Key facts
- This page summarizes Jonathan A. Brudnick's Form 3 filing for Six Flags Entertainment Corporation/NEW (FUN).
- 0 reported transactions and 3 derivative rows are listed below.
- Accepted by SEC: 27 Oct 2025, 18:29.
Jonathan A. Brudnick - 17 Oct 2025 Form 3 Insider Report for Six Flags Entertainment Corporation/NEW (FUN)
- Reporting relationship
- Director
- Issuer ticker
- FUN
- Reported as of
- 17 Oct 2025
- Net transaction value
- $0
- Reporting owner signature
- /s/ Michael D. Adamski, as Attorney-in-Fact
Source evidence
Original filing metadata and source links for verification.
3 source fields
Reporting owner
1 detail
Key filing fact
Jonathan A. Brudnick filed Form 3 for Six Flags Entertainment Corporation/NEW (FUN) on 27 Oct 2025.
Change
- No earlier filing in this sequence is available for direct comparison.
- Current net transaction value: $0.
Research use
- This tells you what this filing adds before you inspect full transaction and derivative tables.
- You can trace every row back to the original SEC filing document.
Evidence
Official SEC source
View source filing
Ownership activity is grounded in SEC Form 3 disclosures.
Reporting Owners (5)
CIK 0002092404
Primary reporting owner
Brudnick Jonathan A.
- Relationship
- Director
- Address
- 250 WEST 55TH STREET,, FLOOR 34, NEW YORK
- Signature
- /s/ Michael D. Adamski, as Attorney-in-Fact
- Signature date
- 27 Oct 2025
CIK 0001658919
Ferguson Scott D.
- Relationship
- Director
- Address
- 250 WEST 55TH STREET,, FLOOR 34, NEW YORK
- Signature
- /s/ Michael D. Adamski, as Attorney-in-Fact
- Signature date
- 27 Oct 2025
CIK 0001582090
Sachem Head Capital Management LP
- Relationship
- Director
- Address
- 250 WEST 55TH STREET,, FLOOR 34, NEW YORK
- Signature
- /s/ Michael D. Adamski, as General Counsel
- Signature date
- 27 Oct 2025
CIK 0001658906
Uncas GP LLC
- Relationship
- Director
- Address
- 250 WEST 55TH STREET,, FLOOR 34, NEW YORK
- Signature
- /s/ Michael D. Adamski, as General Counsel
- Signature date
- 27 Oct 2025
CIK 0001658917
Sachem Head GP LLC
- Relationship
- Director
- Address
- 250 WEST 55TH STREET,, FLOOR 34, NEW YORK
- Signature
- /s/ Michael D. Adamski, as General Counsel
- Signature date
- 27 Oct 2025
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
FUN
holding
Common Stock, par value $0.01 per share
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- 5,030,000
- Date
- 17 Oct 2025
- Ownership
- See footnotes
- Footnotes
- F1, F2, F3, F4
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
FUN
holding
Derivative
Cash Settled Swap
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- Date
- 17 Oct 2025
- Ownership
- See footnotes
- Underlying class
- Common Stock
- Underlying amount
- 2,209,648
- Exercise price
- $28.69
- Footnotes
- F1, F2, F3, F4, F5, F6
FUN
holding
Derivative
Cash Settled Swap
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- Date
- 17 Oct 2025
- Ownership
- See footnotes
- Underlying class
- Common Stock
- Underlying amount
- 1,605,352
- Exercise price
- $28.61
- Footnotes
- F1, F2, F3, F4, F5, F6
FUN
holding
Derivative
Cash Settled Swap
No transaction description listed
- Transaction value
- Shares
- Change %
- Price
- Shares after
- Date
- 17 Oct 2025
- Ownership
- See footnotes
- Underlying class
- Common Stock
- Underlying amount
- 1,180,000
- Exercise price
- $29.06
- Footnotes
- F1, F2, F3, F4, F5, F6
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Explanation of responses 6 footnotes
Footnote F1
In addition to Jonathan Brudnick, this Form 3 is being filed jointly by Sachem Head Capital Management LP ("Sachem Head"), Uncas GP LLC ("SH Management"), Sachem Head GP LLC ("Sachem Head GP"), and Scott D. Ferguson, a citizen of the United States (Mr. Ferguson and, together with Sachem Head, SH Management, Sachem GP, and Mr. Brudnick, the "Reporting Persons"). Each of the Reporting Persons has the same business address as Mr. Brudnick and may be deemed to be the beneficial owner of certain of the securities reported on this Form 3 (the "Subject Securities") for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended. Each of the Reporting Persons disclaims any beneficial ownership of any of the Subject Securities, except to the extent of any pecuniary interest therein.
Footnote F2
Includes securities directly owned by Sachem Head LP ("SH"), Sachem Head Master LP ("SHM"), and SH Stony Creek Master Ltd. ("Stony Creek Master" and, together with SH and SHM, the "Sachem Head Funds"). Each of Sachem Head, as the investment adviser to the Sachem Head Funds, SH Management, as the sole general partner of Sachem Head, and Scott D. Ferguson, as the managing partner of Sachem Head may be deemed to beneficially own the securities directly owned by the Sachem Head Funds. As the general partner of SH and SHM, Sachem Head GP may be deemed to beneficially own the securities directly owned by SH and SHM.
Footnote F3
The principal business of Sachem Head is to serve as investment advisor to certain affiliated funds, including the Sachem Head Funds. The principal business of SH Management is to serve as the sole general partner of Sachem Head. The principal business of Sachem Head GP is to serve as the general partner of certain affiliated funds, including SH and SHM. The principal occupation of Scott D. Ferguson is to serve as the managing partner of Sachem Head and the managing member of SH Management and Sachem Head GP.
Footnote F4
Jonathan Brudnick is a partner at Sachem Head and also serves on the board of directors of Six Flags Entertainment Corporation (the "Issuer"). As a result, the Reporting Persons other than Mr. Brudnick may be deemed directors of the Issuer by deputization.
Footnote F5
Under the cash-settled total return swaps referencing in the aggregate 4,995,000 shares of common stock (the "Cash Settled Swaps"), the respective Sachem Head Fund became a party to contracts with unaffiliated third party financial institutions pursuant to which a cash payment will be made by the counterparty to the respective Sachem Head Fund if the price of a share on the expiration date exceeds the reference price in column 4 and a cash payment will be made by the respective Sachem Head Fund to the counterparty if the price of a share on the expiration date is less than the reference price in column 4.
Footnote F6
The Cash Settled Swaps do not give any Reporting Person direct or indirect voting, investment or dispositive control over any securities of the Issuer and do not require the counterparty thereto to acquire, hold, vote or dispose of any securities of the Issuer. Accordingly, the Reporting Persons disclaim any beneficial ownership of any Shares that may be referenced in the swap contracts or shares or other securities or financial instruments that may be held from time to time by any counterparty to the contracts.
SEC remarks
Exhibit 24.1 - Power of Attorney. Exhibit 24.2 - Power of Attorney.