Momentus Inc. has received an updated Schedule 13G/A from a group of Citadel-related entities and Kenneth Griffin regarding holdings of its Class A common stock. The reporting persons may be deemed to beneficially own up to 309,865 Shares, representing 1.6% of the outstanding Class A common stock, based on 18,835,815 Shares outstanding as of June 18, 2026. All reported powers to vote and dispose are on a shared, not sole, basis, and the group reports ownership of 5 percent or less of the class.
"may be deemed to beneficially own 248,366 Shares"
Beneficially own means having the economic rights and risks of a security—such as the right to receive dividends, sell the shares, or profit from price changes—whether or not your name appears on the official share register. Think of it like renting a car: you use it and reap the benefits even if the title lists someone else. Investors care because beneficial ownership determines who truly controls value, must be disclosed under securities rules, and can signal potential influence or trading activity that affects a stock’s price.
shared voting powerfinancial
"Shared Voting Power 248,366.00"
Shared voting power occurs when two or more parties jointly have the right to vote or decide how a block of company shares is cast, like co-owners who must agree before moving a piece of furniture. Investors care because who controls voting rights affects board elections, major corporate decisions and takeover outcomes, and shared control can alter regulatory disclosures and the practical influence any holder has over a company’s direction and value.
shared dispositive powerfinancial
"Shared Dispositive Power 309,865.00"
Schedule 13G/Aregulatory
"Amendment No. 1 to a Schedule 13G/A"
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
attorney-in-factregulatory
"Seth Levy is signing on behalf of Kenneth Griffin as attorney-in-fact"
An attorney-in-fact is the person or entity given legal authority through a power of attorney to act on behalf of another for specific tasks, such as signing documents, voting shares, or handling transactions. For investors, this matters because it lets a trusted representative make timely decisions or complete paperwork when the owner cannot, much like handing keys to someone to run errands on your behalf—so checks on scope and limits of that authority are important.
FAQ
What stake in Momentus Inc. (MNTS) is reported by Kenneth Griffin and related Citadel entities?
Kenneth Griffin may be deemed to beneficially own 309,865 Shares of Momentus Inc., representing 1.6% of the Class A common stock. This is based on 18,835,815 Shares outstanding as of June 18, 2026.
How many Momentus (MNTS) shares are reported by Citadel Advisors and its related investment entities?
Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may each be deemed to beneficially own 248,366 Shares, or 1.3% of Momentus’s Class A common stock, with shared voting and dispositive power over those shares.
What position in Momentus Inc. (MNTS) is reported by Citadel Securities entities?
Citadel Securities LLC may be deemed to beneficially own 61,499 Shares, or 0.3% of Momentus, and each of Citadel Securities Group LP and Citadel Securities GP LLC may also be deemed to beneficially own 61,499 Shares, all with shared voting and dispositive power.
Does the Citadel and Kenneth Griffin group own more than 5% of Momentus (MNTS)?
No. The reporting persons state that their holdings constitute 5 percent or less of Momentus’s Class A common stock. Mr. Griffin’s reported beneficial ownership is 1.6% of the shares outstanding as of June 18, 2026.
What share count did Citadel and Kenneth Griffin use to calculate their Momentus (MNTS) ownership percentages?
The ownership percentages are calculated using 18,835,815 Shares of Momentus Class A common stock outstanding as of June 18, 2026, as referenced from the issuer’s prospectus dated that same day.
Do Citadel and Kenneth Griffin report sole or shared voting power over Momentus (MNTS) shares?
They report zero sole voting or dispositive power. All reported positions reflect shared power to vote and dispose, including 309,865 Shares over which Kenneth Griffin may be deemed to share voting and dispositive authority.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)
Momentus Inc.
(Name of Issuer)
Class A common stock, par value $0.00001 per share (the "Shares")
(Title of Class of Securities)
60879E408
(CUSIP Number)
06/30/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel Advisors LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
248,366.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
248,366.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
248,366.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
1.3 %
12
Type of Reporting Person (See Instructions)
IA, HC, OO
Comment for Type of Reporting Person: The percentages reported in this Schedule 13G are based upon 18,835,815 Shares outstanding as of June 18, 2026 (according to the issuer's prospectus as filed with the Securities and Exchange Commission on June 18, 2026).
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel Advisors Holdings LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
248,366.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
248,366.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
248,366.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
1.3 %
12
Type of Reporting Person (See Instructions)
HC, PN
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel GP LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
248,366.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
248,366.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
248,366.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
1.3 %
12
Type of Reporting Person (See Instructions)
HC, OO
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel Securities LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
61,499.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
61,499.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
61,499.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
BD, OO
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel Securities Group LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
61,499.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
61,499.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
61,499.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
HC, PN
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Citadel Securities GP LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
61,499.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
61,499.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
61,499.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
HC, OO
SCHEDULE 13G
CUSIP Number(s):
60879E408
1
Names of Reporting Persons
Kenneth Griffin
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
309,865.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
309,865.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
309,865.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
1.6 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Momentus Inc.
(b)
Address of issuer's principal executive offices:
1762 Automation Parkway, San Jose, CA 95131
Item 2.
(a)
Name of person filing:
This Schedule 13G is being jointly filed by Citadel Advisors LLC ("Citadel Advisors"), Citadel Advisors Holdings LP ("CAH"), Citadel GP LLC ("CGP"), Citadel Securities LLC ("Citadel Securities"), Citadel Securities Group LP ("CALC4"), Citadel Securities GP LLC ("CSGP") and Mr. Kenneth Griffin (collectively with Citadel Advisors, CAH, CGP, Citadel Securities, CALC4 and CSGP, the "Reporting Persons") with respect to the Shares of the above-named issuer held of record by Citadel Multi-Strategy Equities Master Fund Ltd., a Cayman Islands company ("CM"), Citadel CEMF Investments Ltd., a Cayman Islands limited company ("CCIL"), and Citadel Securities. Such Shares may include other instruments exercisable for or convertible into Shares.
Citadel Advisors is the portfolio manager for CCIL and CM. CAH is the sole member of Citadel Advisors. CGP is the general partner of CAH. CALC4 is the non-member manager of Citadel Securities. CSGP is the general partner of CALC4. Mr. Griffin is the President and Chief Executive Officer of CGP, and owns a controlling interest in CGP and CSGP.
(b)
Address or principal business office or, if none, residence:
The address of each of the Reporting Persons is 830 Brickell Plaza, Miami, Florida 33131.
(c)
Citizenship:
Each of Citadel Advisors, CGP, Citadel Securities and CSGP is organized as a limited liability company under the laws of the State of Delaware. Each of CALC4 and CAH is organized as a limited partnership under the laws of the State of Delaware. Mr. Griffin is a U.S. citizen.
(d)
Title of class of securities:
Class A common stock, par value $0.00001 per share (the "Shares")
(e)
CUSIP No.:
60879E408
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own 248,366 Shares.
2. Citadel Securities LLC may be deemed to beneficially own 61,499 Shares.
3. Each of Citadel Securities Group LP and Citadel Securities GP LLC may be deemed to beneficially own 61,499 Shares.
4. Mr. Griffin may be deemed to beneficially own 309,865 Shares.
(b)
Percent of class:
1. The number of Shares that each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC may be deemed to beneficially own constitutes 1.3% of the Shares outstanding.
2. The number of Shares that Citadel Securities LLC may be deemed to beneficially own constitutes 0.3% of the Shares outstanding.
3. The number of Shares that each of Citadel Securities Group LP and Citadel Securities GP LLC may be deemed to beneficially own constitutes 0.3% of the Shares outstanding.
4. The number of Shares that Mr. Griffin may be deemed to beneficially own constitutes 1.6% of the Shares outstanding.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 0
2. Citadel Securities LLC: 0
3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 0
4. Mr. Griffin: 0
(ii) Shared power to vote or to direct the vote:
1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 248,366
2. Citadel Securities LLC: 61,499
3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 61,499
4. Mr. Griffin: 309,865
(iii) Sole power to dispose or to direct the disposition of:
1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 0
2. Citadel Securities LLC: 0
3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 0
4. Mr. Griffin: 0
(iv) Shared power to dispose or to direct the disposition of:
1. Each of Citadel Advisors LLC, Citadel Advisors Holdings LP and Citadel GP LLC: 248,366
2. Citadel Securities LLC: 61,499
3. Each of Citadel Securities Group LP and Citadel Securities GP LLC: 61,499
4. Mr. Griffin: 309,865
Item 5.
Ownership of 5 Percent or Less of a Class.
Ownership of 5 percent or less of a class
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
Citadel Advisors LLC
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Citadel Advisors Holdings LP
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Citadel GP LLC
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Citadel Securities LLC
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Citadel Securities Group LP
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Citadel Securities GP LLC
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, Authorized Signatory
Date:
08/14/2026
Kenneth Griffin
Signature:
/s/ Seth Levy
Name/Title:
Seth Levy, attorney-in-fact*
Date:
08/14/2026
Comments accompanying signature: * Seth Levy is signing on behalf of Kenneth Griffin as attorney-in-fact pursuant to a power of attorney previously filed with the Securities and Exchange Commission, and hereby incorporated by reference herein. The power of attorney was filed as an attachment to a filing by Citadel Advisors LLC on Schedule 13G for Allakos Inc. on October 13, 2023.
