Plains All American Appoints Dean Liollio as EVP & COO Following Chris Chandler's Resignation

Executive Transition Summary

On September 29, 2026, Plains All American Pipeline, L.P. (NASDAQ: PAA) and Plains GP Holdings, L.P. (NASDAQ: PAGP) announced the appointment of Dean Liollio as Executive Vice President and Chief Operating Officer of their general partners, effective October 2, 2026.

Mr. Liollio replaces Chris Chandler, who gave notice on September 25, 2026, of his resignation effective October 2, 2026, in order to pursue other interests. The filing confirms that Mr. Chandler’s resignation is not related to any disagreement with the partnership on matters relating to operations, policies, or practices.

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Appointee Profile: Dean Liollio

• Age: 67
• Recent Experience:
  • Senior Vice President, Special Projects, Plains (June 2024 – October 2026)
  • President, Plains Midstream Canada (2020 – 2024)
  • President, PAA Natural Gas Storage (2008 – 2020)
  • President, Plains Gas Solutions (2016 – 2020)
  • Prior executive roles: President, CEO & Director of EnergySouth, Inc.; President & COO of CenterPoint Energy's natural gas distribution operations across five states.
• Education: B.S. in Industrial Engineering from Texas A&M University.

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Compensatory Arrangements

In connection with his appointment as EVP and COO, Mr. Liollio's compensation terms include:

• Base Salary: $625,000 annually.
• Annual Bonus Target: 150% of annual base salary.
• Long-Term Incentive Plan (LTIP): Promotional grant of 150,000 phantom units subject to time-based vesting through August 2029.

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Corporate & Governance Context

• The filing affirms there are no family relationships between Mr. Liollio and any director or executive officer of Plains.
• There are no related-party transactions or arrangements under which Mr. Liollio was selected.
• A concurrent press release was issued under Item 7.01 and furnished as Exhibit 99.1.