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): February 24, 2020

TRINE ACQUISITION CORP.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (212) 503-2855

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):

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 (§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  þ

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 February 24, 2020, Trine Acquisition Corp. (the “Company”) issued an unsecured promissory note (the “Note”) in the principal amount of up to $1,500,000 to Trine Sponsor IH, LLC (the “Sponsor”). The Note bears no interest and is repayable in full upon consummation of the Company’s initial business combination. The Sponsor has the option to convert any unpaid balance of the Note into warrants to purchase one share of Class A common stock, $0.0001 par value per share, of the Company (the “Working Capital Warrants”) equal to the principal amount of the Note so converted divided by $1.00. The terms of any such Working Capital Units will be identical to the terms of the warrants issued by the Company to the Sponsor in a private placement of the Company’s initial public offering.

The issuance of the Note was made pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act of 1933, as amended.

The Note is attached as Exhibit 10.1 to this Current Report on Form 8-K and is incorporated herein by reference. The disclosure set forth in this Item 2.03 is intended to be a summary only and is qualified in its entirety by reference to the Note.

(d) Exhibits

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.

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