SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

SEACOR Marine Holdings Inc.

(Name of Issuer)

Common Stock, par value $.01 per share

(Title of Class of Securities)

78413P101

(CUSIP Number)

03/31/2026

(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)

SCHEDULE 13G

CUSIP Number(s):

78413P101

Names of Reporting Persons

P. Oppenheimer Investment Parternship, LP

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 530,010.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 530,010.00
8	Shared Dispositive Power 0.00

Aggregate Amount Beneficially Owned by Each Reporting Person

530,010.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

1.97 %

Type of Reporting Person (See Instructions)

SCHEDULE 13G

CUSIP Number(s):

78413P101

Names of Reporting Persons

Oppenheimer-Close Investment Partnership, LP

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 147,961.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 147,961.00
8	Shared Dispositive Power 0.00

Aggregate Amount Beneficially Owned by Each Reporting Person

147,961.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

0.55 %

Type of Reporting Person (See Instructions)

SCHEDULE 13G

CUSIP Number(s):

78413P101

Names of Reporting Persons

Oppenheimer + Close, LLC

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 102,766.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 102,766.00
8	Shared Dispositive Power 0.00

Aggregate Amount Beneficially Owned by Each Reporting Person

734,647.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

2.73 %

Type of Reporting Person (See Instructions)

SCHEDULE 13G

CUSIP Number(s):

78413P101

Names of Reporting Persons

Oppvest, LLC

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 677,971.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 677,971.00
8	Shared Dispositive Power 0.00

Aggregate Amount Beneficially Owned by Each Reporting Person

677,971.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

2.52 %

Type of Reporting Person (See Instructions)

OO, IA

SCHEDULE 13G

CUSIP Number(s):

78413P101

Names of Reporting Persons

Carl K. Oppenheimer

Check the appropriate box if a member of a Group (see instructions)

(a)

(b)

Sec Use Only

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 780,737.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 780,737.00
8	Shared Dispositive Power 0.00

Aggregate Amount Beneficially Owned by Each Reporting Person

1,412,618.00

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked

Percent of class represented by amount in row (9)

5.24 %

Type of Reporting Person (See Instructions)

SCHEDULE 13G

Item 1.

(a)

Name of issuer:

SEACOR Marine Holdings Inc.

(b)

Address of issuer's principal executive offices:

12121 Wickchester Lane, Suite 500, Houston, TEXAS 77079

Item 2.

(a)

Name of person filing:

P. Oppenheimer Investment Partnership, LP Oppenheimer-Close Investment Partnership, LP Oppenheimer + Close, LLC Oppvest, LLC Carl K. Oppenheimer

(b)

Address or principal business office or, if none, residence:

119 West 57th Street Suite 1515 New York, NY 10019

(c)

Citizenship:

Delaware Delaware Delaware Delaware USA

(d)

Title of class of securities:

Common Stock, par value $.01 per share

(e)

CUSIP Number(s):

78413P101

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:

530,010 147,961 734,647 677,971 1,412,618

(b)

Percent of class:

2.0% 0.6% 2.7% 2.5% 5.2%.

(c)

Number of shares as to which the person has:

(i) Sole power to vote or to direct the vote:

530,010 147,961 102,766 677,971 780,737

(ii) Shared power to vote or to direct the vote:

0 0 0 0 0

(iii) Sole power to dispose or to direct the disposition of:

530,010 147,961 102,766 677,971 780,737

(iv) Shared power to dispose or to direct the disposition of:

0 0 0 0 0

Item 5.

Ownership of 5 Percent or Less of a Class.

Not Applicable

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:

Not Applicable

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.

P. Oppenheimer Investment Parternship, LP

Signature:	Carl K. Oppenheimer
Name/Title:	Managing Member
Date:	04/21/2026

Oppenheimer-Close Investment Partnership, LP

Signature:	Carl K. Oppenheimer
Name/Title:	Managing Member
Date:	04/21/2026

Oppenheimer + Close, LLC

Signature:	Carl K. Oppenheimer
Name/Title:	Managing Member
Date:	04/21/2026

Oppvest, LLC

Signature:	Carl K. Oppenheimer
Name/Title:	Managing Member
Date:	04/21/2026

Carl K. Oppenheimer

Signature:	Carl K. Oppenheimer
Name/Title:	Managing Member
Date:	04/21/2026

SEC Form SCHEDULE 13G filed by SEACOR Marine Holdings Inc.