The investments in unconsolidated joint ventures consist of the following at September 30, 2011:

Certain of the Company's joint venture agreements include provisions whereby, at certain specified times, each partner has the right to initiate a purchase or sale of its interest in the joint ventures at an agreed upon fair value. Under these provisions, the Company is not compelled to purchase the interest of its outside joint venture partners.

The combined summarized balance sheets of the unconsolidated joint ventures are as follows:


	September 30, 2011			December 31, 2010
	(in thousands)
ASSETS
Real estate and development in process, net	$	4,991,083		$	5,028,851
Other assets		680,091			749,308

Total assets	$	5,671,174		$	5,778,159

LIABILITIES AND MEMBERS'/PARTNERS' EQUITY
Mortgage and notes payable	$	3,139,362		$	3,151,220
Other liabilities		907,144			969,082
Members'/Partners' equity		1,624,668			1,657,857

Total liabilities and members'/partners' equity	$	5,671,174		$	5,778,159

Company's share of equity	$	898,910		$	924,235
Basis differentials(1)		(128,444	)		(156,983	)

Carrying value of the Company's investments in unconsolidated joint ventures	$	770,466		$	767,252

(1)

This amount represents the aggregate difference between the Company's historical cost basis and the basis reflected at the joint venture level, which is typically amortized over the life of the related assets and liabilities. Basis differentials occur from impairment of investments and upon the transfer of assets that were previously owned by the Company into a joint venture. In addition, certain acquisition, transaction and other costs may not be reflected in the net assets at the joint venture level.

The combined summarized statements of operations of the unconsolidated joint ventures are as follows:


	For the three months ended September 30,						For the nine months ended September 30,
	2011			2010			2011			2010
	(in thousands)						(in thousands)
Total revenue(1)	$	150,101		$	155,126		$	440,733		$	457,217
Expenses
Operating		44,584			45,546			129,698			130,083
Depreciation and amortization		46,773			50,548			145,653			164,763

Total expenses		91,357			96,094			275,351			294,846
Operating income		58,744			59,032			165,382			162,371
Other expenses
Interest expense		57,699			59,120			172,467			176,705
Loss on guarantee obligation		—			3,581			—			3,581
Impairment loss		39,384			—			39,384			—

Net loss	$	(38,339	)	$	(3,669	)	$	(46,469	)	$	(17,915	)

Company's share of net loss	$	(23,231	)	$	(487	)	$	(28,570	)	$	(7,207	)
Basis differential		25,024			3,125			28,539			7,918
Elimination of inter-entity interest on partner loan		9,533			8,927			28,215			26,229

Income from unconsolidated joint ventures	$	11,326		$	11,565		$	28,184		$	26,940

(1)

Includes straight-line rent adjustments of $6.7 million and $5.9 million for the three months ended September 30, 2011 and 2010, respectively, and $14.8 million and $19.8 million for the nine months ended September 30, 2011 and 2010, respectively. Includes net "above-" and "below-market" rent adjustments of $28.3 million and $30.5 million for the three months ended September 30, 2011 and 2010, respectively, and $87.0 million and $97.6 million for the nine months ended September 30, 2011 and 2010, respectively.

On March 16, 2011, the Company's Value-Added Fund extended the maturity date by two months to May 31, 2011 of the mortgage loan collateralized by its Mountain View Technology Park property located in Mountain View, California totaling approximately $24.7 million. The mortgage loan bears interest at a variable rate equal to LIBOR plus 1.50% per annum and was scheduled to mature on March 31, 2011. On June 29, 2011, the Company's Value-Added Fund extended the maturity date to November 15, 2011.

On March 26, 2011, a joint venture in which the Company has a 30% interest removed from service and commenced the redevelopment of 500 North Capitol Street, NW located in Washington, DC. On January 18, 2011, the joint venture entered into a lease with a law firm for approximately 171,000 square feet of space (See Note 13).

On March 31, 2011, a joint venture in which the Company has a 50% interest refinanced its construction loan collateralized by Annapolis Junction located in Annapolis, Maryland. The construction loan totaling approximately $42.7 million bore interest at a variable rate equal to LIBOR plus 1.00% per annum and was scheduled to mature on September 12, 2011. The new mortgage loan totaling approximately $42.3 million bears interest at a variable rate equal to LIBOR plus 1.75% per annum and matures on March 31, 2018 with one, three-year extension option, subject to certain conditions.

On June 3, 2011, a joint venture in which the Company has a 50% interest amended its joint venture agreement to add a new development project to its Annapolis Junction property located in Annapolis, Maryland. The outside joint venture partner contributed the improved parcel of land and the Company contributed cash for its 50% interest. The development project is an approximately 120,000 net rentable square foot Class A office project.

On June 28, 2011, the Company's Value-Added Fund modified the mortgage loan collateralized by its Mountain View Research Park property located in Mountain View, California. The mortgage loan totaling approximately $112.3 million bore interest at a variable rate equal to LIBOR plus 1.75% per annum and had matured on May 31, 2011. The new mortgage loan totaling $92.0 million bears interest at a variable rate equal to LIBOR plus 2.50% per annum and matures on May 31, 2014. In connection with the loan modification, the joint venture repaid approximately $20.3 million of the previous mortgage loan utilizing unfunded capital commitments from the joint venture's partners on a pro rata basis, existing cash reserves and the proceeds from a loan from the Company's Operating Partnership. The loan from the Company's Operating Partnership consists of an agreement to lend up to $12.0 million to the Company's Value-Added Fund, of which approximately $6.4 million has been advanced. The loan from the Operating Partnership bears interest at a fixed rate of 10.0% per annum and matures on May 31, 2014.

On August 12, 2011, an unconsolidated joint venture in which the Company has a 60% interest entered into an agreement to sell Two Grand Central Tower located in New York City for approximately $401.0 million, including the assumption by the buyer of approximately $176.6 million of mortgage indebtedness (See Note 13). Two Grand Central Tower is an approximately 650,000 net rentable square foot Class A office tower. The unconsolidated joint venture's carrying value of the net assets of the property aggregated approximately $425.7 million. As a result, pursuant to the provisions of ASC 360 "Property, Plant and Equipment" ("ASC 360") (formerly known as SFAS No. 144 "Accounting for the Impairment or Disposal of Long Lived Assets"), the unconsolidated joint venture recognized a non-cash impairment loss of approximately $39.4 million, which is equal to the difference between the sale price less cost to sell and the carrying value of the net assets of the property. Because the Company had previously recognized an impairment loss on its investment in the unconsolidated joint venture under the provisions of ASC 323 "Investments-Equity Method and Joint Ventures" ("ASC 323") (formerly known as Accounting Principles Board Opinion No. 18 "The Equity Method of Accounting for Investments in Common Stock" ("APB No. 18")), no additional impairment loss has been recognized by the Company.