EXHIBIT 10.18FIRST AMENDMENT TO OFFICE BUILDING LEASE

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Exhibit 10.18

FIRST AMENDMENT TO OFFICE BUILDING LEASE

        This FIRST AMENDMENT TO OFFICE BUILDING LEASE (this " First Amendment ") is made and entered into as of August 26, 2005, by and between KILROY REALTY, L.P., a Delaware limited partnership (" Landlord "), and THE RYLAND GROUP, INC., a Maryland corporation (" Tenant ").

R E C I T A L S :

        A.    Landlord and Tenant entered into that certain Office Lease dated as of December, 1999 (the " Lease "), whereby Landlord leased to Tenant and Tenant leased from Landlord a total of approximately 32,946 rentable (31,388 usable) square feet of space (the " Premises "), comprised of (i) approximately 7,622 rentable (6,686 usable) square feet of space commonly known as Suite 100, and (ii) approximately 25,324 rentable (24,702 usable) square feet of space commonly known as Suite 400, located on the first (1 ^st ) and fourth (4 ^th ) floors, respectively, of that certain office building located at 24025 Park Sorrento, Calabasas, California (the "Building" ), which Building forms a part of that certain multi-building project commonly known as "Calabasas Park Centre" (the " Project ").

        B.    Tenant desires to extend the term of the Lease, and in connection therewith, Landlord and Tenant desire to amend the Lease on the terms and conditions contained herein.

A G R E E M E N T :

        NOW, THEREFORE, in consideration of the foregoing recitals and the mutual covenants contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows.

        1.      Defined Terms.     All capitalized terms when used herein shall have the same respective meanings as are given such terms in the Lease unless expressly provided otherwise in this First Amendment.

        2.      Extended Term.     Landlord and Tenant acknowledge that Tenant's lease of the Premises is scheduled to expire on October 31, 2006, pursuant to the terms of the Lease. Notwithstanding any provision to the contrary set forth in the Lease, the term of Tenant's lease of the Premises is hereby extended for a period of ten (10) years commencing on November 1, 2006 (the " Extended Term Commencement Date "), and ending on October 31, 2016 (the " Extended Term Expiration Date "), unless sooner terminated as provided in the Lease, as hereby amended. The period of time commencing on the Extended Term Commencement Date and ending on the Extended Term Expiration Date shall be referred to herein as the " Extended Term ."

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        3.      Base Rent.     

                3.1      Monthly Base Rent.     Prior to the Extended Term Commencement Date, Tenant shall continue to pay Monthly Base Rent for the Premises in accordance with the terms of the Lease. Notwithstanding the foregoing or any provision to the contrary set forth in the Lease, commencing on the Extended Term Commencement Date and continuing throughout the Extended Term, Tenant shall pay Monthly Base Rent for the Premises in accordance with the following schedule:

*

The installments of Monthly Base Rent payable by Tenant for the first three (3) months of the Extended Term ( i.e., the period from November 1, 2006 through January 31, 2007) shall be subject to reduction in accordance with the terms set forth in Section 3.2 of this First Amendment.

                3.2      Abatement of Monthly Base Rent.     Notwithstanding any contrary provision set forth in Section 3.1 , above, provided that Tenant is not then in default under the Lease (beyond all applicable notice and cure periods), as amended hereby, Tenant's Monthly Base Rent for that portion of the Premises consisting of Suite 100 only ( i.e., for 7,622 rentable square feet of space of the Premises only) shall be abated for the first three (3) months of the Extended Term, thereby reducing each installment of Monthly Base Rent payable by Tenant for the three (3) month period commencing on the November 1, 2006 ( i.e., the Extended Term Commencement Date) and ending on January 31, 2007 to Seventy-Two Thousand One Hundred Seventy-Three and 40/100 Dollars ($72,173.40) ( i.e., $2.85 per rentable square foot of Suite 400 only).

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        4.      Operating Expenses.     Prior to the Extended Term Commencement Date, Tenant shall continue to pay Tenant's Percentage of Operating Expenses for the Premises in accordance with the terms of the Lease. Notwithstanding any provision to the contrary set forth in the Lease or this First Amendment, commencing on the Extended Term Commencement Date