FMR LLC holds 3.72M Marex (NASDAQ: MRX) shares — 5.1% stake

Rhea-AI Filing Summary

FMR LLC reports beneficial ownership of 3,724,911 shares of Marex Group PLC common stock, equal to 5.1% of the class as of 03/31/2026. The filing states FMR LLC holds sole dispositive power over 3,724,911 shares and sole voting power of 3,720,946 shares; Abigail P. Johnson is identified with dispositive authority.

Insights

Institutional Ownership Analyst

Large passive stake disclosed by a major asset manager; holdings exceed the 5% reporting threshold.

FMR LLC's Schedule 13G reports beneficial ownership of 3,724,911 shares, representing 5.1% of Marex Group PLC as of 03/31/2026. The filing attributes sole dispositive power to FMR LLC and lists Abigail P. Johnson with dispositive authority.

Such a 13G filing indicates a passive investor classification under Schedule 13G conditions; subsequent Form 13D or material changes would alter reporting status and should appear in future SEC filings.

Key Figures

Beneficial ownership: 3,724,911 shares Percent of class: 5.1% Sole voting power: 3,720,946 shares +3 more

6 metrics

Beneficial ownership 3,724,911 shares as of 03/31/2026

Percent of class 5.1% ownership percentage reported on Schedule 13G

Sole voting power 3,720,946 shares sole power to vote reported on cover page

Sole dispositive power 3,724,911 shares sole power to dispose reported on cover page

CUSIP G5S37H101 Marex Group PLC common stock identifier

Signature date 05/05/2026 filing signatures dated

Key Terms

Schedule 13G, Beneficial ownership, Sole dispositive power, Power of Attorney

4 terms

Schedule 13G regulatory

"Item 1. (a) Name of issuer: MAREX GROUP PLC"

A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.

Beneficial ownership financial

"Item 4. (a) Amount beneficially owned: 3724911.00"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

Sole dispositive power regulatory

"Item 4. (iii) Sole power to dispose: 3724911.00"

Sole dispositive power is the exclusive legal authority to decide what happens to a security — for example, whether to sell, transfer, or retain shares — without needing anyone else’s permission. Investors care because it signals who truly controls the economic outcome of an investment: like holding the only key to a safe, the holder can realize gains or losses and may trigger regulatory reporting, insider rules, or influence over corporate ownership.

Power of Attorney legal

"Duly authorized under Power of Attorney effective as of April 13, 2026"

A power of attorney is a legal document that allows one person to make decisions and act on behalf of another person, often in financial or legal matters. It’s like giving someone a trusted helper or agent the authority to handle important tasks if you are unable to do so yourself. This matters to investors because it can impact how their assets are managed or transferred if they become unable to oversee their affairs.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

MAREX GROUP PLC

(Name of Issuer)

COMMON STOCK

(Title of Class of Securities)

G5S37H101

(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)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): G5S37H101

1

Names of Reporting Persons

FMR 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 3,720,946.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 3,724,911.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,724,911.00

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)

5.1 %

12

Type of Reporting Person (See Instructions)

HC

SCHEDULE 13G

CUSIP Number(s): G5S37H101

1

Names of Reporting Persons

Abigail P. Johnson

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 0.00
7	Sole Dispositive Power 3,724,911.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,724,911.00

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)

5.1 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: MAREX GROUP PLC
(b)	Address of issuer's principal executive offices: 155 BISHOPSGATE,LONDON,X0,EC2M 3TQ
Item 2.
(a)	Name of person filing: FMR LLC
(b)	Address or principal business office or, if none, residence: 245 Summer Street, Boston, Massachusetts 02210
(c)	Citizenship: Not applicable
(d)	Title of class of securities: COMMON STOCK
(e)	CUSIP Number(s): G5S37H101
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: 3724911.00
(b)	Percent of class: 5.1 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: Please see the responses to Items 5 and 6 on the cover page.
	(ii) Shared power to vote or to direct the vote: 0.00
	(iii) Sole power to dispose or to direct the disposition of: 3724911.00
	(iv) Shared power to dispose or to direct the disposition of: 0.00
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.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. One or more other persons are known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the COMMON STOCK of MAREX GROUP PLC. No one other person's interest in the COMMON STOCK of MAREX GROUP PLC is more than five percent of the total outstanding COMMON STOCK.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. See attached Exhibit 99.
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 acquired and are held in the ordinary course of business and 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.

FMR LLC

Signature:	Richard Bourgelas
Name/Title:	Duly authorized under Power of Attorney effective as of April 13, 2026, by and on behalf of FMR LLC and its direct and indirect subsidiaries*
Date:	05/05/2026

Abigail P. Johnson

Signature:	Richard Bourgelas
Name/Title:	Duly authorized under Power of Attorney effective as of April 13, 2026, by and on behalf of Abigail P. Johnson*
Date:	05/05/2026

Comments accompanying signature: *This power of attorney is incorporated herein by reference to Exhibit 24 to the Schedule 13G filed by FMR LLC on April 29,2026, accession number: 0000315066-26-000738.

Exhibit Information

Please see Exhibit 99 for 13d-1(k) (1) agreement.

FAQ

What stake does FMR LLC report in Marex Group (MRX)?

FMR LLC reports owning 3,724,911 shares (5.1%). The Schedule 13G lists this amount as beneficial ownership as of 03/31/2026 and discloses sole dispositive power over all 3,724,911 shares.

Does the filing show who controls the voting or disposition of MRX shares?

Yes. The filing states FMR LLC has sole dispositive power over 3,724,911 shares and sole voting power of 3,720,946 shares, and it identifies Abigail P. Johnson as having dispositive authority on behalf of the reporting group.

Is this a Schedule 13G or 13D filing for MRX and what does that mean?

This is a Schedule 13G filing. Schedule 13G is used by investors claiming passive status once ownership crosses the 5% threshold; it reflects reported beneficial ownership without asserting activist intent in the provided excerpt.

As of what date are the ownership figures reported for MRX?

The ownership figures are reported as of 03/31/2026. The Schedule 13G lists 3,724,911 shares and a 5.1% ownership percentage tied to that date in the filing excerpt.

Who signed the Schedule 13G for FMR LLC regarding MRX?

Richard Bourgelas signed on behalf of FMR LLC and Abigail P. Johnson. Signatures reference a power of attorney effective April 13, 2026, and are dated 05/05/2026 in the filing excerpt.