Exhibit 10.4

THIRD AMENDMENT TO PURCHASE AND SALE AGREEMENT

THIS THIRD AMENDMENT TO PURCHASE AND SALE AGREEMENT (this “Third Amendment”), is entered into as of August 8, 2011, by and between WELLS/FREMONT ASSOCIATES, a Georgia joint venture ("Seller"), and LIGHTHOUSE WORLDWIDE SOLUTIONS, INC., a California corporation ("Purchaser"). The parties hereto are sometimes jointly called the “Parties.”

R E C I T A L S:

A.Buyer and Seller have entered into that certain PURCHASE AND SALE AGREEMENT effective as of June 3, 2011 (“Original Purchase Agreement”), as amended by that certain FIRST AMENDMENT TO PURCHASE AND SALE AGREEMENT dated as of July 20, 2011 (“First Amendment”) and that certain SECOND AMENDMENT TO PURCHASE AND SALE AGREEMENTED dated as of July 29, 2011 (“Second Amendment”, the Original Purchase Agreement, First Amendment and Second Amendment are collectively referred to herein as “Purchase Agreement”), for the purchase and sale of that certain real property more particularly described in the Purchase Agreement (the “Property”). Buyer and Seller desire to extend the Financing Contingency Period on the terms and conditions contained herein.

B.Buyer and Seller desire to extend the Financing Contingency Period on the terms and conditions contained herein.

NOW, THEREFORE, in consideration of the premises and the respective covenants and agreements hereinafter set forth, the Parties hereby agree as follows:

1.Financing Contingency Period. The Financing Contingency Period is extended such that it expires as of 5:00 pm, Pacific Time, August 9, 2011.

2.Binding Effect. This Third Amendment shall be binding upon and inure to the benefit of the Parties and their heirs, executors, administrators, successors, legal representatives and permitted assigns.

3.Counterparts. This Third Amendment may be executed in counterparts, all of which together shall constitute one agreement binding on all of the Parties, notwithstanding that all such parties are not signatories to the original or the same counterpart.

4.Confirmation of the Purchase Agreement. Except as set forth in this Third Amendment, the Purchase Agreement is not being amended, supplemented or otherwise modified, and all of the undersigned agree that the terms, conditions and agreements set forth in the Purchase Agreement are hereby ratified and confirmed and shall continue in full force and effect. Any capitalized terms not defined herein shall have the meanings ascribed to them in the Purchase Agreement.

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THIRD AMENDMENT TO PURCHASE AND SALE AGREEMENT

IN WITNESS WHEREOF, the Parties have executed this Third Amendment as of the day first above written.



Seller: WELLS/FREMONT ASSOCIATES a Georgia Joint Venture Piedmont Operating Partnership, LP a Delaware limited partnership By:Piedmont Office Realty Trust, Inc. a Maryland corporation Its:General Partner By: /s/ Laura Moon Name: Laura Moon Its: SVP & CAO FUND X AND FUND XI ASSOCIATES A Georgia joint venture By: Wells Real Estate Fund X, L.P. a Georgia limited partnership By: Wells Partners, L.P. a Georgia limited partnership as General Partner By: Wells Capital, Inc. a Georgia corporation as General Partner By: /s/ Randall D. Fretz Name: Randall D. Fretz Its: Sr. Vice President By: /s/ Randall D. Fretz Name: Leo F. Wells, III, as General Partner, by and through Randall D. Fretz, as attorney in fact	Buyer: LIGHTHOUSE WORLDWIDE SOLUTIONS, INC. a California corporation By: /s/ Dr. Tae Yun Kim Name: Title:

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By:Wells Real Estate Fund XI, L.P. a Georgia limited partnership By:Wells Partners, L.P. a Georgia limited partnership as General Partner By:Wells Capital, Inc. a Georgia corporation as General Partner By: /s/ Randall D. Fretz Name: Randall D. Fretz Its: Sr. Vice President By: /s/ Randall D. Fretz Name: Leo F. Wells, III, as General Partner, by and through Randall D. Fretz, as attorney in fact

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WELLS REAL ESTATE FUND X L P 10-Q