AQR discloses 6.88% passive MarketAxess (MKTX) ownership stake

Rhea-AI Filing Summary

AQR Capital Management, LLC and AQR Capital Management Holdings, LLC report a passive ownership stake in MarketAxess Holdings Inc. They beneficially own 2,558,097 shares of MarketAxess common stock, representing 6.88% of the class. Both entities have shared voting and shared dispositive power over these shares, with no sole voting or dispositive authority.

The firms state the shares were acquired and are held in the ordinary course of business, and not for the purpose of changing or influencing control of MarketAxess. AQR Capital Management, LLC is a wholly owned subsidiary of AQR Capital Management Holdings, LLC.

Insights

Equity ownership analyst

AQR and its parent report a 6.88% passive stake in MarketAxess, with shared voting and dispositive power.

AQR Capital Management, LLC and its parent, AQR Capital Management Holdings, LLC, disclose beneficial ownership of 2,558,097 MarketAxess shares, equal to 6.88% of the common stock. Both entities report zero sole voting or dispositive power and instead share these rights over the same share block.

The ownership is described as being held in the ordinary course of business, without intent to change or influence control. This aligns with a passive institutional investment profile rather than an activist position. AQR Capital Management, LLC is noted as a wholly owned subsidiary of AQR Capital Management Holdings, LLC, clarifying the control structure over the reported holdings.

The information primarily signals institutional interest rather than a strategic control move. Future ownership levels or changes, if any, would typically appear in subsequent beneficial ownership disclosures from these or other large shareholders.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

MARKETAXESS HOLDINGS INC

(Name of Issuer)

Common Stock, $0.003 par value

(Title of Class of Securities)

57060D108

(CUSIP Number)

12/31/2025

(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 No. 57060D108

1

Names of Reporting Persons

AQR Capital Management, 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

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 2,558,097.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,558,097.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,558,097.00

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)

6.88 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

CUSIP No. 57060D108

1

Names of Reporting Persons

AQR Capital Management Holdings, 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

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 2,558,097.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,558,097.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,558,097.00

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)

6.88 %

12

Type of Reporting Person (See Instructions)

HC

SCHEDULE 13G

Item 1.
(a)	Name of issuer: MARKETAXESS HOLDINGS INC
(b)	Address of issuer's principal executive offices: 55 HUDSON YARDS, 15TH FLOOR, NEW YORK, NEW YORK 10001
Item 2.
(a)	Name of person filing: AQR Capital Management, LLC AQR Capital Management Holdings, LLC
(b)	Address or principal business office or, if none, residence: ONE GREENWICH PLAZA SUITE 130 Greenwich, Connecticut 06830
(c)	Citizenship: AQR Capital Management, LLC - UNITED STATES AQR Capital Management Holdings, LLC - UNITED STATES
(d)	Title of class of securities: Common Stock, $0.003 par value
(e)	CUSIP No.: 57060D108
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: 2,558,097
(b)	Percent of class: 6.88 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: AQR Capital Management, LLC - 0 AQR Capital Management Holdings, LLC - 0
	(ii) Shared power to vote or to direct the vote: AQR Capital Management, LLC - 2,558,097 AQR Capital Management Holdings, LLC - 2,558,097
	(iii) Sole power to dispose or to direct the disposition of: AQR Capital Management, LLC - 0 AQR Capital Management Holdings, LLC - 0
	(iv) Shared power to dispose or to direct the disposition of: AQR Capital Management, LLC - 2,558,097 AQR Capital Management Holdings, LLC - 2,558,097
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.
	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 Item 2(a) above.
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.

AQR Capital Management, LLC

Signature:	Henry Parkin
Name/Title:	Authorized Signatory
Date:	02/13/2026

AQR Capital Management Holdings, LLC

Signature:	Henry Parkin
Name/Title:	Authorized Signatory
Date:	02/13/2026

Exhibit Information

AQR Capital Management Holdings, LLC and AQR Capital Management, LLC hereby agree that this Schedule 13G is filed on behalf of each of the parties. AQR Capital Management, LLC is a wholly owned subsidiary of AQR Capital Management Holdings, LLC.

FAQ

What stake in MarketAxess (MKTX) does AQR report owning?

AQR reports beneficial ownership of 2,558,097 MarketAxess shares, equal to 6.88% of the common stock. This stake is held with shared voting and shared dispositive power by AQR Capital Management, LLC and its parent, AQR Capital Management Holdings, LLC.

Is AQR’s MarketAxess (MKTX) position an activist or passive stake?

AQR characterizes its MarketAxess position as a passive stake held in the ordinary course of business. The firms state the shares were not acquired, and are not held, to change or influence control of MarketAxess or participate in control-related transactions.

How much voting power does AQR have over MarketAxess (MKTX) shares?

AQR reports zero sole voting power and 2,558,097 shares of shared voting power in MarketAxess. Both AQR Capital Management, LLC and AQR Capital Management Holdings, LLC share the ability to vote or direct the vote for this 6.88% ownership block.

Who are the reporting persons for the MarketAxess (MKTX) ownership disclosure?

The reporting persons are AQR Capital Management, LLC and its parent, AQR Capital Management Holdings, LLC. Both are organized in the United States and report the same 2,558,097 MarketAxess shares with shared voting and shared dispositive power over the common stock position.

Does AQR have sole dispositive power over its MarketAxess (MKTX) shares?

AQR reports no sole dispositive power over MarketAxess shares, only shared dispositive authority. Both AQR Capital Management, LLC and AQR Capital Management Holdings, LLC list 2,558,097 shares over which they share the power to dispose or direct the disposition of the common stock.

What type of MarketAxess (MKTX) security does AQR hold?

AQR holds MarketAxess common stock with a par value of $0.003 per share, identified by CUSIP 57060D108. The reported position totals 2,558,097 common shares, representing 6.88% of this class of MarketAxess equity securities as of the reported ownership date.