Form 8-K

8-K — PLAINS ALL AMERICAN PIPELINE LP

Accession: 0001104659-26-111950

Filed: 2026-09-29

Period: 2026-09-25

CIK: 0001070423

SIC: 4610 (PIPE LINES (NO NATURAL GAS))

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — tm2626533d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2626533d1_ex99-1.htm)

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PLAINS ALL AMERICAN PIPELINE LP

0001070423

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PLAINS

ALL AMERICAN PIPELINE LP

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):

September 25, 2026

Plains All American Pipeline,

L.P.

(Exact name of registrant as specified in its

charter)

Delaware

1-14569

76-0582150

(State

or other jurisdiction of incorporation)

(Commission

File Number)

(IRS

Employer Identification No.)

333

Clay Street, Suite 1600,

Houston, Texas

77002

(Address of principal executive offices) (Zip

Code)

Registrant’s telephone number, including

area code: 713-646-4100

(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 Symbol(s)

Name of each exchange on which

registered

Common

Units

PAA

The Nasdaq Global Select Market

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

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 September 29, 2026, Plains All American Pipeline,

L.P. (“PAA” or the “Registrant”) and Plains GP Holdings, L.P. (“PAGP”) announced the appointment,

effective October 2, 2026, of Dean Liollio as Executive Vice President and Chief Operating Officer (“EVP and COO”) of Plains

All American GP LLC, the general partner of PAA, and PAA GP Holdings LLC, the general partner of PAGP. Chris Chandler, who previously

served as EVP and COO of PAA and PAGP, provided notice on September 25, 2026 that he will resign from the company effective October 2,

2026. Mr. Chandler is resigning to pursue other interests and not due to any disagreement relating to the company’s operations,

policies or practices.

Mr. Liollio, age 67, served as Senior Vice President,

Special Projects, of Plains from June 2024 until his appointment as EVP and COO in October 2026. He previously served as President

of Plains Midstream Canada from 2020 until 2024, as President of PAA Natural Gas Storage from 2008 until 2020 and as President of Plains

Gas Solutions from 2016 until 2020. Prior to joining Plains in 2008, Mr. Liollio held a number of executive roles including serving as

President, Chief Executive Officer and Director of EnergySouth, Inc. and as President and Chief Operating Officer of Centerpoint's natural

gas distribution operations across a five-state area including Houston. Mr. Liollio holds a Bachelor of Science degree in Industrial Engineering from Texas A&M University.

As EVP and COO, Mr. Liollio will receive an annual

base salary of $625,000. His annual bonus target (expressed as a percentage of base salary) will be 150% and he will receive a time-based

promotional LTIP grant for 150,000 phantom units vesting in August 2029. Information regarding our executive compensation program is included

in our annual proxy statement.

There is no family relationship between Mr. Liollio

and any executive officer or director of Plains and there are no understandings or arrangements between Mr. Liollio and any other person

pursuant to which Mr. Liollio was appointed as EVP and COO.

Item 7.01. Regulation FD Disclosure.

On September 29, 2026, Plains issued a press release

announcing these events. A copy of the news release is furnished as Exhibit 99.1 hereto and incorporated by reference herein.

In accordance with General

Instruction B.2 of Form 8-K, the information presented herein under Item 7.01 shall not be deemed “filed” for the purpose

of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such

information be deemed incorporated by reference into any filing under the Securities Act of 1933 or the Securities Exchange Act of 1934,

each as amended.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

Number

Description

99.1

Press Release dated September 29, 2026.

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.

PLAINS ALL AMERICAN PIPELINE, L.P.

Date: September 29, 2026

By:

PAA GP LLC, its general partner

By:

Plains AAP, L.P., its sole member

By:

Plains All American GP LLC, its general partner

By:

/s/ Richard McGee

Name:

Richard McGee

Title:

Executive Vice President, General Counsel and Secretary

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2626533d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Plains All American Pipeline and Plains GP Holdings

Announce Appointment of New Chief Operating Officer

HOUSTON – [September 29, 2026] – Plains All American Pipeline,

L.P. (Nasdaq: PAA) and Plains GP Holdings (Nasdaq: PAGP) (collectively, “Plains”) announced that Dean Liollio

has been appointed to serve as Executive Vice President and Chief Operating Officer of Plains effective as of October 2, 2026. Mr. Liollio

replaces Chris Chandler, the current EVP and COO, who is resigning from Plains to pursue other interests and not due to any disagreement

relating to the company’s operations, policies or practices.

Mr. Liollio, age 67, served as Senior Vice President, Special Projects,

of Plains from June 2024 until his appointment as EVP and COO in October 2026. He previously served as President of Plains Midstream

Canada from 2020 until 2024, as President of PAA Natural Gas Storage from 2008 until 2020 and as President of Plains Gas Solutions from

2016 until 2020. Prior to joining Plains in 2008, Mr. Liollio held a number of executive roles including serving as President, Chief Executive

Officer and Director of EnergySouth, Inc. and as President and Chief Operating Officer of Centerpoint's natural gas distribution operations

across a five-state area including Houston. Mr. Liollio holds a Bachelor of Science degree in Industrial Engineering from Texas A&M University.

“We congratulate Dean on his promotion to the EVP and COO role.

Dean is immensely qualified to take on this key leadership role as he has been a member of our executive committee and has been instrumental

in executing on our recent initiatives,” said Willie Chiang, Chairman, CEO and President. “I would also like to thank Chris

for his many contributions to Plains and wish him the best in his future endeavors.”

About Plains

PAA is a publicly traded master limited partnership that owns and operates

midstream energy infrastructure and provides logistics services for crude oil. PAA owns an extensive network of pipeline gathering and

transportation systems, in addition to terminaling, storage, and other infrastructure assets serving key producing basins, transportation

corridors and major market hubs and export outlets in the United States and Canada.

PAGP is a publicly traded entity that owns an indirect, non-economic

controlling general partner interest in PAA and an indirect limited partner interest in PAA, one of the largest energy infrastructure

and logistics companies in North America.

PAA and PAGP are headquartered in Houston, Texas. More information

is available at www.plains.com.

Investor Relations Contacts:

Blake Fernandez

Ross Hovde

PlainsIR@plains.com

(866) 809-1291

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