliance with the Minimum Bid Price Requirement, transfer to The Nasdaq Capital Market, secure a second period of 180 days to regain compliance, or maintain compliance with any of the other Nasdaq continued listing requirements.

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.