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Exhibit 10.12.4

AMENDMENT NO. 4
TO AMENDED AND RESTATED
LIMITED LIABILITY COMPANY AGREEMENT
OF HCPI/TENNESSEE, LLC

        THIS AMENDMENT NO. 4 TO AMENDED AND RESTATED LIMITED LIABILITY COMPANY
AGREEMENT OF HCPI/TENNESSEE, LLC (this "Amendment") is effective as of the first
day date of January, 2007 (the "Effective Date") by HCP, Inc., a Maryland
corporation (f/k/a Health Care Property Investors, Inc.) (the "Managing
Member").

RECITALS

        A.    The Managing Member and each of the persons whose names are set
forth on Exhibit A thereto entered into the Amended and Restated Limited
Liability Company Agreement of HCPI/Tennessee, LLC effective as of October 2,
2003 (the "Original Agreement"), as amended by that certain Amendment No. 1 to
Amended and Restated Limited Liability Company Agreement of HCPI/Tennessee, LLC
dated September 29, 2004 (the "First Amendment"), that certain Amendment No. 2
to Amended and Restated Limited Liability Company Agreement of
HCPI/Tennessee, LLC dated October 27, 2004 (the "Second Amendment") and that
certain Amendment No. 3 to Amended and Restated Limited Liability Company
Agreement of HCPI/Tennessee, LLC and New Member Joinder Agreement dated
October 19, 2005 (the "Third Amendment," and together with the Original
Agreement, the First Amendment and the Second Amendment, the "Operating
Agreement"), and which provides that the Managing Member is the Managing Member
of Company. Capitalized terms used in this Amendment and not otherwise defined
in this Amendment shall have the meanings given to such terms in the Operating
Agreement.

        C.    The Managing Member has received the written consent of each
Member approving this Amendment.

AGREEMENT

        NOW, THEREFORE, the Operating Agreement is hereby amended as of the
Effective Date as follows:

        1.     The following definitions are added to Article 1 of the Operating
Agreement:

        "Contribution Amount" means, with respect to each Member, the weighted
average value per LLC Unit used for purposes of determining the number of LLC
Units to be issued to such Member from time to time as a result of its Capital
Contributions to the Company.

        "Cumulative Distributions" means, with respect to each Member or its
Assignees, the cumulative distributions received by such Member or its Assignees
pursuant to Sections 5.1.A(1), 5.1.A(2), 5.1.B, 5.6.A(1), 5.6.A(2), 5.6.B(1) and
5.6.B(2) for the current and all prior Fiscal Years.

        "Excess Distributions" means, with respect to each Member or its
Assignees, the excess of (i) such Member's Cumulative Distributions, over
(ii) the cumulative Net Income allocated to such Member or its Assignees
pursuant to Sections 6.2.A(2)(b) and 6.2.A(2)(c) and pursuant to former
Sections 6.2.A(2) and 6.2.B(2) of the Operating Agreement, in each case, for the
current and all prior Fiscal Years.

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        2.     Section 6.2 of the Operating Agreement is hereby deleted in its
entirely and replaced with the following:

Section 6.2    General Allocations

        A.    Net Income, Depreciation, and Net Loss.    Except as otherwise
provided in Sections 6.2.B or 6.3:

        (1)   Net Loss with respect to any Fiscal year of the Company shall be
allocated to the Members and Assignees in proportion to their Percentage
Interests.

        (2)   Net Income with respect to any Fiscal Year of the Company shall be
allocated as follows:

        (a)   First, to the Managing Member and the Non-Managing Members or
their Assignees in proportion to, and to the extent that, the amount of
cumulative Net Loss previously allocated to such Members or Assignees pursuant
to Section 6.2.A(1) exceeds the cumulative amount of Net Income previously
allocated to such Members or Assigness pursuant to this Section 6.2.A(2)(a);

        (b)   Second, to the Managing Member and the Non-Managing Members or
their Assignees in proportion to, and to the extent of, their Excess
Distributions;

        (c)   Thereafter, one hundred percent (100%) to the Managing Member or
its Assignees.

        (d)   To the extent the Net Income for a Fiscal Year is comprised of
items which are not all of the same character (e.g., ordinary income versus
capital gains), the Managing Member shall, subject to the foregoing provisions
of this Section 6.2.A(2), allocate such items to the Members in such manner,
taking into account the nature of the distributions previously made, and the
character of Net Income and Net Loss previously allocated, as determined in the
Managing Member's sole and absolute discretion.

        B.    Distributions Upon Liquidation.    If a Liquidating Event occurs
in any Fiscal Year, Net Income or Net Loss (or, if necessary, separate items of
income, gain, loss and deduction) for such Fiscal Year and any Fiscal Years
thereafter shall be allocated among the Members or their Assignees in such
amounts as will cause, to the greatest extent possible, the distributions to the
Members or their Assignees pursuant to Section 13.3.A(3) to be made in the
following order: (x) first, to the Non-Managing Members or their Assignees in
proportion to, and to the extent of, the number of LLC Units owned by each such
Member or its Assignees at the time of such payment multiplied by such Member's
Contribution Amount; (y) second, to the Managing Member or its Assignees in an
amount equal to the number of LLC Units owned by the Managing Member or its
Assignees at the time of such payment multiplied by the Managing Member's
Contribution Amount; and (z) third, ninety-nine percent (99%) to the Managing
Member or its Assignees and (y) one percent (1%) to the Non-Managing Members or
their Assignees in proportion to the number of Non-Managing Member Units held by
each such Non-Managing Member or its Assignees.

        3.     Sections 13.1.D and 13.1.E of the Operating Agreement are deleted
in their entirely and replaced with the following:

        D.    a final and non-appealable judgment is entered by a court of
competent jurisdiction ruling that the Managing Member is bankrupt or insolvent,
or a final and non-appealable order for relief is entered by a court with
appropriate jurisdiction against the Managing Member, in each case under any
Bankruptcy Law as now or hereafter in effect, unless prior to or within 90 days
after the entry of such order or judgment a Majority in Interest of the
Non-Managing Members Consent in writing to continue the business of the Company
and to the appointment, effective as of a date prior to the date of such order
or judgment, a substitute Managing Member;

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        E.    the Incapacity of the Managing Member that continues following the
Managing Member's good faith, commercially reasonable efforts to remedy such
Incapacity, unless prior to or within 90 days after such Incapacity a Majority
in Interest of the Non-Managing Members agree in writing to continue the
business of the Company and to the appointment, effective as of a date prior to
the date of such Incapacity, of a substitute Managing Member; or

        F.     a Terminating Capital Transaction.

        4.     Except as expressly amended hereby, the Operating Agreement
remains in full force and effect in accordance with its terms.

[signature page follows]

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        IN WITNESS WHEREOF, the undersigned has executed this Amendment
effective as of the date first written above.

MANAGING MEMBER:   HCP, Inc.,
a Maryland corporation
 
 
By:
/s/  EDWARD J. HENNING      

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    Name: Edward J. Henning
Title: Executive Vice President and General Counsel

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Exhibit 10.12.4

AMENDMENT NO. 4 TO AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT OF
HCPI/TENNESSEE, LLC
RECITALS
AGREEMENT