Amendment dated March 22, 2018 to PAA LTIP Grant Letter dated August 24, 2015 (Willie Chiang)

WCW (Willie) Chiang

[Address]

Dear Willie:

I am pleased to inform you that you have been granted 120,000 Phantom Units as of the above date pursuant to the Company’s PNG Successor Long-Term Incentive Plan (the "Plan"). In addition, in tandem with each Phantom Unit, you have been granted a distribution equivalent right (a “DER”). A DER represents the right to receive a cash payment equivalent to the amount, if any, paid in cash distributions on one Common Unit of Plains All American Pipeline, L.P. (“PAA” or the “Partnership”) to the holder of such Common Unit. The terms and conditions of this grant are as set forth below.

As used herein, (i) the “Company” refers to Plains All American GP LLC; (ii) “Distribution Date” means the day in February, May, August or November in any year (as context dictates) that is 45 days after the end of the most recently completed calendar quarter (or, if not a business day, the closest

previous business day); and (iii) “Market Value” means the average of the closing sales prices for a Common Unit on the New York Stock Exchange for the five trading days preceding the then most recent “ex dividend” date for payment of a distribution by the Partnership.

The phrase “Change in Status” means (A) the termination of your employment by the Company other than a Termination for Cause, within two and a half months prior to or one year following a Change of Control (the “Protected Period”), or (B) the termination of your employment by you due to the occurrence during the Protected Period, without your written consent, of (i) any material diminution in your authority, duties or responsibilities (taking into account additional authority, responsibilities or duties associated with the initial transition of responsibilities to you, the overall growth of the Partnership or a promotion or lateral transfer accepted by you), or (ii) any other action or inaction that constitutes a material breach of this Agreement by the Company. A termination by you shall not be a Change in Status unless (1) you provide written notice to the Company of the condition in (B)(i) or (ii) that would constitute a Change in Status within 90 days of the initial existence of the condition, (2) the Company fails to remedy the condition within the 30-day period following such notice and (3) you terminate your employment within 10 days following the end of such 30-day period.

The phrase “Change of Control” means, and shall be deemed to have occurred upon the occurrence of, one or more of the following events: (i) Plains GP Holdings, L.P. (“PAGP”) ceases to retain direct or indirect control of the general partner of the Partnership; (ii) PAGP ceases to beneficially own, directly or indirectly, more than 50% of the membership interest in the Company; (iii) any direct or indirect sale, lease, exchange or other transfer (in one transaction or a series of related transactions and whether by merger or otherwise) of all or substantially all of the assets of the Partnership, PAGP or the Company to one or more Persons who are not affiliates of PAGP (“third party or parties”), other than a transaction in which the Owner Affiliates (as defined below) continue to beneficially own, directly or indirectly, more than 50% of the issued and outstanding voting securities of such third party or parties immediately following such transaction; (iv) (x) a “person” or “group” (as such terms are defined in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) other than the Owner Affiliates becomes the “beneficial owner” directly or indirectly of 25% or more of the member interest in PAA GP Holdings LLC, a Delaware limited liability company and the general partner of PAGP (“PAGP GP”), and (y) the member interest beneficially owned by such "person" or "group" exceeds the aggregate member interest in PAGP GP beneficially owned, directly or indirectly, by the Owner Affiliates; (v) any Person (other than PAGP or its wholly owned subsidiaries), including any partnership, limited partnership, syndicate or other “person” or “group,” becomes the beneficial owner, directly or indirectly, of 50% or more of the membership interest in the Company or 50% or more of the outstanding limited partnership interests of PAGP; or (vi) any Person (other than PAGP or its wholly owned subsidiaries), including any partnership, limited partnership, syndicate or other “person” or “group,” becomes the beneficial owner, directly or indirectly, of 50% or more of the membership interest in PAGP GP.

As used herein, the term “Owner Affiliates” shall mean KAFU Holdings, L.P. and its affiliates, EMG Investment, LLC and its affiliates, Oxy Holding Company (Pipeline), Inc. and its affiliates, Mark Strome and his affiliates, Windy, LLC and its affiliates, PAA Management, L.P. and its affiliates, PAGP and its affiliates, Jay Chernosky, Kipp PAA Trust, Paul Riddle, Russell Clingman, David Humphreys and Philip Trinder.

The phrase “Termination for Cause” shall mean severance of your employment with the Company or its Affiliates based on your (i) substantial failure to perform the duties and responsibilities of your position at an acceptable level as reasonably determined in good faith by the CEO and President-COO of the Company (or if you are the CEO of the Company, by vote of the Board of Directors of the Company excluding you if you are a member thereof) and after written notice specifying such failure in detail and after a reasonable period under the circumstances (determined by the CEO of the Company, or alternatively the Board of Directors, in good faith) such failure has continued without full correction by you, (ii) conviction of or guilty plea to the committing of an act or acts constituting a felony under the laws of the United States or any state thereof or any misdemeanor involving moral turpitude, or (iii) violation of the Company’s Code of Business Conduct (unless waived in accordance with the terms thereof), in each case with the specific failure or violation described to you in writing.

Terms used herein that are not defined herein shall have the meanings set forth in the Plan or, if not defined in the Plan, in the Fourth Amended and Restated Agreement of Limited Partnership of Plains All American Pipeline, L.P., as amended (the "Partnership Agreement").

This award is intended to either (i) qualify as a “short-term deferral” under Section 409A of the Internal Revenue Code of 1986, as amended, or (ii) comply with the provisions of Section 409A. If it is determined that any payments or benefits to be made or provided under this Agreement do not comply with Section 409A, the parties agree to amend this Agreement or take such other actions as reasonably necessary or appropriate to comply with Section 409A while preserving the economic agreement of the parties.

By signing below, you agree that the Phantom Units and DERs granted hereunder are governed by the terms of the Plan. Copies of the Plan and the Partnership Agreement are available upon request. In the event any provisions of this award conflict with provisions in the Employment Letter, the Employment Letter shall control.

In order for this grant to be effective you must designate a beneficiary that will be entitled to receive any benefits payable under this grant in the event of your death. Unless you indicate otherwise by checking the appropriate box the named beneficiaries on this form will serve as your beneficiaries for all previous LTIP grants.

Please execute and return a copy of this grant letter to me and retain a copy for your records.

PLAINS ALL AMERICAN PIPELINE, L.P.

By: PAA GP LLC

By: PLAINS AAP, L.P.

By: PLAINS ALL AMERICAN GP LLC

□ Check this box only if designation does not apply to prior grants

_____________________________

Units:     120,000            

Dated: ________________________