system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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the Fifteen(15 th ) of any month is not a business day) shall be deemed overdue and you shall pay to us, in addition to the overdue payment, interest on such overdue amount at the rate of one and one-half percent (1.5%) per month or the maximum rate permitted by law, whichever is less. Interest shall accrue from the original due date until payment is received in full. Our right to such interest shall be in addition to any other remedies we may have, including, without limitation, the right of set-off to withdraw or retain, from time to time and without notice to you, any amounts due and unpaid by us to you. You shall not be entitled to set-off any payments required to be made under this Section 4 against any monetary claim you may have against us. 5 Source: SOUPMAN, INC., 8-K, 8/14/2015 4.5 Late Fee; Insufficient Funds Fee In the event you fail to provide us with any report we require on or before the date we require it, you agree to pay to us a late fee in the amount of Two Hundred Fifty Dollars ($250). In addition, if, for any reason, any payment owed by you to us is denied by your bank due to insufficient funds in your account, then you shall, in addition to applicable interest as described in Section 4.4 above, pay us an insufficient funds fee in the amount of Two Hundred Fifty Dollars ($250). If you incur three (3) late fees or insufficient funds fees within any twelve (12) month period, we will have the right to terminate this Agreement without providing you an opportunity to cure the default. 4.6 Unit Franchise Agreements and Revenue Reports You shall submit to us copies of all Unit Franchise Agreements executed with Unit Franchisees within ten (10) days of the date of their execution, together with a copy of all checks presented to you at closing. You shall prepare and submit to us a monthly report, not later than the first (1 s t ) day of each month, of Franchise Sales Revenue generated by you during the previous calendar month. Contemporaneously with the submission of the Franchise Sales Revenue report, you shall prepare and submit to us a monthly report, in such form and including such detail as we require, reflecting royalty fees paid and owed to you by your Unit Franchisees for the previous calendar month. Any report not actually received by us when due shall be deemed overdue and you shall pay us a late charge as described above. 4.7 Security Interest In order to secure payment of all Unit Franchise Performance Royalty Fees, Franchise Sales Royalty Fees, National Advertising Fund Contributions, and all other sums that may become due to us or our affiliates from you under this Agreement, and to secure your performance of all obligations of any kind, whenever and however incurred, in favor of us or our affiliates: 4.7.1 You hereby grant us a security interest in and to all equipment, furniture, fixtures, inventory, supplies and vehicles used in connection with the Franchised Business, now or hereafter acquired by you, together with all accounts, payment intangibles, attachments, accessories, additions, substitutions and replacements, all cash and non-cash proceeds derived from insurance or the disposition of such assets, all of your rights to use the Proprietary Marks, patents, copyrights and their registrations, trade secret information and other proprietary rights, and all rights granted, owned or licensed to you under this Agreement for the use of the Proprietary Marks, trade names, trade styles, patents, copyrights, trade secret information and other proprietary rights. You hereby authorize us to prepare and file all Uniform Commercial Code ("UCC") financing statements and other documents necessary or desirable to evidence, perfect and continue the priority of this security interest under the UCC. 4.7.2 If you are and remain in good standing under this Agreement and all other agreements with us and our affiliates, we will consent to your grant of an additional security interest in the Franchised Business or in any of the assets of the Franchised Business if the conditions set forth in Section 12.4 of this Agreement are met. 4.7.3 If you are in default of any of the terms and conditions of this Agreement or any other agreements between us and our affiliates and you, we may, in our sole and absolute discretion, exercise our rights with respect to our security interest. In such event, you shall be and remain liable
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Extract the exact clause related to "Expiration Date" from the excerpt above.