merger, consolidation, sale, lease or other disposition and do not extend to any assets other than those of the person merged with or into, or consolidated with, us or a Subsidiary of ours or such property sold, leased or disposed of;
(6) Liens in favor of the United States of America or any state, territory or possession thereof (or the District of Columbia), or any department, agency, instrumentality or political subdivision of the United States of America or any state, territory or possession thereof (or the District of Columbia), to secure partial, progress, advance or other payments pursuant to any contract or statute or to secure any Debt incurred for the purpose of financing all or any part of the purchase price of or the cost of constructing or improving the property subject to such Liens;
(7) Liens securing the debt securities of such series;
(8) Liens created in connection with a project financed with, or created to secure,Non-recourse Obligations;
(9) Liens to secure bonds, notes, debentures or similar instruments on which the interest is exempt from federal income tax; and
(10) extensions, renewals, refinancings or replacements (in whole or in part) of any Liens or Debt which is secured by Liens that were permitted to be incurred by the indenture;provided, however, that (a) the principal or accreted amount of any Debt of ours or any of our Significant Subsidiaries secured by such Lien immediately after such extension, renewal, refinancing or replacement shall not exceed the sum of the principal or accreted amount, as the case may be, of any Debt of ours or any of our Significant Subsidiaries so secured immediately prior to such extension, renewal, refinancing or replacement plus any costs and expenses (including, without limitation, any fees, premiums and penalties) related to such extension, renewal, refinancing or replacement and (b) such extension, renewal, refinancing or replacement Liens are limited to all or part of the same Principal Property (and any improvements thereon), shares of Capital Stock of any Significant Subsidiary or Intercompany Debt which secured any Debt of ours or any of our Significant Subsidiaries immediately prior to such extension, renewal, refinancing or replacement.
Notwithstanding the foregoing, we and our Significant Subsidiaries may, without securing the debt securities of such series or any other debt securities issued under the indenture, issue, incur, create, assume or guarantee Debt secured by any Liens which would otherwise be subject to the restrictions set forth in the immediately preceding paragraph if, immediately after giving effect thereto and, if applicable, to the application of any proceeds therefrom to repay Debt on a pro forma basis, our Aggregate Debt does not exceed the greater of (1) 20% of our Consolidated Net Tangible Assets, determined as of the date of such issuance, incurrence, creation, assumption or guarantee, and (2) $500 million. (Section 4.1 of the supplemental indenture)
Limitation on Sale and Lease-Back Transactions
In the indenture, we covenant and agree, for the benefit of the holders of the debt securities of each series, that we will not, nor will we permit any Significant Subsidiary to, enter into any Sale and Lease-Back Transaction with respect to any Principal Property, unless:
(1) such Sale and Lease-Back Transaction involves a lease for a term of not more than three years;
(2) such Sale and Lease-Back Transaction is between us and one of our Subsidiaries or between any Subsidiaries of ours;
(3) we or such Significant Subsidiary would be entitled, at the time of such Sale and Lease-Back Transaction, to incur Debt secured by a Lien on the Principal Property involved in such Sale and Lease-Back Transaction at least equal in amount to the Attributable Debt with respect to such Sale and Lease-Back Transaction, without equally and ratably securing the debt securities of such series, pursuant to the first paragraph under “—Limitation on Liens” above;
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