Subordination to Mortgage This Lease, and any sublease entered into by Tenant under the provisions of this Lease, shall be subject and subordinate to any ground lease, mortgage, deed of trust, sale/leaseback transaction or any other hypothecation for security now or hereafter placed upon the Building, the Property, the Center, or any of them, and the rights of any assignee of Landlord or of any ground lessor, mortgagee, trustee, beneficiary or leaseback lessor under any of the foregoing, and to any and all advances made on the security thereof and to all renewals, modifications, consolidations, replacements and extensions thereof; PROVIDED, however, that such subordination in the case of any future ground lease, mortgage, deed of trust, sale/leaseback transaction or any other hypothecation for security placed upon the Building, the Property, the Center, or any of them shall be conditioned on Tenant's receipt from the ground lessor, mortgagee, trustee, beneficiary or leaseback lessor of a Non-Disturbance Agreement in a form reasonably acceptable to Tenant (i) confirming that so long as Tenant is not in material default hereunder beyond any applicable cure period (for which purpose the occurrence of any event of default under Section 16.1 hereof shall be deemed to be "material"), Tenant's rights hereunder shall not be disturbed by such person or entity and (ii) agreeing that the benefit of such Non-Disturbance Agreement shall be transferable to any transferee under a Permitted Transfer and to any other assignee or subtenant that is acceptable to the ground lessor, mortgagee, trustee, beneficiary or leaseback lessor at the time of transfer. If any mortgagee, trustee, beneficiary, ground lessor, sale/leaseback lessor or assignee elects to have this Lease be an encumbrance upon the Property prior to the lien of its mortgage, deed of trust, ground lease or leaseback lease or other security arrangement and gives notice thereof to Tenant, this Lease shall be deemed prior thereto, whether this Lease is dated prior or subsequent to the date thereof or the date of recording thereof. Tenant, and any sublessee, shall execute such documents as may reasonably be requested by any mortgagee, trustee, beneficiary, ground lessor, sale/leaseback lessor or assignee to evidence the subordination herein set forth, subject to the conditions set forth above, or to make this Lease prior to the lien of any mortgage, deed of trust, ground lease, leaseback lease or other security arrangement, as the case may be. Upon any default by Landlord in the performance of its obligations under any mortgage, deed of trust, ground lease, leaseback lease or assignment, Tenant (and any sublessee) shall, notwithstanding any subordination hereunder, attorn to the mortgagee, trustee, beneficiary, ground lessor, leaseback lessor or assignee thereunder upon demand and become the tenant of the successor in interest to Landlord, at the option of such successor in interest, and shall execute and deliver any instrument or instruments confirming the attornment herein provided for. Promptly following execution of this Lease, Landlord shall use commercially reasonable efforts to obtain a Non-Disturbance Agreement comparable to that described above in this Section 17.1 from any mortgagee, trustee, beneficiary, ground lessor or leaseback lessor holding an interest in the Property on the date of this Lease (but Landlord hereby advises Tenant that in fact there is no mortgagee, trustee, beneficiary, ground lessor or leaseback lessor holding an interest in the Property on the date of this Lease).