Morgan Stanley units hold 5.4% of Six Flags (NYSE: FUN) in amended 13G

Rhea-AI Filing Summary

Six Flags Entertainment Corporation ownership disclosure: Morgan Stanley and Morgan Stanley Capital Services LLC filed Amendment No. 2 to a Schedule 13G/A reporting passive ownership stakes in Six Flags common stock. The filing lists 5,514,103 shares (5.4%) attributed to Morgan Stanley reporting units and 5,371,530 shares (5.3%) attributed to Morgan Stanley Capital Services LLC. The filing is signed by an authorized Morgan Stanley representative on 05/12/2026 and includes a joint filing agreement and an Item 7 exhibit describing the relevant subsidiary information.

Insights

Institutional Ownership Analyst

Morgan Stanley reports low‑single‑digit passive stakes in Six Flags.

The filing is an amended Schedule 13G/A showing beneficial ownership by Morgan Stanley reporting units: 5,514,103 shares (5.4%) and by Morgan Stanley Capital Services LLC: 5,371,530 shares (5.3%). The percentages indicate passive investor status under the schedule and do not imply control.

Future filings may disclose changes in holdings; timing and trading activity are not included in this excerpt.

Securities Compliance Counsel

Amendment and exhibits align with Schedule 13G procedural requirements.

The amendment includes a Joint Filing Agreement and Item 7 exhibit as required for parent/subsidiary disclosures and cites the Release No. 34-39538 allocation approach. It is signed and dated 05/12/2026.

This filing classifies the positions as passive and lists shared voting/dispositive power amounts; no regulatory action or settlement language appears in the excerpt.

Key Figures

Morgan Stanley shares: 5,514,103 shares Morgan Stanley % ownership: 5.4% MS Capital Services shares: 5,371,530 shares

3 metrics

Morgan Stanley shares 5,514,103 shares reported by Morgan Stanley reporting units

Morgan Stanley % ownership 5.4% percent of class reported in Item 4(b)

MS Capital Services shares 5,371,530 shares reported by Morgan Stanley Capital Services LLC

Key Terms

Schedule 13G/A, Shared Dispositive Power, Joint Filing Agreement

3 terms

Schedule 13G/A regulatory

"Amendment No. 2 to a Schedule 13G/A reporting beneficial ownership"

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.

Shared Dispositive Power financial

"Shared Dispositive Power 5,514,103.00"

Joint Filing Agreement regulatory

"EXHIBIT NO. 99.1 Joint Filing Agreement"

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 2)

Six Flags Entertainment Corporation/NEW

(Name of Issuer)

Common Stock

(Title of Class of Securities)

83001C108

(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): 83001C108

1

Names of Reporting Persons

Morgan Stanley

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 5,447,918.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,514,103.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,514,103.00

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)

5.4 %

12

Type of Reporting Person (See Instructions)

HC, CO

SCHEDULE 13G

CUSIP Number(s): 83001C108

1

Names of Reporting Persons

Morgan Stanley Capital Services 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 5,371,530.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,371,530.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,371,530.00

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)

5.3 %

12

Type of Reporting Person (See Instructions)

BD, CO

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Six Flags Entertainment Corporation/NEW
(b)	Address of issuer's principal executive offices: 8701 RED OAK BLVD., CHARLOTTE, NC, 28217
Item 2.
(a)	Name of person filing: 1: Morgan Stanley 2: Morgan Stanley Capital Services LLC
(b)	Address or principal business office or, if none, residence: 1: 1585 Broadway, New York, NY 10036 ;2: 1585 Broadway, New York, NY 10036
(c)	Citizenship: 1: Delaware 2: Delaware
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 83001C108
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: See the response(s) to Item 9 on the attached cover page(s).
(b)	Percent of class: 5.4 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: See the response(s) to Item 5 on the attached cover page(s).
	(ii) Shared power to vote or to direct the vote: See the response(s) to Item 6 on the attached cover page(s).
	(iii) Sole power to dispose or to direct the disposition of: See the response(s) to Item 7 on the attached cover page(s).
	(iv) Shared power to dispose or to direct the disposition of: See the response(s) to Item 8 on the attached cover page(s).
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 Exhibit 99.2
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. * In Accordance with the Securities and Exchange Commission Release No. 34-39538 (January 12, 1998) (the "Release"), this filing reflects the securities beneficially owned, or that may be deemed to be beneficially owned, by certain operating units (collectively, the "MS Reporting Units") of Morgan Stanley and its subsidiaries and affiliates (collectively, "MS"). This filing does not reflect securities, if any, beneficially owned by any operating units of MS whose ownership of securities is disaggregated from that of the MS Reporting Units in accordance with the Release.

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.

Morgan Stanley

Signature:	Claire Gordon
Name/Title:	Authorized Signatory, Morgan Stanley
Date:	05/12/2026

Morgan Stanley Capital Services LLC

Signature:	Claire Gordon
Name/Title:	Authorized Signatory, Morgan Stanley Capital Services LLC
Date:	05/12/2026

Exhibit Information

EXHIBIT NO. EXHIBITS ------------------ ------------------------------------ 99.1 Joint Filing Agreement 99.2 Item 7 Information * Attention. Intentional misstatements or omissions of fact constitute federal criminal violations (see 18 U.S.C. 1001).

FAQ

What stake in Six Flags (FUN) does Morgan Stanley report?

Morgan Stanley's reporting units are shown as holding 5,514,103 shares (5.4%). The Schedule 13G/A amendment attributes shared voting and dispositive power to Morgan Stanley reporting units as disclosed in the cover responses.

What stake in Six Flags (FUN) does Morgan Stanley Capital Services LLC report?

Morgan Stanley Capital Services LLC is reported as holding 5,371,530 shares (5.3%). The filing shows shared voting and dispositive power for that entity on the attached cover page.

When was the Schedule 13G/A amendment signed for FUN?

The amendment is signed by an authorized Morgan Stanley signatory on 05/12/2026. The filing identifies the parties and includes exhibits 99.1 (Joint Filing Agreement) and 99.2 (Item 7 subsidiary information).

Does this Schedule 13G/A indicate active control or a passive stake in FUN?

The filing is a Schedule 13G/A amendment, which typically reports passive beneficial ownership. The document lists shared voting/dispositive power amounts but classifies holdings under the Schedule 13G framework rather than control-focused forms.

What exhibits accompany the FUN Schedule 13G/A amendment?

The filing attaches at least two exhibits: 99.1 Joint Filing Agreement and 99.2 Item 7 Information, the latter providing subsidiary identification and classification as referenced in the cover page.