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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pass to ALFA AESAR upon shipment from NTC's dock in compliance with United States D.O.T. requirements and all applicable laws and regulations. 4.3 NTC shall invoice ALFA AESAR for payment of Products delivered to ALFA AESAR on a Net 30 day basis. Excepting any amounts disputed in good faith, balances unpaid after such period will be subject to a finance charge of 1% per month or may be offset against any balances owed by NTC to ALFA AESAR. The parties agree to work in good faith to resolve any disputed invoice. In the event such efforts do not resolve the dispute within sixty (60) days, either party may initiate Arbitration proceedings pursuant to Section 16. 5. Returns; Discontinued Products. 5.1 Return Rights. Subject to the protocol described below, ALFA AESAR shall have the right to return at NTC's expense, and for full credit of ALFA AESAR's cost, any Products (i.) for which a legitimate and credible allegation is made that the use of such Products infringes on any patent, trademark, trade secret, copyright, right of privacy or publicity, or any other tangible or 3 intangible proprietary or intellectual property right; (b) that are not manufactured, packaged, or labeled in accordance with specifications or industry standards; (c) that are shipped in error or in non-conformance with ALFA AESAR's purchase order; or (d) that are damaged or defective. In the event that ALFA AESAR believes that it is entitled to return any Products delivered under this Agreement, the parties will adhere to the following protocol: (w) ALFA AESAR will contact NTC's Quality Director and then forward to the Quality Director, via a carrier selected by and at NTC's expense, a sample of the Product that ALFA AESAR believes is non-conforming; (x) upon receipt of the sample, NTC will test it and then notify ALFA AESAR of the test results; (y) where the test results confirm that the sample is non-conforming, NTC will provide ALFA AESAR with NTC's Return Authorization Number ("RAN"); and (z) any returned non-conforming Product must be in its original container, with original labels in act, and all paperwork concerning the returned Product must include NTC's RAN. 5.2 NTC may discontinue offering any Product for any reason by providing six (6) months advance written notice to ALFA AESAR, provided however, NTC shall continue supplying ALFA AESAR with such discontinued Product until the expiration of such six (6) month notice period. Notwithstanding the foregoing, NTC may discontinue any Product immediately upon written notice to ALFA AESAR if such discontinuation is due to any actual or alleged Product defect which may actually or allegedly cause damage to person, property rights or property, With respect to ALFA AESAR's existing inventory of discontinued Product, ALFA AESAR may, its sole discretion, return such Product at any time to NTC for full credit or refund. 6. ALFA AESAR Referrals. 6.1 The following shall be deemed referral sales for which NTC shall pay a commission in accordance with Section 6.2. a. ALFA AESAR shall refer to NTC the following sales requests either directly or by navigation on ALFA AESAR's Web site: i) any sales for single Product orders in excess of Research Quantities; or ii) any sales inquiries for Custom Services. 6.2 NTC shall pay ALFA AESAR a commission for all sales under Section 6.1 as follows. The terms of this Section 6.2 shall survive any expiration or termination of this Agreement. a) For all referrals under Section 6.1, except where NTC has evidence that it referral the customer (including its affiliates) to ALFA AESAR to purchase a prior sample of the Product in question, or where NTC has made sales to the customer (including its affiliates) referred to NTC by ALFA AESAR within a period of twelve (12) months before ALFA AESAR's referral under Section 6.1, NTC shall pay ALFA AESAR a commission at the rate of [***] on the Net Sales made to each such customer so referred to NTC under Section 6.1. NTC shall pay ALFA AESAR on a monthly basis for all such commissions for a period of three (3) years from the date of such referred customer's first order of Products or Custom Services from NTC. *** CONFIDENTIAL TREATMENT REQUESTED—This confidential portion has been omitted from this document and filed separately with the Commission. 4 6.3 NTC shall maintain adequate records of its invoices and accounting records reflecting all such sales in accordance with standard accounting principles. Within twelve (12) months after the date this Agreement has been terminated by the parties,
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Extract the exact clause related to "Revenue/Profit Sharing" from the excerpt above.

assistant: For all referrals under Section 6.1, except where NTC has evidence that it referral the customer (including its affiliates) to ALFA AESAR to purchase a prior sample of the Product in question, or where NTC has made sales to the customer (including its affiliates) referred to NTC by ALFA AESAR within a period of twelve (12) months before ALFA AESAR's referral under Section 6.1, NTC shall pay ALFA AESAR a commission at the rate of [***] on the Net Sales made to each such customer so referred to NTC under Section 6.