# EDGAR Filing Document

**Accession Number:** 0001999001
**File Stem:** 0001193125-26-124392
**Filing Date:** 2026-3
**Character Count:** 20275
**Document Hash:** e4130695f6e02d158084d170e81064f4
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-124392.hdr.sgml**: 20260325

**ACCESSION NUMBER**: 0001193125-26-124392

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 13

**CONFORMED PERIOD OF REPORT**: 20260324

**ITEM INFORMATION**: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20260325

**DATE AS OF CHANGE**: 20260325

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Six Flags Entertainment Corporation/NEW
- **CENTRAL INDEX KEY:** 0001999001
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-AMUSEMENT & RECREATION SERVICES [7900]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42157
- **FILM NUMBER:** 26793559

**BUSINESS ADDRESS:**
- **STREET 1:** 8701 RED OAK BLVD.
- **CITY:** CHARLOTTE
- **STATE:** NC
- **ZIP:** 28217
- **BUSINESS PHONE:** (419) 626-0830

**MAIL ADDRESS:**
- **STREET 1:** 8701 RED OAK BLVD.
- **CITY:** CHARLOTTE
- **STATE:** NC
- **ZIP:** 28217

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CopperSteel HoldCo, Inc.
- **DATE OF NAME CHANGE:** 20231027

?xml version='1.0' encoding='ASCII'? 8-K

### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### WASHINGTON, D.C. 20549

### FORM 8-K

#### CURRENT REPORT

#### PURSUANT TO SECTION 13 OR 15(d)

#### OF THE SECURITIES EXCHANGE ACT OF 1934

#### DATE OF REPORT (Date of earliest event reported): March 24, 2026

## Six Flags Entertainment Corporation

#### (Exact name of registrant as specified in its charter)

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-42157** | **93-4097909** |
| **(State or other jurisdiction**<br> **of incorporation)** | **(Commission**<br> **File Number)** | **(I.R.S. Employer**<br> **Identification No.)** |

---

#### 8701 Red Oak Blvd.

#### Charlotte, North Carolina 28217

#### (Address of principal executive offices) (Zip Code)
(704) 414-4700

#### (Registrant's telephone numbers, including area code)

#### (Former name or former address, if changed since last report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

---

| | | |
|:---|:---|:---|
| **Title of each class** | **Trading<br>Symbols** | **Name of each exchange<br>on which registered** |
| Common Stock, par value $0.01 per share | FUN | New York Stock Exchange |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

------

---

| | |
|:---|:---|
| **Item 5.02.** | **Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.**  |

---

On March 24, 2026, the Board of Directors (the "Board") of Six Flags Entertainment Corporation (the "Company") appointed Richard Haddrill as the Company's Executive Chair of the Board, effective immediately. Mr. Haddrill will serve as a Class II director, with a term expiring at the Company's 2026 Annual Meeting of Stockholders, and the Board will expand to 11 members. In connection with Mr. Haddrill's appointment, the Board has appointed Marilyn Spiegel to serve as Lead Independent Director of the Board.

Mr. Haddrill, age 72, is the founder and Chief Executive Officer of The Groop, LLC, an investment and advisory company he founded in January 2018. Mr. Haddrill is also the Vice Chairman of Generator Partners, an alternative energy and home electrification company he co-founded in 2024. He previously served as Executive Vice Chairman of Scientific Games Corporation (now Light & Wonder) from December 2014 to February 2018 and as Vice Chairman from February 2018 until August 2020. Prior to that, he served as Chief Executive Officer of Bally Technologies from October 2004 to December 2012 and again from May 2014 until Bally's acquisition by Scientific Games in November 2014, and served on Bally's board of directors from April 2003 until the acquisition, including as chairman from 2012 to 2014. He previously served as Chief Executive Officer of Manhattan Associates, Inc. beginning in October 1999 and later as Vice Chairman through May 2006. Earlier in his career, Mr. Haddrill served as CEO of Powerhouse Technologies, Inc. and as a Partner and Managing Partner at Ernst & Young LLP. Mr. Haddrill earned a B.S. from the University of Michigan.

In connection with Mr. Haddrill's appointment, on March 24, 2026, the Company entered into an employment agreement with Mr. Haddrill for a period of three years, with Mr. Haddrill serving for the first two years as Executive Chair and the final year as Executive Chair or Board Chair as mutually agreed upon by the Board of Directors and Mr. Haddrill. The employment agreement provides for, among other things, a base salary of $500,000 per year. The employment agreement also provides that Mr. Haddrill will receive a one-time equity grant on the date of commencement of employment comprised of (i) 217,797 restricted stock awards vesting in quarterly installments based on continued employment during the three-year term (the "Sign-on RSA Award") and (ii) 373,367 performance stock units with vesting based on achieving certain performance targets measured over a specified performance period (the "Sign-on PSU Award").

In the event of a termination by the Company without Cause or by Mr. Haddrill for Good Reason (each as defined in the employment agreement), Mr. Haddrill would be entitled to (i) pro-rated vesting of Sign-on RSA Awards and (ii) full vesting of Sign-on PSU Awards based on actual performance measured at the end of the performance period, with any performance-based shares earned as of the termination date accelerated. In the event of a termination for Cause or resignation without Good Reason, all PSUs are forfeited; for any other termination, the PSUs will continue to be eligible to vest in accordance with their terms. In the event that a termination without Cause or a resignation for Good Reason occurs within 18 months following a Change in Control (as defined in the employment agreement), Mr. Haddrill is entitled to full vesting of equity awards, with performance-based awards vesting based on actual performance measured through the date of the Change in Control, provided that no less than one-third of the Sign-on PSU Award (124,456 shares) shall vest. In the event of a resignation by Mr. Haddrill without Good Reason or termination by the Company for Cause, any shares previously issued in settlement of PSUs upon achievement of the applicable performance goals in the calendar year in which termination occurs are subject to clawback on a pro-rata basis, based on the number of days remaining in the calendar year in which the performance goal was achieved (if any), divided by 365. All termination payments and benefits under the employment agreement are subject to Mr. Haddrill signing a release of claims against the Company.

Under the terms of the employment agreement, Mr. Haddrill is subject to restrictive covenants, during and for specified periods following termination of employment, relating to non-solicitation of employees of the Company for two years following termination, as well as confidentiality restrictions and a non-disparagement covenant.

Mr. Haddrill has no family relationship with any directors or executive officers of the Company, nor are there any arrangements or understandings between Mr. Haddrill and any other persons pursuant to which he was selected as a director and Executive Chair of the Company. There are no transactions between Mr. Haddrill and the Company that would require disclosure under Item 404(a) of Regulation S-K.

------

The foregoing description of the employment agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the executed version of such agreement, a copy of which is to be filed as an exhibit to the Company's next Quarterly Report on Form 10-Q.

---

| | |
|:---|:---|
| **Item 7.01** | **Regulation FD Disclosure.**  |

---

On March 25, 2026, the Company issued a press release announcing the appointment of Mr. Haddrill as Executive Chair. A copy of the press release is attached as Exhibit 99.1 to this report and is incorporated by reference herein.

The information furnished pursuant to this Item 7.01, including Exhibit 99.1, shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and shall not be deemed to be incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

---

| | |
|:---|:---|
| **Item 9.01** | **Financial Statements and Exhibits.**  |

---

(d) Exhibits.

---

| | |
|:---|:---|
| **Exhibit<br>Number** | **Description** |
| 99.1 | [Press Release, dated March 25, 2026 (furnished herewith)](d20705dex991.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document) |

---

------

#### SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | | |
|:---|:---|:---|
| Date: March 25, 2026 | **SIX FLAGS ENTERTAINMENT CORPORATION** | **SIX FLAGS ENTERTAINMENT CORPORATION** |
|  | (Registrant) | (Registrant) |
|  | By: | /s/ Brian C. Witherow |
|  | Name: | Brian C. Witherow |
|  | Title: | Chief Financial Officer |

---

## Exhibit 99.1

**Exhibit 99.1**![LOGO](g20705g50a91.jpg)

**NEWS RELEASE** 

---

| | |
|:---|:---|
| **FOR IMMEDIATE RELEASE** | **Investor Contact: Michael Russell, 419.627.2233** |
| **https://investors.sixflags.com** | **Media Contact: Gary Rhodes, 704.249.6119** |

---

**SIX FLAGS ENTERTAINMENT APPOINTS RICHARD HADDRILL** 

**AS EXECUTIVE CHAIRMAN OF THE BOARD OF DIRECTORS** 

**CHARLOTTE, N.C. (Mar. 25, 2026)** – Six Flags Entertainment Corporation (NYSE: FUN) ("Six Flags" or the "Company"), North America's largest regional amusement park operator, today announced the appointment of Richard "Dick" Haddrill as Executive Chairman of the Six Flags Board of Directors, effective immediately. With Mr. Haddrill's appointment, Marilyn Spiegel will serve as Lead Independent Director.

Over the last several months, Six Flags has taken decisive actions to improve performance, including appointing John Reilly as CEO in December 2025, accelerating the Company's portfolio optimization and improving its capital structure. Haddrill's appointment continues Six Flags' efforts to refresh the composition of its Board and reinforce its commitment to ensuring the Board has the right mix of skills to oversee the Company's successful evolution. With Haddrill's appointment, Six Flags has added seven new directors to the Board since last summer.

Haddrill is a renowned public company executive with decades of experience in the entertainment and leisure industries. He previously served as Executive Vice Chairman of the Board of Scientific Games (now Light & Wonder), a leading provider of gaming and entertainment solutions and services. Before that, he served as Chief Executive Officer of Bally Technologies, where he led the company through significant growth and strategic transformation, culminating in its acquisition by Scientific Games. As Executive Chairman at Six Flags, Haddrill will focus on improving profitability while implementing strategic actions to drive long-term growth.

------

*SIX FLAGS ENTERTAINMENT APPOINTS RICHARD HADDRILL AS EXECUTIVE CHAIRMAN*

*March 25, 2026*

*Page 2*

"Dick is a proven leader with a strong track record of delivering outsized returns for shareholders," said Spiegel. "His strategic mindset, steady leadership, and decades of experience scaling and optimizing businesses will be invaluable as we continue to improve performance across the portfolio and enhance the guest experience. Dick's appointment reflects the Board's commitment to thoughtful refreshment to effectively oversee management's efforts to unlock the full value of Six Flags' world-class portfolio."

"On behalf of the management team and associates, we welcome Dick to Six Flags," said Reilly. "We look forward to working with him as we sharpen our focus on profitability and drive value creation for our guests and shareholders."

"Six Flags is an incredible business, and I believe in the steps John Reilly and the management team are taking to strengthen execution and realize the full potential of the irreplaceable Six Flags portfolio," said Haddrill. "I am excited to work closely with John, the rest of the Six Flags Board, and the management team to continue building on their progress."

With Haddrill's addition, the Board will temporarily expand to 11 members. As previously disclosed, Jennifer Mason will not stand for re-election when her term expires at the Company's 2026 Annual Meeting of Stockholders, at which point the Board size will revert to 10 members.

**<u>About Richard Haddrill</u>**

Richard Haddrill is the Founder and CEO of The Groop, LLC, an investment and advisory company, and founder and Vice Chairman of Generator Partners, an alternative energy and home electrification company. He was previously Executive Vice Chairman of Scientific Games, where he oversaw the integration of Bally Technologies and the expansion and evolution of Scientific Games' portfolio. Prior to that, he served as CEO of Bally Technologies, where he increased revenue from $550 million to $1.2 billion and the share price by 7x over the eight years prior to Bally's acquisition by Scientific Games in 2014. He previously served as Chief Executive Officer of Manhattan Associates, Inc., where he increased the company's revenues by 150% and its share price by 8x in a five-year span. Haddrill has served on numerous private and public company boards and, earlier in his career, was a Partner and Managing Partner at Ernst & Young, where he served as National Director of Entrepreneurial Services. He earned a BS in Business Administration from the University of Michigan.

------

*SIX FLAGS ENTERTAINMENT APPOINTS RICHARD HADDRILL AS EXECUTIVE CHAIRMAN*

*March 25, 2026*

*Page 3*

**<u>About Six Flags Entertainment Corporation</u>**

Six Flags Entertainment Corporation (NYSE: FUN) is North America's largest regional amusement-resort operator, with 26 amusement parks, 15 water parks and nine resort properties across 16 states in the U.S., Canada, and Mexico. The Company also manages an amusement park in Saudi Arabia. Focused on its purpose of making people happy, Six Flags provides fun, immersive and memorable experiences to millions of guests every year with world-class coasters, themed rides, thrilling water parks, resorts and a portfolio of beloved intellectual property such as Looney Tunes<sup>®</sup>, DC Comics<sup>®</sup> and PEANUTS<sup>®</sup>.

**<u>Forward-Looking Statements</u>**

Some of the statements contained in this news release that are not historical in nature are forward-looking statements within the meaning of the federal securities laws, including Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, including statements as to our expectations, beliefs, goals and strategies regarding the future. Words such as "anticipate," "believe," "create," "expect," "future," "guidance," "intend," "plan," "potential," "seek," "synergies," "target," "objective," "will," "would," similar expressions, and variations or negatives of these words identify forward-looking statements. However, the absence of these words does not mean that the statements are not forward-looking. Forward-looking statements by their nature address matters that are, to different degrees, uncertain. These forward-looking statements may involve current plans, estimates, expectations and ambitions that are subject to risks, uncertainties and assumptions that are difficult to predict, may be beyond our control and could cause actual results to differ materially from those described in such statements. Although we believe that the expectations reflected in such forward-looking statements are reasonable, we can give no assurance that such expectations will prove to be correct, or that our growth and operational strategies will achieve the target results. Important risks and uncertainties that may cause such a difference and could adversely affect attendance at our parks, our future financial performance, and/or our growth strategies, and could cause actual results to differ materially from our expectations or otherwise to fluctuate or decrease, include, but are not limited to: failure to realize the anticipated benefits of the merger, including difficulty in integrating the businesses of legacy Six Flags and legacy Cedar Fair; failure to realize the expected amount and timing of cost savings and operating synergies related to the merger; adverse weather conditions; general economic, political and market conditions, including global trade; the impacts of pandemics or other public health crises, including the effects of government responses on people and economies;

------

*SIX FLAGS ENTERTAINMENT APPOINTS RICHARD HADDRILL AS EXECUTIVE CHAIRMAN*

*March 25, 2026*

*Page 4*

competition for consumer leisure time and spending or other changes in consumer behavior or sentiment for discretionary spending; unanticipated construction delays or increases in construction or supply costs; changes in capital investment plans and projects; anticipated tax treatment, unforeseen liabilities, future capital expenditures, revenues, expenses, earnings, synergies, economic performance, indebtedness, financial condition, losses, future prospects, business and management strategies for the management, expansion and growth of our operations; the impact of any potential shareholder activism; failure to attract, motivate and retain qualified domestic and international employees and key personnel; legislative, regulatory and economic developments and changes in laws, regulations, and policies affecting us; acts of terrorism or outbreak of war, hostilities, civil unrest, and other political or security disturbances; and other risks and uncertainties we discuss under the heading "Risk Factors" within our Annual Report on Form 10-K and in the other filings we make from time to time with the Securities and Exchange Commission. Readers are urged not to place undue reliance on these forward-looking statements, which speak only as of the date of this document and are based on information currently and reasonably known to us. We do not undertake any obligation to publicly update or revise any forward-looking statements to reflect future events, information or circumstances that arise after publication of this news release.

*This news release and prior releases are available under the News tab at <u>https://investors.sixflags.com</u>* 

*# # #*