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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;5. Medical Office Building Joint Ventures&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;NHP/PMB L.P.&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;In February&amp;#160;2008, we entered into an agreement (the &amp;#8220;Contribution Agreement&amp;#8221;) with Pacific
   Medical Buildings LLC and certain of its affiliates to acquire up to 18 multi-tenant medical office
   buildings, including six that were in development, for $747.6&amp;#160;million, including the assumption of
   approximately $282.6&amp;#160;million of mortgage financing. Under the Contribution Agreement, in 2008,
   NHP/PMB acquired interests in nine of the 18 medical office buildings, one of which consisted of a
   50% interest through a joint venture which is consolidated by NHP/PMB. During 2008, we also
   acquired one of the 18 medical office buildings directly (not through NHP/PMB). During 2009, we
   elected to terminate the Contribution Agreement with respect to six properties after the conditions
   for us to close on such properties were not satisfied. As a result of the elimination of these six
   properties, under the Contribution Agreement, NHP/PMB became obligated to pay $3.0&amp;#160;million, of
   which $2.7&amp;#160;million was payable to Pacific Medical Buildings LLC.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of February&amp;#160;1, 2010, we entered into an amendment to the Contribution Agreement which
   reinstated one of the six properties that were previously eliminated from the Contribution
   Agreement. NHP/PMB acquired this multi-tenant medical office building for $74.0&amp;#160;million, which was
   paid in a combination of cash and the issuance of 301,599 OP Units with a fair value at the date of
   issuance of $10.0&amp;#160;million. As a result of such acquisition, we retired our $47.5&amp;#160;million mortgage
   loan from a related party to which such acquired medical office building had served as collateral
   (see Note 18). Additionally, as of February&amp;#160;1, 2010, we acquired a majority ownership interest in a
   joint venture which owns one multi-tenant medical office building (see &lt;i&gt;NHP/PMB Gilbert LLC &lt;/i&gt;below),
   amended and restated our agreement with NHP/PMB, PMB LLC and PMB Real Estate Services LLC
   (&amp;#8220;PMBRES&amp;#8221;) as
   described below and amended our agreement with PMB Pomona LLC to provide for the future
   acquisition by NHP/PMB of a medical office building currently in development (see Note 18). In
   connection with these transactions, NHP/PMB entered into a Third Amendment to the Amended and
   Restated Agreement of Limited Partnership of NHP/PMB, which, among other things, authorized NHP/PMB
   to acquire properties affiliated with Pacific Medical Buildings LLC pursuant to agreements other
   than the Contribution Agreement.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of March&amp;#160;1, 2010, we entered into an amendment to the Contribution Agreement which
   reinstated another two of the six properties that were previously eliminated from the Contribution
   Agreement. NHP/PMB acquired a 65% interest in a joint venture which is consolidated by NHP/PMB that
   owns one of the two multi-tenant medical office buildings valued at $79.9&amp;#160;million. The acquisition
   was paid in a combination of cash, the assumption of $48.1&amp;#160;million of mortgage financing and the
   issuance of 152,238 OP Units with a fair value at the date of issuance of $5.0&amp;#160;million. NHP/PMB
   acquired a 69% interest in a joint venture which is consolidated by NHP/PMB that owns the second
   multi-tenant medical office building valued at $69.3&amp;#160;million. The acquisition was paid in a
   combination of cash, the assumption of $50.2&amp;#160;million of mortgage financing and the issuance of
   121,489 OP Units with a fair value at the date of issuance of $4.0&amp;#160;million. Additionally, as of
   March&amp;#160;1, 2010, we acquired the remaining interest in PMB SB (see Note 6).
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;The amendment to the Contribution Agreement dated as of March&amp;#160;1, 2010 also eliminated one of
   the two remaining properties from the Contribution Agreement, however, we concurrently entered into
   a joint venture with PMB Pasadena LLC (an entity affiliated with Pacific Medical Buildings LLC) to
   acquire this property (see &lt;i&gt;NHP/PMB Pasadena LLC &lt;/i&gt;below). As a result of the elimination of this
   property from the Contribution Agreement, NHP/PMB became obligated to pay $2.1&amp;#160;million (the
   &amp;#8220;Premium Adjustment&amp;#8221;), of which $1.9&amp;#160;million was payable to Pacific Medical Buildings LLC in cash.
   The portion of the Premium Adjustment not payable to Pacific Medical Buildings LLC was paid in the
   form of $0.1&amp;#160;million in cash and the issuance of 1,788 additional OP Units with an aggregate value
   of $57,000. As a result of the payment, we received an additional 4,514 Class&amp;#160;B limited partnership
   units in NHP/PMB. Under the Contribution Agreement, if the agreement is terminated with respect to
   the remaining development property, NHP/PMB will become obligated to pay approximately $2.4&amp;#160;million
   (the &amp;#8220;Future Premium Adjustment&amp;#8221;) which has been accrued at September&amp;#160;30, 2010 and of which a
   portion would be payable to Pacific Medical Buildings LLC.
   &lt;/div&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Under the terms of the Contribution Agreement, a portion of the consideration for the
   multi-tenant medical office buildings is paid in the form of OP Units. After a one-year holding
   period, the OP Units are exchangeable for cash or, at our option, shares of our common stock equal
   to the REIT Shares Amount. During the nine months ended September&amp;#160;30, 2010, 16,285 OP Units were
   converted into 16,285 shares of our common stock. As of September&amp;#160;30, 2010, 1,613,467 of the
   remaining OP Units had been outstanding for one year or longer and were exchangeable for cash of
   $62.4&amp;#160;million. During the nine months ended September&amp;#160;30, 2010, cash distributions from NHP/PMB of
   $2.6&amp;#160;million were made to OP unitholders.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Additionally, we have entered into an agreement (the &amp;#8220;Pipeline Agreement&amp;#8221;) with NHP/PMB, PMB
   LLC and PMBRES (see Note 6) pursuant to which we or NHP/PMB currently have the right, but not the
   obligation, to acquire up to approximately $1.3&amp;#160;billion of multi-tenant medical office buildings
   developed by PMB LLC through April&amp;#160;2019. As of February&amp;#160;1, 2010, the Pipeline Agreement was amended
   and restated to provide NHP/PMB with the option to acquire medical office buildings developed in
   the future through a joint venture between NHP and PMB LLC, obligate us to provide or arrange
   financing for approved developments and provide us with improved terms, including preferred
   returns, a reduction in PMB LLC&amp;#8217;s promote interest and acquisition pricing determined at the time
   of acquisition rather than at the pre-development stage. As of September&amp;#160;23, 2010, we entered into
   a joint venture with PMB Mission Hills 1 LLC (an entity affiliated with Pacific Medical Buildings
   LLC) to develop a medical office building with a total budget of $53.0&amp;#160;million (see &lt;i&gt;PDP Mission
   Hills 1 LLC &lt;/i&gt;below) in accordance with the terms of the Pipeline Agreement. We concurrently entered
   into an agreement with NHP/PMB, PMB LLC and PMB Mission Hills 1 LLC under which the interests in
   the joint venture will be contributed to NHP/PMB subsequent to completion of development in
   accordance with the terms of the Pipeline Agreement.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;During the nine months ended September&amp;#160;30, 2010, NHP/PMB funded $0.5&amp;#160;million in capital and
   tenant improvements at certain facilities.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;All intercompany balances with NHP/PMB have been eliminated for purposes of our consolidated
   financial statements.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;NHP/PMB Gilbert LLC&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of February&amp;#160;1, 2010, we entered into a joint venture with PMB Gilbert LLC (an entity
   affiliated with Pacific Medical Buildings LLC) called NHP/PMB Gilbert LLC (&amp;#8220;Gilbert JV&amp;#8221;) to acquire
   a multi-tenant medical office building. PMB Gilbert LLC contributed the multi-tenant medical office
   building to Gilbert JV, and we contributed $6.3&amp;#160;million in cash. Additionally, we agreed to loan
   Gilbert JV up to $8.8&amp;#160;million as project financing at an interest rate of 7.00%, including $6.8
   million that was disbursed initially and remains outstanding at September&amp;#160;30, 2010. We hold a
   71.17% equity interest in the joint venture and PMB Gilbert LLC holds a 28.83% equity interest. PMB
   Gilbert LLC is the managing member of Gilbert JV, but we consolidate the joint venture in our
   consolidated financial statements. The accounting policies of the joint venture are consistent with
   our accounting policies. Pursuant to a contribution agreement dated as of February&amp;#160;1, 2010, among
   us, NHP/PMB, Pacific Medical Buildings LLC and PMB Gilbert LLC, NHP/PMB may in the future acquire
   Gilbert JV if certain conditions are met.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Net income or loss is allocated between the partners in the joint venture based on the
   hypothetical liquidation at book value method (the &amp;#8220;HLBV method&amp;#8221;). Under the HLBV method, net
   income or loss is allocated between the partners based on the difference between each partner&amp;#8217;s
   claim on the net assets of the partnership at the end and beginning of the period, after taking
   into account contributions and distributions. Each partner&amp;#8217;s share of the net assets of the
   partnership is calculated as the amount that the partner would receive if the partnership were to
   liquidate all of its assets at net book value and distribute the resulting cash to creditors and
   partners in accordance with their respective priorities. Under this method, in any given period, we
   could be recording more or less income than the joint venture has generated or more or less income
   than actual cash distributions received and more or less than what we may receive in the event of
   an actual liquidation. During the nine months ended September&amp;#160;30, 2010, operating cash
   distributions from Gilbert JV of $0.2&amp;#160;million and $4,000 were made to us and to PMB Gilbert LLC,
   respectively.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;All intercompany balances with Gilbert JV have been eliminated for purposes of our
   consolidated financial statements.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;NHP/PMB Pasadena LLC&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of March&amp;#160;1, 2010, we entered into a joint venture with PMB Pasadena LLC (an entity
   affiliated with Pacific Medical Buildings LLC) called NHP/PMB Pasadena LLC (&amp;#8220;Pasadena JV&amp;#8221;) to
   acquire a multi-tenant medical office building. PMB Pasadena LLC contributed the multi-tenant
   medical office building to Pasadena JV, and we contributed $13.5&amp;#160;million in cash. Additionally, we
   provided Pasadena JV with a $56.5&amp;#160;million mortgage loan at an initial interest rate equal to the
   greater of 3.50% or LIBOR plus 165 basis points (increasing to the greater of 5.125% or LIBOR plus
   375 basis points as of April&amp;#160;1, 2010), of which $49.8&amp;#160;million has been funded, and a $3.0&amp;#160;million
   mezzanine loan at an interest rate of 15.00%, both of which remain outstanding at September&amp;#160;30,
   2010. We hold a 71% equity interest in the joint venture and PMB Pasadena LLC holds a 29% equity
   interest. PMB Pasadena LLC is the managing member of Pasadena JV, but we consolidate the joint
   venture in our consolidated financial statements. The accounting policies of the joint venture are
   consistent with our accounting policies. Pursuant to a contribution agreement dated as of March&amp;#160;1,
   2010, among us, NHP/PMB, Pacific Medical Buildings LLC and PMB Pasadena LLC, NHP/PMB may in the
   future acquire Pasadena JV if certain conditions are met.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Net income or loss is allocated between the partners in the joint venture based on the HLBV
   method. During the nine months ended September&amp;#160;30, 2010, operating cash distributions from Pasadena
   JV of $0.1&amp;#160;million were made to us.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;All intercompany balances with Pasadena JV have been eliminated for purposes of our
   consolidated financial statements.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;PDP Mission Hills 1 LLC&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of September&amp;#160;23, 2010, we entered into a joint venture with PMB Mission Hills 1 LLC (an
   entity affiliated with Pacific Medical Buildings LLC) called PDP Mission Hills 1 LLC (&amp;#8220; Mission
   Hills JV&amp;#8221;) to develop a medical office building. We contributed $14.7&amp;#160;million in cash, and PMB
   Mission Hills 1 LLC contributed $1.8&amp;#160;million in cash, and the joint venture acquired the land on
   which the medical office building is to be developed for $15.5&amp;#160;million. The total budget for the
   project is $53.0&amp;#160;million, and construction is expected to commence in late
   2010. We hold an 89.1% equity interest in the joint venture and PMB Mission Hills 1 LLC holds
   a 10.9% equity interest. PMB Mission Hills 1 LLC is the managing member of Mission Hills JV, but we
   consolidate the joint venture in our consolidated financial statements. The accounting policies of
   the joint venture are consistent with our accounting policies. Pursuant to a contribution agreement
   dated as of September&amp;#160;23, 2010, among us, NHP/PMB, PMB LLC and PMB Mission Hills 1 LLC, the
   interests in the joint venture will be contributed to NHP/PMB subsequent to completion of
   development in accordance with the terms of the Pipeline Agreement.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;During the nine months ended September&amp;#160;30, 2010, Mission Hills JV incurred costs of $16.2
   million (including the land acquisition) which is included in the caption &amp;#8220;Development in progress&amp;#8221;
   on our consolidated balance sheets.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Net income or loss is allocated between the partners in the joint venture based on the HLBV
   method. No cash distributions were made during the nine months ended September&amp;#160;30, 2010.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;All intercompany balances with Mission Hills JV have been eliminated for purposes of our
   consolidated financial statements.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;McShane/NHP JV, LLC&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;In December&amp;#160;2007, we entered into a joint venture with McShane called McShane/NHP JV, LLC
   (&amp;#8220;McShane/NHP&amp;#8221;) to invest in multi-tenant medical office buildings. We hold a 95% equity interest
   in the joint venture and McShane holds a 5% equity interest. McShane is the managing member of
   McShane/NHP, but we consolidate the joint venture in our consolidated financial statements. The
   accounting policies of the joint venture are consistent with our accounting policies.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;Cash distributions from McShane/NHP are made in accordance with the members&amp;#8217; ownership
   interests and will continue to be made until specified returns are achieved. As the specified
   returns are achieved, McShane will receive an increasing percentage of the cash distributions from
   the joint venture. During the nine months ended September&amp;#160;30, 2010, operating cash distributions
   from McShane/NHP of $0.9&amp;#160;million and $48,000 were made to us and to McShane, respectively.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;As of September&amp;#160;30, 2010, McShane/NHP owned seven multi-tenant medical office buildings
   located in one state.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;During the nine months ended September&amp;#160;30, 2010, McShane/NHP funded $0.9&amp;#160;million in capital
   and tenant improvements at certain facilities.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;All intercompany balances with McShane/NHP have been eliminated for purposes of our
   consolidated financial statements.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%"&gt;&lt;i&gt;NHP/Broe, LLC and NHP/Broe II, LLC&lt;/i&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 8%"&gt;On August&amp;#160;21, 2009, we acquired for $4.3&amp;#160;million the 10% and 5% noncontrolling interests held
   by The Broe Companies in NHP/Broe, LLC (&amp;#8220;Broe I&amp;#8221;) and NHP/Broe II, LLC (&amp;#8220;Broe II&amp;#8221;), respectively.
   As a result of this acquisition, we now have direct ownership of the 36 multi-tenant medical office
   buildings located in nine states previously owned by Broe I and Broe II. Activity subsequent to
   August&amp;#160;21, 2009 related to these facilities is included in our consolidated activity for wholly
   owned real estate properties (see Note 3). Prior to our acquisition of Broe&amp;#8217;s interests, we
   consolidated both joint ventures in our consolidated financial statements in accordance with ASC
   810.
   &lt;/div&gt;
   &lt;/div&gt;
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