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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to termination, multiplied by the number of unexpired months remaining in the current year of the Agreement. (j) "End of Agreement Fee" means the fee, in addition to any other amounts due, payable to DD (when this Agreement is terminated as further described in Section 18(f)) that is equal to two (2) times the last month's Promotional Fee earned by DD during the last month of the Agreement. (k) "FDA" means the federal Food and Drug Administration. (l) "Gross Margin Per Tablet" means the Gross Margin calculated in accordance with GAAP and which excludes those non-recurring and unusual items that the Parties agree are not resulting from activities under this Agreement ("GM Adjustment Items") divided by the actual number of MOXATAG tablets (as report by IMS Health Rx data) during the applicable Promotional Period. By way of example, these GM Adjustment Items where appropriate may include inventory write-offs, changes to prior period reserve balances or foreign exchange gains or losses. MBRK agrees to provide a summary of any GM Adjustment Items to DD. The calculation of Gross Margin Per Tablet will be based on U.S. sales of MOXATAG only. For periods after September 30, 2010, if the Gross Margin per Tablet is less than $3.50, the Parties agree to re-evaluate the viability of the Agreement and if deemed necessary will use commercially reasonable efforts to re-negotiate an amendment to the Agreement. (m) "Gross Margin Per TRx" means the Gross Margin per MOXATAG Rx as calculated in accordance with GAAP and which exclude GM Adjustment Items. The calculation of Gross Margin Per TRx will be based on U.S. sales of MOXATAG only. For the period from the Effective Date through September 30, 2010, the Gross Margin per TRx shall be $36.50. (n) "Intellectual Property Rights" means any and all patents, copyrights, trade secrets, trademarks, and any and all other intellectual property rights or interests. (o) "Medical Professionals" means licensed nurses, nurse practitioners, and physician assistants. (p) "MOXATAG" means the prescription drug known as MOXATAG® (amoxicillin extended-release) Tablets 775 mg, approved by the FDA, having NDC numbers 110442-142-03 and 110442-142-02 which is marketed in the US, including currently and subsequently approved formulations, strengths, concentrations and delivery mechanisms. (q) "MOXATAG Labeling" shall mean (a) the FDA-approved full prescribing information for MOXATAG, including any required patient information, and (b) all labels and other written, printed or graphic matter upon any container, wrapper or any package insert or outsert utilized with or for MOXATAG. (r) "Parties" means DD and MBRK collectively. (s) "Prescriber Data" means the prescriber data supplied by a nationally recognized prescription data provider where permitted under federal and state law, which is currently provided to MBRK by IMS Health. (t) "Promotion Commencement Date" means the first day of the month in which DD commences its promotion of MOXATAG under this Agreement. (u) "Promotion Fees" means the Promotion Fees payable to DD by MBRK for the promotion services provided under this Agreement as is calculated by and stipulated in Section 5, which represent fair market value for such services. (v) "Promotional Materials" shall mean all MBRK-approved and available sales representative training materials and all MBRK-approved and available written, printed, graphic, electronic, audio or video matter, including, but not limited to, journal advertisements, sales aids, formulary binders, reprints, direct mail, direct-to-consumer advertising, Internet postings, broadcast advertisements and sales reminder aids (for example, scratch pads, pens and other such items), in each case created by a party or on its behalf and used or intended for use by DD and MBRK in connection with any promotion of MOXATAG hereunder, or disease state or indication for which MOXATAG is approved for treatment but excluding MOXATAG Labeling. (w) "Promotional Measurement Period" means that month during which prescription activity for MOXATAG is measured. (x) "Territory" shall mean the US, including all US territories, possessions and protectorates. (y) "Up-Front Payment" means the one-time payment of $50,000 to be made by MBRK to DD upon execution of this Agreement. Section 2 — Term This Agreement shall commence as of the Effective Date and shall continue in full force and effect for an initial term of three (3) years from the Promotion Commencement Date, divided into three one-year periods. Unless terminated in accordance with the provisions of Section 18, this Agreement shall automatically renew for each subsequent one-year term. Section 3 — Obligations of DD 3.1 DD will promote MOXATAG to DD Target Segment Prescribers using its full suite of promotion solutions where DD and MBRK deem appropriate, including but not
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Extract the exact clause related to "Expiration Date" from the excerpt above.

assistant: This Agreement shall commence as of the Effective Date and shall continue in full force and effect for an initial term of three (3) years from the Promotion Commencement Date, divided into three one-year periods.