Riverbed Technology (RVBD)

Tenant Estoppel Certificate

The undersigned, as Tenant under that certain Lease Agreement (the “Lease”) made and entered                  into as of , 20     and between GLL FREMONT STREET PARTNERS, a California partnership organized under the laws of California, as Landlord, and the undersigned as Tenant, for Premises on the              through              floors of the Building located at 199 Fremont Street, San Francisco, California, hereby certifies as follows:

1. Attached hereto as Exhibit A is a true and correct copy of the Lease and all amendments and modifications thereto. The documents contained in Exhibit A represent the entire agreement between the parties as to the Premises.

2. The undersigned has commenced occupancy of the Premises described in the Lease, currently occupies the Premises, and the Commencement Date occulted on                 .

3. The Lease is in full force and effect and has not been modified, supplemented or amended in any way except as provided in Exhibit A.

4. Tenant has not transferred, assigned, or sublet any portion of the Premises nor entered into any license or concession agreements with respect thereto except as follows:

5. Tenant has not voluntarily prepaid any amounts owing under the Lease to Landlord in excess of thirty (30) days.

6. The date of                 , 20    , is the Commencement Date for the Term for the Premises, as defined in the Lease.

7. The date of                 , is the scheduled Expiration Date of the Term; and

8. The Premises consist of                  rentable square feet.

9. The period of                 , 20     through                 , 20    , is the First Window Period during which Tenant may elect to lease the First Expansion Space.

10. The period of                 , 20     through                 , 20    , is the Second Window Period during which time Tenant may elect to lease the Second Expansion Space.

11. The Termination Date for the cancellation of the Lease with respect to the Early Termination Premises is                         .

12. To Tenant’s actual knowledge, all conditions of the Lease to be performed by Landlord necessary to the enforceability of the Lease have been satisfied and Landlord is not in default thereunder, except as follows:                                                                                  .

13. No rental has been paid in advance and no security has been deposited with Landlord except as provided in the Lease, except as follows:                                                                                  .

14. As of the date hereof, there are no existing defenses or offsets that the undersigned has, which preclude enforcement of the Lease by Landlord, provided that none of the foregoing shall negate Tenant’s audit rights set forth in Section 6.8 of the Lease.

15. All monthly installments of Minimum Monthly Rent and all other rent have been paid when due through                                 . The current monthly installment of Minimum Monthly Rent is $            .

16. The undersigned acknowledges that this Estoppel Certificate may be delivered to Landlord’s existing or prospective mortgagee, or a prospective purchaser, and acknowledges that it recognizes that if same is done, said mortgagee, or prospective purchaser will be relying upon the statements contained herein.

17. If Tenant is a corporation, limited liability company, or partnership, each individual executing this Estoppel Certificate on behalf of Tenant hereby represents and warrants that Tenant is a duly formed and existing entity qualified to do business in the state in which the Building is located and that Tenant has full right and authority to execute and deliver this Estoppel Certificate and that each person signing on behalf of Tenant is authorized to do so.

18. Executed at                          on the              day of             , 20    .