Second Amendment dated March 22, 2018 to Plains AAP, L.P. Class B Restricted Units Agreement (Willie Chiang)

This Second Amendment to Plains AAP, L.P. Class B Restricted Units Agreement (this “Amendment”) is entered into effective as of the 22nd day of March, 2018 by and between Plains AAP, L.P., a Delaware limited partnership (the “Partnership”) and the undersigned individual (“Executive”).

WHEREAS, the Partnership and Executive have previously entered into that certain Plains AAP, L.P. Class B Restricted Unit Agreement dated as of August 24, 2015 (such agreement being herein referred to as the “Class B Agreement”).

WHEREAS, the Partnership and Executive have previously entered into that certain First Amendment to the Class B Agreement dated as of August 25, 2016 (the “First Amendment”).

WHEREAS, Executive and the Partnership desire to enter into this Amendment for the purpose of evidencing certain mutually beneficial amendments to the Class B Agreement.

NOW, THEREFORE, in consideration of the mutual agreements set forth herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Partnership and Executive hereby agree that Section 2.2(b) of the Class B Agreement, as amended by the First Amendment, is hereby deleted and replaced in its entirety as follows:

(b) Earned Units. The Partnership and Executive acknowledge and agree that the Granted Units shall become Earned Units as follows:

For each of the above performance thresholds, the referenced DCF level will be subject to adjustment as determined by the Chief Executive Officer of the Company in his sole discretion to account for significant asset sales (and if at such time the Executive is the Chief Executive Officer of the Company, the determination as to whether there shall be any such adjustment shall be made by the Board in its sole discretion). Once a Granted Unit has become an Earned Unit pursuant to this Agreement, the Earned Unit shall remain an Earned Unit thereafter until it either becomes a Vested Unit or is purchased by the Partnership pursuant to the exercise of its Call Option.

Except as amended by this Amendment and the First Amendment, the Class B Agreement shall remain in full force and effect according to its terms. Any capitalized term used herein but not defined shall have the meaning given such term in the Class B Agreement.