AR PAGP Partnership Agreement

At the Closing, PAGP GP entered into a Second Amended and
Restated Agreement of Limited Partnership of PAGP (the
AR PAGP
Partnership Agreement). The modifications
contained in the AR PAGP Partnership Agreement included the
following:

the establishment of the ClassC shares, a new class of
non-economic limited partner interests that will provide PAA,
as the sole holder, the right to vote in elections of eligible
PAGP GP directors together with the holders of PAGPs ClassA and
ClassB shares, which right will be exercised by PAA in
proportion to the votes of PAAs public common unit holders at
the annual meeting of PAAs limited partners commencing in 2018;

the revision of the definition of Outstanding with respect to
certain holders or groups of holders that beneficially own more
than 20% of an outstanding class of PAGPs equity interests so
that (i)such holder or group of holders will not be subject to
the 20% limitation contained in the definition of Outstanding
for purposes of nominating persons as eligible PAGPGP
directors; and (ii)not more than 19.9% of the outstanding
ClassA shares, ClassB shares and ClassC shares, taken together
as a single class, that are owned by such holder or group of
holders will be counted for purposes of determining a quorum
and voting in the election of eligible PAGPGP directors;

the addition of a requirement for the consent of the holders of
a majority of the outstanding ClassC Shares, voting as a single
class, with respect to certain amendments to the AR PAGP
Partnership Agreement that would have a material adverse effect
on the rights or preferences of the ClassC shareholders; and

the modification of the provisions relating to the right of
record holders of at least 10% of the outstanding ClassA shares
and ClassB shares to nominate a person to serve as an eligible
PAGPGP director by instead providing that such nomination
rights extend to record holders of at least 10% of the
outstanding ClassA, ClassB and ClassC shares, and the
authorization of PAA to nominate eligible PAGPGP directors on
behalf of its unitholders.

ARGPLLC Agreement

At the Closing, PAGP entered into a Seventh Amended and
Restated Limited Liability Company Agreement of GPLLC (the
ARGPLLC
Agreement). The modifications contained in the AR
GP LLC Agreement included the following:

the granting of authority to PAGP to manage the business and
affairs ofGPLLC, as its sole member;

the elimination of the board of directors of GP LLC; and

the granting to PAGP of the authority, in its sole discretion,
to establish a conflicts committee ofGPLLC for, among other
reasons, considering any conflict matters between PAGP and PAA,
including any matter with respect to which PAGP seeks to obtain
Special Approval (as defined in the AR PAA Partnership
Agreement (as defined below)).

AR AAP Partnership Agreement

At the Closing, GP LLC entered into an Eighth Amended and
Restated Agreement of Limited Partnership of AAP (the
AR AAP
Partnership Agreement). The modifications
contained in the AR AAP Partnership Agreement included the
following:

subject to certain limitations during the first twelve months
following the Closing as described below, the provision of a
right (a Redemption
Right) to each holder of AAP Units (other than
PAGP and GP LLC) to cause AAP to redeem any or all of such
holders AAP Units in exchange for the distribution of an
equivalent number of PAA Common Units held by AAP
(AAP Unit
Redemption). In connection with

any AAP Unit Redemption, the redeeming holder will transfer the
applicable AAP Units to AAP and a corresponding number of
ClassB shares and PAGPGP Units (if any), in each case, to PAGP.
The AAP Units transferred to AAP will be cancelled, the ClassB
shares transferred to PAGP will be cancelled and the PAGPGP
Units transferred to PAGP will remain outstanding and increase
PAGPs ownership percentage in PAGPGP; and

the contribution, distribution and tax allocation provisions in
the AR AAP Partnership Agreement were modified to accommodate
the Redemption Rights and to account for the fact that the
general partner interest in PAA will no longer be an economic
interest and the fact that following Closing, AAP will cease to
have any indebtedness for borrowed money.

The AR AAP Partnership Agreement generally restricts, subject
to certain exceptions, each holder of AAP Units (other than
PAGP andGPLLC, which have not been granted Redemption Rights)
from exercising its Redemption Rights with respect to
approximately 22% of its AAP Units for a period of twelve
months following the Closing. Greg Armstrong and Harry Pefanis,
our general partners Chief Executive Officer and Chief
Operating Officer, respectively, are restricted from directly
or indirectly (through PAA Management,L.P.) exercising their
respective Redemption Rights with respect to 50% of their AAP
Units during the same period. These restrictions are designed
to reduce, but not eliminate, the risk that any redemptions
during the first 12months following Closing, combined with
public trading of PAA Common Units, will cause a technical tax
termination of PAA. The holders of AAP Units (other than PAGP
andGPLLC) will continue to be permitted to exchange units for
ClassA shares without restriction.

AR PAA Partnership Agreement

At the Closing, PAA GP entered into a Sixth Amended and
Restated Agreement of Limited Partnership of PAA (the
AR PAA
Partnership Agreement). The modifications
contained in the AR PAA Partnership Agreement included the
following:

language reflecting and giving effect to theGP Conversion and
the IDR Redemption (as each term is defined below under Item
2.01) and related amendments;

the adjustment of certain tax allocation provisions to ensure
to the maximum extent possible the fungibility of (i)the PAA
Common Units issued in the PAA Recapitalization (as such term
is defined below under Item 2.01) and (ii)the other outstanding
PAA Common Units;

the revision of certain definitions to reflect the unified
governance structure contemplated by the Simplification
Transactions, including the definitions of Board of Directors
and Conflicts Committee;

the implementation of the rights of PAAs limited partners
(other than AAP) to direct PAA to vote its ClassC shares for
the election of eligible PAGPGP directors in the same
proportion as PAAs securities are voted at the annual meeting
of PAAs limited partners commencing in 2018;

the provision of the right to a holder of a limited partner
interest in PAA (other than AAP) that is equal to or greater
than 10% of the ClassA shares, ClassB shares and ClassC shares,
collectively, to direct PAA to nominate one person for election
as an eligible PAGPGP director;

the revision of the definition of Outstanding with respect to
any holder or group of holders that beneficially own more than
20% of an outstanding class of PAAs equity interests so that
(i)such holder or group of holders will not be subject to the
20% limitation contained in the definition of Outstanding for
purposes of nominating persons as eligible PAGPGP directors;
and(ii) not more than 19.9% of the outstanding ClassA shares,
ClassB shares and ClassC shares, taken together as a single
class, that are owned by such holder or group of holders, will
be counted for purposes of determining a quorum and voting in
the election of eligible PAGPGP directors; and

the elimination of any preemptive right of PAAGP or its
affiliates with respect to future issuances of partnership
securities by PAA.

Omnibus Agreement

At the Closing, the Plains Entities entered into the Omnibus
Agreement, which provides for, among other things, the
following:

that, for periods following the Closing, all direct or indirect
expenses of any of the Plains Entities will be paid by PAA,
other than income taxes, if any, of PAGP GP, PAGP, GP LLC, AAP
and PAA GP. Such direct or indirect expenses include, but are
not limited to (i)compensation for the directors of PAGPGP,
(ii)director and officer liability insurance, (iii)listing
exchange fees, (iv)investor relations expenses, and (v)fees
related to legal, tax, financial advisory and accounting
services;

the mechanics by which the number of ClassC shares outstanding
will equal, at all times, the number of PAAs units that are
outstanding and entitled to vote, other than such voting units
held by AAP;

the mechanics by which (i)the total number of PAGPs outstanding
ClassA shares will equal the number of AAP Units held by PAGP,
and (ii)the total number of PAA Common Units held by AAP will
equal the sum of the number of outstanding AAP Units and the
number of AAP Units that are issuable to the holders of AAP
Vested Units and AAP Earned Units (as those terms are defined
in the AR AAP Partnership Agreement);

the ability of PAGP to issue additional ClassA shares and use
the net proceeds therefrom to purchase a like number of AAP
Units from AAP, and the corresponding ability of AAP to use the
net proceeds therefrom to purchase a like number of PAA Common
Units from PAA; and

the ability of PAGP to lend proceeds of any future indebtedness
incurred by it to AAP, and AAPs corresponding ability to lend
such proceeds to PAA, in each case on substantially the same
terms as incurred by PAGP (also clarifying that PAA will
reimburse the net fees and expenses in connection with the
incurrence of such debt; provided that PAA will only be
required to reimburse such net fees and expenses on one
occasion with respect to each incurrence of indebtedness by PAA
from AAP).

AR Administrative Agreement

At the Closing, the Plains Entities amended and restated the
existing Administrative Agreement (as amended and restated, the
AR
Administrative Agreement) to remove the expense
allocation provisions among the Plains Entities, which
provisions are provided for in the Omnibus Agreement.

AAP Credit Agreement Amendment

At the Closing, to the Consent, Limited Waiver and Amendment,
dated as of August11, 2016 (the AAP Credit Agreement
Amendment), amending the Second Amended and
Restated Credit Agreement dated as of September26, 2013 among
AAP, Citibank, N.A. and the lenders party thereto (the
AAP Credit
Agreement), PAA assumed all remaining outstanding
indebtedness, obligations and liabilities of AAP under the AAP
Credit Agreement. Immediately prior to the Closing, AAP had
$550 million of term loan borrowings and $92 million of
revolving credit facility borrowings outstanding under the AAP
Credit Agreement.

On November15, 2016, PAA repaid the AAP Credit Agreement in
full and terminated the AAP Credit Agreement.

Registration Rights Agreement

At the Closing, the holders of AAP Units other than PAGP
andGPLLC (the Holders) entered into a Registration Rights
Agreement with PAA, to which PAA agreed to use commercially
reasonable efforts to

file, and cause to be continuously effective, a shelf
registration statement to permit the public resale of the PAA
Common Units held by AAP immediately following the Closing that
are distributable to the Holders to an AAP Unit Redemption.
Additionally, PAA agreed to register the resale of any PAA
Common Units issued to AAP following the Closing to the Omnibus
Agreement in respect of certain of AAPs ClassB units. In
certain circumstances, the holders will have piggyback
registration rights on offerings initiated by persons (other
than PAA) for whom PAA has the obligation to undertake an
underwritten offering (including the holders of its SeriesA
Preferred Units), and certain holders will collectively have
the right to request up to a total of twelve underwritten
offerings, subject to size limitations and customary rights of
PAA to delay such offerings.

The foregoing descriptions of the AR PAGP GP LLC Agreement, AR
PAGP Partnership Agreement, AR GP LLC Agreement, AR AAP
Partnership Agreement, AR PAA Partnership Agreement, Omnibus
Agreement, AR Administrative Agreement, AAP Credit Agreement
Amendment and Registration Rights Agreement are qualified in
their entirety by reference to the text of such agreements,
which are attached hereto as Exhibits 3.1, 3.2, 3.3, 3.4, 3.5,
10.1, 10.2, 10.3 and 10.4, respectively, and incorporated
herein by reference.

Item 1.02 Termination of Material
Definitive Agreement

The information included in Item 1.01 under the caption AAP
Credit Agreement Amendment is incorporated herein by reference.

Item 2.01 Completion of Acquisition or
Disposition of Assets

At the Closing, PAA GPs 2% general partner interest in PAA
converted into a non-economic general partner interest in PAA
(the GP
Conversion) and PAA redeemed and cancelled all of
the incentive distribution rights in PAA held by AAP (the
IDR
Redemption). As consideration for the GP
Conversion and IDR Redemption, PAA (i)issued, or to the Omnibus
Agreement agreed to issue, to AAP 245,500,000 PAA Common Units
and (ii)assumed AAPs remaining outstanding indebtedness,
obligations and liabilities under the AAP Credit Agreement as
described above in Item 1.01 under the caption AAP Credit
Agreement Amendment. These transactions are referred to herein
as the PAA
Recapitalization.

Item 2.03 Creation of a Direct
Financial Obligation or an Obligation under an Off-Balance
Sheet Arrangement of a Registrant

The information included in Item 1.01 under the caption AAP
Credit Agreement Amendment is incorporated herein by reference.

Item 3.02 Unregistered Sales of Equity
Securities

to the PAA Recapitalization, PAA issued 244,707,926 PAA Common
Units to AAP at the Closing. The information included in Item
2.01 is incorporated herein by reference. The PAA Common Units
were issued to AAP to an exemption under Section4(a)(2)of the
Securities Act of 1933.

Item 3.03 Material Modifications to
Rights of Security Holders

The information included in Item 1.01 under the captions AR
PAGP GP LLC Agreement, AR PAGP Partnership Agreement, AR GP LLC
Agreement, AR AAP Partnership Agreement, and AR PAA Partnership
Agreement is incorporated herein by reference.

Prior to the Closing, PAGPs shareholders did not have the
ability to elect members of the PAGP GP board until the overall
direct and indirect economic interest of certain of the legacy
owners of PAGP GP and their permitted transferees in AAP fell
below 40%, subject to certain time and other limitations (the
trigger
date). to the AR PAGP GP LLC Agreement, the
trigger date was accelerated to the Closing, and, as a result,
PAGP will hold an annual meeting for the election of eligible
PAGP GP directors beginning in 2018. The presence in person or
by proxy of the holders of a majority of PAGPs outstanding
ClassA, ClassB and ClassC shares, voting together as a single
class, will constitute a quorum. The eligible PAGP GP directors
will be elected by a plurality of the votes cast.

PAA will hold an annual meeting of its limited partners in
advance of PAGPs annual meeting of its limited partners. The
purpose of PAAs annual meeting will be to allow its limited
partners other than AAP to cast a pass-through vote instructing
PAA how to vote its ClassC Shares in such election. PAA will
vote (or refrain from voting) its ClassC shares for the
election of eligible PAGPGP directors in the same proportion as
the votes received from or withheld by its limited partners. At
the PAA annual meeting, PAA Common Units held by AAP will not
be voted and will not be counted for purposes of determining
whether a quorum exists.

Item 5.02 Departure of Directors or
Certain Officers; Election of Directors; Appointment of Certain
Officers; Compensatory Arrangements of Certain
Officers

Prior to the Closing, PAGP GP managed the business and affairs
of PAGP, and GP LLC managed the business and affairs of PAA and
AAP. to the AR GP LLC Agreement, PAGP, as the sole member of GP
LLC, has the sole authority to manage the business and affairs
of GP LLC, and the current board of directors of GP LLC (the GP
LLC board) was eliminated. As a result, the PAGP GP board will
have responsibility for managing the business and affairs of
each of PAGP, AAP and PAA. At the Closing, Messrs.Christopher
M. Temple, Gary R. Petersen and J. Taft Symonds, who were the
directors of the GP LLC board that were not also directors of
the PAGP GP board, were added to the PAGP GP board. Victor Burk
and Bobby S. Shackouls, who were not members of the GP LLC
board, are current members of the PAGP GP board.

The following table sets forth certain information with respect
to the persons that serve as directors of PAGP GP.

For more information regarding the directors of the PAGP GP
board, please see PAGPs and PAAs respective Annual Reports on
Form10-K for the year ended December31, 2015, each of which
were filed on February25, 2016, as well as PAGPs definitive
proxy statement filed on October7, 2016.

Item 5.03 Amendments to Articles of
Incorporation or Bylaws; Change in Fiscal Year

The information included in Item 1.01 under the captions AR
PAGP GP LLC Agreement, AR PAGP Partnership Agreement, AR GP LLC
Agreement, AR AAP Partnership Agreement, and AR PAA Partnership
Agreement is incorporated herein by reference.

Item 9.01 Financial Statements and
Exhibits

(d) Exhibits.