MEMBERSHIP INTEREST ASSIGNMENT AGREEMENT

THIS MEMBERSHIP INTEREST ASSIGNMENT AGREEMENT (the “Agreement”) is made as of
March 23, 2007 by Triple Net Properties, LLC, a Virginia limited liability
company (the “Assignor”) and NNN Healthcare/Office REIT Holding, L.P., a
Delaware limited partnership (the “Assignee”).

RECITALS:

A. As of the date hereof, Assignor owns a one hundred percent (100%) membership
interest (the “Interest”) in NNN Lenox Medical Land, LLC, a Delaware limited
liability company (the “Company”).

B. As of the date hereof, the Company owns fee simple title to certain vacant
land known as (i) Parcels 410 and 419 located in Shelby County, Memphis
Tennessee, as described in more particularity on Exhibit A, attached hereto and
incorporated by reference herein (collectively, the “Property”)

C. Assignor and Assignee entered into a Membership Interest Purchase and Sale
Agreement dated March 20th, 2007 (“Contract”), whereby Assignee agreed to
acquire the Interest from Assignor.

D. Assignor wishes to transfer to Assignee, and Assignee wishes to obtain from
Assignor, the Interest for the consideration and in the manner and on the terms
and conditions hereinafter set forth.

NOW, THEREFORE, for and in consideration of (i) Ten Dollars ($10.00) cash,
(ii) the mutual covenants contained herein, and (iii) other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties agree as follows:

1. Transfer of Interest. Assignor hereby conveys, assigns, transfers and sets
over to Assignee the Interest, and Assignee hereby accepts from Assignor, all of
Assignor’s right, title and interest in the Interest assigned to Assignee, as of
the date hereof.

2. Representations and Warranties of Assignor.

(a) Assignor represents and warrants that (i) Assignor is the lawful owner of
the Interest free and clear of all liens, encumbrances and other claims of all
third persons whatsoever and (ii) Assignor has the absolute right to transfer
the Interest.

(b) Assignee represents and warrants that Assignee’s acquisition of the Interest
is made for Assignee’s account for investment purposes only, and not with a view
to the resale or distribution thereof.

(c) These representations and warranties are intended to and shall survive the
transfer of the Interest pursuant to this Agreement.

3. Indemnification. Except as expressly set forth in the Contract, Assignee
agrees to indemnify Assignor against and hold Assignor harmless from, all
losses, liabilities, costs and other expenses, including reasonable attorney’s
fees, which Assignor may incur from (a) the inaccuracy of any representation or
the breach of any warranty by Assignee hereunder or from (b) events arising out
of the operations of the business of the Property after the date of this
Agreement. Except as expressly set forth in the Contract, Assignor agrees to
indemnify Assignee against and hold Assignee harmless from, all losses,
liabilities, costs and other expenses, including reasonable attorney’s fees,
which Assignee may incur from (a) the inaccuracy of any representation or the
breach of any warranty by Assignor hereunder or from (b) events arising out of
the operations of the business of the Property prior to the date hereof. The
representations and warranties of Assignee and Assignor contained in this
Agreement shall survive the transfer of the Interest.

4. Release. Except as expressly set forth in the Contract, Assignor hereby
releases Assignee, and its affiliates, agents, representatives and employees
from any and all liability relating to the Property during the Assignor’s period
of ownership. Except as expressly set forth in the Contract, Assignee hereby
release Assignor and its affiliates, agents, representative and employees from
any and all liability relating to the Property, during the Assignee’s period of
ownership. For purposes of the foregoing, Assignor hereby specifically waives
the provisions of Section 1542 of the California Civil Code and any similar law
of any other jurisdiction. Section 1542 provides:

A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR
SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF EXECUTING THE RELEASE, WHICH IF
KNOW BY HIM MUST HAVE MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR.

ASSIGNOR HEREBY EXPRESSLY ACKNOWLEDGES THAT BUYER HAS CAREFULLY REVIEWED THIS
SECTION AND DISCUSSED IT WITH LEGAL COUNSEL AND THAT THE PROVISIONS OF THIS
SECTION ARE A MATERIAL PART OF THIS AGREEMENT.

Assignor’s Initials: ARB

To the extent required under applicable law, the parties agree that the
disclaimers in this Agreement are “conspicuous” disclaimers for purposes of any
applicable law.

5. Enforceability. This Agreement has been duly executed by and delivered by and
constitutes a valid and binding agreement of the parties and is enforceable
against the parties in accordance with its terms.

6. Benefit. This Agreement shall be binding upon, and shall inure to the benefit
of, the parties hereto and their respective assigns and successors in title or
interest.

7. Applicable Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Indiana, without regard to any
conflicts of law provisions or principles thereof to the contrary.

8. Entire Agreement and Modification. This document contains the entire
agreement between the parties hereto with respect to the subject matter herein.
This Agreement shall not be modified unless, and then only to the extent that, a
written modification is executed by all of the parties hereto or their
respective successors or assigns.

9. Counterparts. This Agreement may be executed in counterparts, and any
executed counterparts shall be binding the parties hereto and inure to their
benefit as though all parties were signatory to the same counterpart.

[SIGNATURES APPEAR ON THE FOLLOWING PAGES]

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the first
date written above.

         
ASSIGNOR:
  TRIPLE NET PROPERTIES, LLC,  

 
            a Virginia limited liability company

 
       
 
  By: /s/ Andrea R. Biller  

 
             

 
       
 
  Name: Andrea R. Biller  

 
             

 
       
 
  Title: Executive Vice President  

 
             

 
       

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        ASSIGNEE:   NNN Healthcare/Office REIT Holding, L.P.,

 
       
 
  a Delaware limited partnership  

 
       
 
  By:   NNN Healthcare/Office REIT, Inc.,
a Maryland corporation
its General Partner
 
       
 
      By: /s/ Scott D. Peters
 
       
 
       
 
      Name: Scott D. Peters
 
       
 
       
 
      Title: CEO
 
       
 
       

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