Description of Our Securities

As of December 31, 2022, Plains All American Pipeline L.P. has one class of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): its common units representing limited partner interests, which are described in this Exhibit. The following definitions are used in this Exhibit:

•"Partnership," "Plains," "PAA," "we," "us," "our," "ours" and similar terms refer to Plains All American Pipeline, L.P. and its subsidiaries; and

•"General partner," refers to, as the context requires, any or all of PAA GP Holdings LLC ("PAGP GP"), Plains GP Holdings, L.P. ("PAGP"), Plains AAP, L.P. ("AAP") and Plains All American GP LLC ("GP LLC").

Generally, our common units represent limited partner interests that entitle the holders to participate in our cash distributions and to exercise the rights and privileges available to limited partners under our partnership agreement. For a description of the relative rights and preferences of holders of common units in and to cash distributions, see "Our Cash Distribution Policy."

Our outstanding common units are listed on the Nasdaq Global Select Market under the symbol "PAA." Any additional common units we issue will also be listed on Nasdaq.

Each holder of common units is entitled to one vote for each common unit on all matters submitted to a vote of the common unitholders. However, our unitholders are limited partners and do not directly or indirectly participate in our management or operation. Unlike holders of common stock in a corporation, our unitholders have only limited voting rights on matters affecting our business or governance, including the director voting rights described below.

Our general partner manages our day-to-day operations and activities; however, PAGP effectively controls our business and affairs through the exercise of its rights as the sole and managing member of GP LLC. The business and affairs of GP LLC are managed by or under the direction of the board of directors of PAGP GP, which we refer to as our "board of directors" or "board."

Subject to limited exceptions, PAGP GP’s Fourth Amended and Restated Limited Liability Company Agreement (as amended, the “PAGP GP LLC Agreement”) provides that the Board will consist of up to 13 members, including the CEO. In addition, if PAA fails to make three distributions on its Series A preferred units (whether or not consecutive), the holders of Series A preferred units will have the right to appoint a new member of the Board to serve until such time as all accrued and unpaid distributions on the Series A preferred units have been paid in full.

The Board is divided into three staggered classes. At each annual meeting, only the directors of the class whose term is expiring will be up for election and, upon election, the elected directors in that class will serve for a term of three years, subject to a director's earlier resignation, death or removal. If a director is elected to the board to fill a vacancy, that director will have the same remaining term as his or her predecessor.

PAGP holds annual shareholder meetings for the purpose of electing directors. PAA, which holds all of PAGP's issued and outstanding Class C shares, will hold annual meetings of its limited partners entitled to vote immediately in advance of PAGP's annual meetings. The purpose of our annual meetings is to allow our limited partners, other than AAP and holders of our Series B preferred units, to cast a "pass-through" vote instructing us how to vote the Class C shares that we own in the election of directors at PAGP’s annual meeting. We will vote (or refrain from voting) our Class C shares for the election of directors at the direction and on behalf of our eligible common and Series A preferred unitholders in the same proportion as the votes received from or withheld by our limited partners. Common units held by AAP will not be voted in the election of directors and will not be counted for purposes of determining whether a quorum exists.

Except as described under "Description of Our Partnership Agreement—Limited Liability," the common units will be fully paid, and common unitholders will not be required to make additional capital contributions to us.

Each purchaser of common units must execute a transfer application whereby the purchaser requests admission as a substituted limited partner and makes representations and agrees to provisions stated in the transfer application. If this action is not taken, a purchaser will not be registered as a record holder of common units on the books of our transfer agent or issued a common unit certificate. Purchasers may hold common units in nominee accounts.

An assignee, pending its admission as a substituted limited partner, is entitled to an interest in us equivalent to that of a limited partner with respect to the right to share in allocations and distributions, including liquidating distributions. Our general partner will vote and exercise other powers attributable to common units owned by an assignee who has not become a substituted limited partner at the written direction of the assignee. A nominee or broker who has executed a transfer application with respect to common units held in street name or nominee accounts will receive distributions and reports pertaining to its common units.

Each holder of AAP's Class A units (other than PAGP) has the right (a "Redemption Right") to cause AAP to redeem any or all of such holder's AAP Class A units in exchange for the distribution of an equivalent number of our common units held by AAP. In connection with any such redemption, the redeeming holder will transfer the AAP Class A units to AAP and a corresponding number of PAGP Class B shares and general partner units (if applicable), in each case, to PAGP. The AAP Class A units transferred to AAP will be canceled, the PAGP Class B shares transferred to PAGP will be canceled and the general partner units transferred to PAGP (if applicable) will remain outstanding and increase PAGP's ownership percentage in PAGP GP.

The above mechanisms are subject to customary conversion rate adjustments for equity splits, equity dividends and reclassifications.

General. We will distribute to our unitholders, on a quarterly basis, all of our available cash in the manner described below.

Definition of Available Cash. Available cash generally means, for any quarter ending prior to liquidation, all cash and cash equivalents on hand at the end of that quarter less reserves established in the reasonable discretion of the general partner to:

•provide for the proper conduct of our business and the business of our operating partnerships (including reserves for future capital expenditures and for our anticipated future credit needs);

•comply with applicable law or any loan agreement, security agreement, mortgage, debt instrument or other agreement or obligation; or

•provide funds for future distributions to our Series A and Series B preferred unitholders or distributions to our common unitholders for of any one or more of the next four quarters.

Our available cash also includes cash on hand resulting from borrowings made after the end of the quarter.

General. Cash distributions to our common unitholders will be characterized as either operating surplus or capital surplus. We distribute available cash from operating surplus differently than available cash from capital surplus. See "—Quarterly Distributions of Available Cash."

Definition of Operating Surplus. Operating surplus refers generally to:

•our cash balances on the closing date of our initial public offering; plus

•$25 million; plus

•all of our cash receipts from operations, excluding cash that is capital surplus; less

•all of our operating expenses, debt service payments (but not including payments required with the sale of assets or any refinancing with the proceeds of new indebtedness or an equity offering), maintenance capital expenditures and reserves established for future operations.

Definition of Capital Surplus. Capital surplus will generally be generated only by:

•borrowings other than working capital borrowings;

•sales of debt and equity securities; and

•sales or other dispositions of assets for cash, other than inventory, accounts receivable and other assets in the ordinary course of business.

We will treat all available cash distributed as coming from operating surplus until the sum of all available cash distributed after the closing date of our initial public offering equals the operating surplus as of the end of the quarter prior to the distribution. Any available cash in excess of operating surplus, regardless of its source, will be treated as capital surplus.

If we distribute available cash from capital surplus for each common unit in an aggregate amount per common unit equal to the initial public offering price of the common units, there will not be a distinction between operating surplus and capital surplus, and all distributions of available cash will be treated as operating surplus. We do not anticipate that we will make distributions from capital surplus.

We can issue additional common units or other equity securities for consideration and under terms and conditions approved by our general partner in its sole discretion and without the approval of our unitholders, other than current holders of our Series A preferred units and Series B preferred units in certain circumstances. We may fund acquisitions through the issuance of additional common units or other equity securities.

Holders of any additional common units that we issue will be entitled to share equally with our then-existing common unitholders in distributions of available cash. In addition, the issuance of additional interests may dilute the value of the interests of the then-existing unitholders.

After making distributions to holders of our outstanding preferred units, we will distribute the remainder of our available cash for each quarter prior to our liquidation to our common unitholders. We expect to make distributions of all available cash within 45 days after the end of each quarter to holders of record on the applicable record date.

We will make distributions of available cash from operating surplus to all common unitholders, pro rata until we distribute an aggregate amount of available cash equal to the aggregate operating surplus generated by the Partnership from the time of our initial public offering through the end of the quarter in respect of such distribution.

We will make distributions of available cash from capital surplus to all common unitholders pro rata. We may not make distributions of capital surplus without the approval of (i) holders of at least 75% of the outstanding Series A preferred units and (ii) holders of at least 662/3% of the outstanding Series B preferred units.

If we dissolve and liquidate, we will sell or otherwise dispose of our assets and adjust the partners' capital account balances to reflect any resulting gain or loss. We will apply the proceeds of liquidation (i) first to the payment of our creditors in the order of priority provided in our partnership agreement and by law, (ii) second to the holders of outstanding preferred units in accordance with their adjusted capital account balances and (iii) thereafter, to the common unitholders in accordance with their adjusted capital account balances.

The following is a summary of certain material provisions of our partnership agreement.

Our purpose under our partnership agreement is to serve as a partner of our operating partnerships and to engage in any business activities that may be engaged in by our operating partnerships or that are approved by our general partner. The partnership agreements of our operating partnerships provide that they may engage in any activity that was engaged in by our predecessors at the time of our initial public offering or reasonably related thereto and any other activity approved by our general partner.

Our partnership agreement is governed by Delaware law. Our partnership agreement requires that any claims, suits, actions or proceedings:

•arising out of or relating in any way to the partnership agreement (including any claims, suits or actions to interpret, apply or enforce the provisions of the partnership agreement or the duties, obligations or liabilities among unitholders or of unitholders to us, or the rights or powers of, or restrictions on, the unitholders or us);

•brought in a derivative manner on our behalf;

•asserting a claim arising pursuant to any provision of the Delaware Revised Uniform Limited Partnership Act (the “Delaware Act”); or

shall be exclusively brought in the Court of Chancery of the State of Delaware (or, if such court does not have subject matter jurisdiction thereof, any other court located in the State of Delaware with subject matter jurisdiction), regardless of whether such claims, suits, actions or proceedings sound in contract, tort, fraud or otherwise, are based on common law, statutory, equitable, legal or other grounds, or are derivative or direct claims. By purchasing a common unit, a unitholder is irrevocably consenting to these limitations and provisions regarding claims, suits, actions or proceedings and submitting to the exclusive jurisdiction of the Court of Chancery of the State of Delaware (or such other Delaware courts) in connection with any such claims, suits, actions or proceedings. The exclusive forum provision would not apply to suits brought to enforce any liability or duty created by the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. To the extent any such claims may be based upon federal law claims, Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. Furthermore, Section 22 of the Securities Act creates concurrent jurisdiction for the federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder.

Each limited partner, and each person who acquires a unit from a unitholder and executes and delivers a transfer application, grants to our general partner and, if appointed, a liquidator, a power of attorney to, among other things, execute and file documents required for our qualification, continuance or dissolution. The power of attorney also grants the authority for the amendment of, and to make consents and waivers under, our partnership agreement.

Our partnership agreement authorizes us to issue an unlimited number of additional limited partner interests and other equity securities that are equal in rank with or junior to our common units on terms and conditions established by our general partner in its sole discretion without the approval of any limited partners.

It is likely that we will fund acquisitions through the issuance of additional common units or other equity securities. Holders of any additional common units we issue will be entitled to share equally with the then-existing holders of common units in our cash distributions. In addition, the issuance of additional partnership interests may dilute the value of the interests of the then-existing holders of common units in our net assets.

In accordance with Delaware law and the provisions of our partnership agreement, we may also issue additional partnership interests that, in the sole discretion of our general partner, may have special voting rights to which common units are not entitled.

Our general partner has the right, which it may from time to time assign in whole or in part to any of its affiliates, to purchase common units or other equity securities whenever, and on the same terms that, we issue those securities to persons other than our general partner and its affiliates, to the extent necessary to maintain their percentage interests in us that existed immediately prior to the issuance. The holders of common units will not have preemptive rights to acquire additional common units or other partnership interests in us.

Amendments to our partnership agreement may be proposed only by our general partner. Any amendment that materially and adversely affects the rights or preferences of any type or class of limited partner interests in relation to other types or classes of limited partner interests or our general partner interest will require the approval of at least a majority of the type or class of limited partner interests or general partner interests so affected. However, in some circumstances, more particularly described in our partnership agreement, our general partner may make amendments to our partnership agreement without the approval of our limited partners or assignees.

Our general partner may withdraw as general partner without obtaining approval of any unitholder by giving 90 days' written notice, and that withdrawal will not constitute a violation of our partnership agreement. In addition, our general partner may withdraw without unitholder approval upon 90 days' notice to our limited partners if at least 50% of our outstanding units are held or controlled by one person and its affiliates other than our general partner and its affiliates.

Upon the voluntary withdrawal of our general partner, the holders of a majority of our outstanding common units and Series A preferred units, excluding any common units and Series A preferred units held by the withdrawing general partner and its affiliates, may elect a successor to the withdrawing general partner. If a successor is not elected, or is elected but an opinion of counsel regarding limited liability and tax matters cannot be obtained, we will be dissolved, wound up and liquidated, unless within 90 days after that withdrawal, the holders of a majority of our outstanding common units and Series A preferred units, excluding the common units and Series A preferred units held by the withdrawing general partner and its affiliates, agree to continue our business and to appoint a successor general partner.

Our general partner may not be removed unless that removal is approved by the vote of the holders of not less than two-thirds of our outstanding units, including units held by our general partner and its affiliates, and we receive an opinion of counsel regarding limited liability and tax matters. Any removal of this kind is also subject to the approval of a successor general partner by the vote of the holders of a majority of our outstanding common units and Series A preferred units, including those held by our general partner and its affiliates.

While our partnership agreement limits the ability of our general partner to withdraw, it allows the general partner interest to be transferred to an affiliate or to a third party in conjunction with a merger or sale of all or substantially all of the assets of our general partner.

In addition, our partnership agreement expressly permits the sale, in whole or in part, of the ownership of our general partner. Our general partner may also transfer, in whole or in part, the common units it owns.

A merger or consolidation of us requires the prior consent of our general partner. However, our partnership agreement generally prohibits our general partner, without the prior approval of a majority of our outstanding units, from causing us to, among other things, sell, exchange or otherwise dispose of all or substantially all of our assets in a single transaction or a series of related transactions. Our general partner may, however, mortgage, pledge, hypothecate or grant a security interest in all or substantially all of our assets without that approval. Our general partner may also sell all or substantially all of our assets under a foreclosure or other realization upon those encumbrances without that approval.

If conditions specified in our partnership agreement are satisfied, our general partner may merge us or any of our subsidiaries into, or convey some or all of our assets to, a newly formed entity if the sole purpose of that merger or conveyance is to effect a mere change in our legal form into another limited liability entity. Our unitholders are not entitled to dissenters’ rights or appraisal rights (and, therefore, will not be entitled to demand payment of a fair price for their units) under our partnership agreement or applicable Delaware law in the event of a merger or consolidation, a sale of substantially all of our assets or any other transaction or event.

Upon our dissolution, unless we are reconstituted and continued as a new limited partnership, the person authorized to wind up our affairs (the liquidator) will, acting with all the powers of our general partner that the liquidator deems necessary or desirable in its good faith judgment, liquidate our assets. The proceeds of the liquidation will be applied as follows:

•first, towards the payment of all of our creditors and the creation of a reserve for contingent liabilities;

•next, to all holders of preferred units an aggregate amount equal to the positive balance in their capital accounts distributed in a manner that provides the holders of preferred units with the same percentage of their respective liquidation preferences; and

•finally, to all partners in accordance with the positive balance in their respective capital accounts.

Under some circumstances and subject to some limitations, the liquidator may defer liquidation or distribution of our assets for a reasonable period of time. If the liquidator determines that a sale would be impractical or would cause a loss to our partners, our general partner may distribute assets in kind to our partners.

Our partnership agreement contains the following specific provisions that are intended to discourage a person or group from attempting to remove our general partner or otherwise change management:

•generally, if a person acquires 20% or more of any class of units then outstanding other than from our general partner or its affiliates, the units owned by such person cannot be voted on any matter; and

•provisions limiting the ability of unitholders to call meetings or to acquire information about our operations, as well as other provisions limiting the unitholders' ability to influence the manner or direction of management.

If at any time our general partner and its affiliates (other than, with respect to the Series A preferred units, such affiliates that originally purchased Series A preferred units) own 80% or more of the issued and outstanding limited partner interests of any class, our general partner will have the right to purchase all, but not less than all, of the outstanding limited partner interests of that class that are held by non-affiliated persons. The record date for determining ownership of the limited partner interests would be selected by our general partner on at least 10 but not more than 60 days' notice. The purchase price in the event of a purchase under these provisions would be the greater of (1) the current market price (as defined in our partnership agreement) of the limited partner interests of the class as of the date three days prior to the date that notice is mailed to the limited partners as provided in our partnership agreement and (2) the highest cash price paid by our general partner or any of its affiliates for any limited partner interest of the class purchased within the 90 days preceding the date our general partner mails notice of its election to purchase the units.

We are authorized to purchase insurance against liabilities asserted against and expenses incurred by persons for our activities, regardless of whether we would have the power to indemnify the person against liabilities under our partnership agreement.

Under our partnership agreement, we have agreed to register for resale under the Securities Act and applicable state securities laws any common units, or other partnership securities proposed to be sold by our general partner or any of its affiliates or their assignees if an exemption from the registration requirements is not otherwise available. We are obligated to pay all expenses incidental to the registration, excluding underwriting discounts and commissions.

Assuming that a limited partner does not participate in the control of our business within the meaning of the Delaware Act and that he otherwise acts in conformity with the provisions of our partnership agreement, his liability under the Delaware Act will be limited, subject to some possible exceptions, generally to the amount of capital he is obligated to contribute to us in respect of his units plus his share of any undistributed profits and assets.

Under the Delaware Act, a limited partnership may not make a distribution to a partner to the extent that at the time of the distribution, after giving effect to the distribution, all liabilities of the partnership, other than liabilities to partners on account of their partnership interests and liabilities for which the recourse of creditors is limited to specific property of the partnership, exceed the fair value of the assets of the limited partnership. For the purposes of determining the fair value of the assets of a limited partnership, the Delaware Act provides that the fair value of the property subject to liability of which recourse of creditors is limited shall be included in the assets of the limited partnership only to the extent that the fair value of that property exceeds the nonrecourse liability. The Delaware Act provides that a limited partner who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware Act is liable to the limited partnership for the amount of the distribution for three years from the date of the distribution.

In addition, our partnership agreement limits any fiduciary duties our general partner might owe to our unitholders. As our general partner, our general partner is liable for all of our debts (to the extent not paid from our assets), except for indebtedness or other obligations that are made specifically non-recourse to it. Our general partner has the sole discretion to incur indebtedness or other obligations on our behalf on a non-recourse basis to the general partner. Our general partner has in the past exercised such discretion, in most instances involving payment liability.