Form 8-K

8-K — Momentus Inc.

Accession: 0001140361-26-025776

Filed: 2026-06-18

Period: 2026-06-18

CIK: 0001781162

SIC: 3760 (GUIDED MISSILES & SPACE VEHICLES & PARTS)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — ef20076131_8k.htm (Primary)

EX-5.1 — EXHIBIT 5.1 (ef20076131_ex5-1.htm)

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8-K

8-K (Primary)

Filename: ef20076131_8k.htm · Sequence: 1

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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

June 18, 2026

Date of Report (date of earliest event reported)

Momentus Inc.

(Exact name of registrant as specified in its charter)

Delaware

001-39128

84-1905538

(State or other jurisdiction of incorporation or organization)

(Commission File Number)

(I.R.S. Employer Identification No.)

1762 Automation Parkway

San Jose, California

95131

(Address of Principal Executive Offices)

(Zip Code)

(650) 564-7820

Registrant’s telephone number, including area code

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))

Securities registered pursuant to section 12(g) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Class A common stock

MNTS

The Nasdaq Stock Market LLC

Warrants

MNTSW

The Nasdaq Stock Market LLC

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. ☐

Item 8.01

Other Events

Momentus Inc. (the “Company”), is a party to a Sales Agreement (the “Sales Agreement”) with A.G.P./Alliance Global Partners (the “Agent”), pursuant to which the

Company may sell, from time to time, at its option, up to $75 million in aggregate principal amount of an indeterminate amount of shares (the “Shares”) of the Company’s Class A common stock, par value $0.00001 per share, through the Agent, as the

Company’s sales agent (the “ATM Offering”). This aggregate principal amount does not include shares of the Company’s common stock sold pursuant to the Sales Agreement before today’s date.

Any additional Shares to be offered and sold under the Sales Agreement will be issued and sold (i) by methods deemed to be an “at-the-market offering” as defined in

Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or in negotiated transactions, if authorized by the Company, and (ii) pursuant to the Company’s Registration Statement on Form S-3 (File No. 333- 296218) initially filed with

the Securities and Exchange Commission (the “SEC”) on May 26, 2026 (the “Registration Statement”) and declared effective by the SEC on June 4, 2026, and the prospectus supplement relating to the ATM Offering filed with the SEC on June 18, 2026.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy the Shares nor shall there be any sale of the Shares in

any state in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

The opinion of the Company’s legal counsel, Bradley Arant Boult Cummings LLP, regarding the validity of the Shares is filed as Exhibit 5.1 hereto. This opinion is also

filed with reference to, and is hereby incorporated by reference into, the Registration Statement.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits

Exhibit

Number

Exhibit Description

5.1

Opinion of Bradley Arant Boult Cummings LLP

23.1

Consent of Bradley Arant Boult Cummings LLP (included in Exhibit 5.1)

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURE

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.

By:

/s/ Lon Ensler

Name:

Lon Ensler

Title:

Chief Financial Officer

Dated:

June 18, 2026

EX-5.1 — EXHIBIT 5.1

EX-5.1

Filename: ef20076131_ex5-1.htm · Sequence: 2

Exhibit 5.1

June 18, 2026

Momentus Inc.

1762 Automation Parkway

San Jose, CA 95131

Ladies and Gentlemen:

We have acted as counsel to Momentus Inc., a Delaware corporation (the “Company”),

in connection with the offering by the Company of shares of its Class A common stock, par value $0.00001 per share (the “Common Stock”), having an initial aggregate offering price of up to

$75,000,000 (the “Shares”) pursuant to the Registration Statement on Form S-3 (Registration No. 333–296218) (the “Registration Statement”) filed by the Company with the Securities and Exchange Commission (the “SEC”) under

the Securities Act of 1933, as amended (the “Securities Act”), and the prospectus included in the

Registration Statement (the “Base Prospectus”), as supplemented by the prospectus supplement filed with the SEC on June 18, 2026 relating to the offer and sale from time to time by the Company of the Shares (together with the Base

Prospectus, the “Prospectus”). The Shares are to be sold by the Company in accordance with that certain Sales Agreement, dated September 19, 2025, between the Company and A.G.P./Alliance Global Partners (such agreement, the “Sales

Agreement”), as described in the Prospectus.

In connection with this opinion, we have examined the

Registration Statement and the Prospectus, the Sales Agreement, the Second Amended and Restated Certificate of Incorporation, as amended, and the Amended and Restated Bylaws, as amended, of the Company, and originals, or copies certified or

otherwise identified to our satisfaction, of such records, documents, certificates and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. In such examination, we have assumed, and express no opinion as to, the authenticity of original documents and the genuineness of all signatures, the authenticity of all documents submitted

to us as originals, the conformity to the originals of all documents submitted to us as copies, the truth, accuracy and completeness of the information, representations and warranties contained in the instruments, documents, certificates and

records we have reviewed, the legal capacity of all natural persons or entities (except for the Company), the absence of any undisclosed termination, modification, waiver or amendment to any document reviewed by us, the absence of any other

extrinsic agreements or documents that might change or affect the interpretation or terms of documents where due authorization, execution and delivery of all such documents by all persons other than the Company where authorization, execution

and delivery are prerequisites to the effectiveness thereof. In giving our opinion, we have also relied upon a good standing certificate regarding the Company issued by the Delaware Secretary of State dated June 18, 2026, and as to any facts

material to the opinions expressed herein that were not independently established or verified, we have relied upon oral or written statements and representations of officers and other representatives of the Company.

Our opinion herein is expressed solely with respect to the General Corporation Law of the State of Delaware.

On the basis of the foregoing and in reliance thereon, we are of the opinion that the Shares have been duly authorized for issuance and, when

the Shares are issued and paid for in accordance with the terms and conditions of the Sales Agreement, the Shares will be validly issued, fully paid and nonassessable.

Our opinion expressed above is made as of the date hereof and is subject to, and may be limited by, future changes in the factual matters set

forth herein, and we undertake no duty to advise you of the same. The opinion set forth herein is based upon the law in effect (and published or otherwise generally available) on the date hereof, and we assume no obligation to revise or

supplement this opinion should such law be changed by legislative action, judicial decision or otherwise. In rendering our opinion, we have not considered, and hereby disclaim any opinion as to, the application or impact of any laws, cases,

decisions, rules or regulations of any other jurisdiction, court or administrative agency.

We hereby consent to the reference to our firm under the caption “Legal Matters” in the Prospectus and to the filing of this opinion as an

exhibit to the Company’s Current Report on Form 8-K filed with the SEC on or about the date hereof and incorporated by reference into the Registration Statement. In giving such consent, we do not believe that we are “experts” within the meaning

of such term as used in the Securities Act or the rules and regulations of the SEC issued thereunder with respect to any part of the Registration Statement, including this opinion as an exhibit.

Very truly yours,

/s/ Bradley Arant Boult Cummings LLP

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