TWELFTH AMENDMENT TO LEASE

THIS TWELFTH AMENDMENT TO LEASE (this "Twelfth Amendment")is made this 28th day of October, between **Spieker Properties, L.P.**, aCalifornia limited partnership, (the "Landlord"), and Siebel Systems,Inc., (the "**Tenant**").

WHEREAS, Landlord and Tenant entered into a Lease dated August 24,1994, (as amended, the "Lease"), for those certain premises located at1900 Powell Street, Emeryville, California (the "Premises"), as morefully described in the Lease.  Capitalized terms used but not otherwise definedherein shall have the meanings given them in the Lease; and

	**WHEREAS**, Landlord and Tenant desire to modify the Leaseaccordingly.

	**NOW, THEREFORE**, in consideration of the covenants and agreementscontained herein the parties hereby mutually agree as follows:

Premises
.
  The Premises shall be increasedto include approximately three thousand three hundred seventy (3,370) squarefeet of rentable area (the "Expansion Premises"), which ExpansionPremises includes a portion of the Building common area and is located on thetenth (10th) floor of the Building.  The  Expansion Premises, are approximatelyas shown on the attached 
Exhibit A
 and outlined in red.

**Term
.  The Term with respect to theExpansion Premises shall commence upon the date which Landlord delivers thePremises to Tenant, which is estimated to be November 1, 1999, (the"
Delivery Date
") and shall expire on March 31, 2001. Landlordshall have no liability to Tenant for any damages resulting from any delay indelivering possession of the Expansion Premises to Tenant; provided, however,that Landlord shall make reasonable efforts deliver possession of the ExpansionPremises to Tenant as provided herein.

**Occupancy Density
.
  Upon the Delivery Date,the Occupancy Density for the Expansion Premises shall be 60people.

4.	**Rent.**  Base Rent for the ExpansionPremises shall be as follows:

Delivery Date through 3/31/01: 
Seven thousand five hundred eighty-two and 50/100ths ($7,582.50) per monthplus operating expenses per Paragraph 4.3 of the Lease over the calendar year1999.  

Tenant's Proportionate Share
.
  Upon theDelivery Date, Tenant's proportionate share for the Expansion Premises shall be1.56%.  Tenant's Proportionate Share for the Premises, including the ExpansionPremises, shall be 36.16%.

**Tenant Improvements.
  Tenant agrees toaccept the Expansion Premises "as is" condition; provided, however,that, Landlord shall provide Tenant with a Tenant Improvement Allowance in theamount of $3,370.00. Said Tenant Improvement Allowance shall be disbursedpursuant to the terms and conditions of Paragraph 6 of Amendment Number Ten tothe Lease. 

All other terms and conditions of the Lease shall remain infull force and effect and shall apply to the Premises, including the ExpansionPremises.

Except as expressly modified above, all terms and conditions of the Leaseremain in full force and effect and are hereby ratified and confirmed.
**IN WITNESS WHEREOF, the parties hereto have entered into this EleventhAmendment as of the date first written above.

 

LANDLORD**:						**TENANT**:**
Spieker Properties, L.P., 				Siebel Systems, Inc.,

a California limited partnership			a Delaware corporation

By:	Spieker Properties, Inc.	

	a Maryland corporation

	its General Partner

 

  By:_____________________________		  By:_____________________	

 	John Winther					  	______________________

  Its:	Senior Vice President			  	Its:	______________________

						

 

 

 

 

 

 

 

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