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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SUPPLY 4.1 ETON shall enter into a commercial supply agreement with a contract manufacturing organization and Aucta shall enter into a commercial supply agreement with an active pharmaceutical ingredient supplier within ninety (90) days from the Execution Date unless otherwise agreed to by the parties in writing. 4.2 If the terms of Aucta's commercial supply agreement with the active pharmaceutical ingredient supplier in Section 4.1 is assignable to ETON, ETON may assume the aforementioned agreement by providing written notice to Aucta, and Aucta will have seven (7) days from receipt of the notice to assign the aforementioned agreement to ETON. 6 Source: ETON PHARMACEUTICALS, INC., 10-Q, 11/14/2019 CONFIDENTIAL 5. SALES, MARKETING AND DISTRIBUTION 5.1 ETON shall be solely responsible for the Marketing of the Products and shall have sole and exclusive right to make all Marketing decisions for the Product in the Territory, including without limitation to pricing, contracting, sub-licensing, co-promoting, or any contract promotion activities. 5.2 ETON shall use commercially reasonable efforts to Market the Products in the Territory during the Term of this Agreement. 5.3 ETON shall have the sole and exclusive right to determine all terms and conditions of sale of the Products to its or its prospective consumers. 5.4 [ * * * ] 6. MILESTONES AND OTHER PAYMENTS 6.1 Licensing Fees. ETON shall pay to Aucta licensing fees of up to an amount of five million dollars ($5,000,000) based on the following payment schedule: (a) An amount of two million dollars ($2,000,000) within five (5) days of the Effective Date of this Agreement. (b) An amount of two million dollars ($2,000,000) within thirty (30) days after the first commercial sales of Product. [ * * * ] (c) An amount of one million dollars ($1,000,000) within thirty (30) days after the issuance and listing of a patent in the Orange Book for the Product and its Dossier, only if that patent is listed prior to the submission of an ANDA referencing the Product and its Dossier as the reference product. 6.2 Commercial Milestones. ETON shall pay to Aucta a total sum amount of up to eighteen million dollars ($18,000,000) based on Net Sales of a Product (on a Product by Product basis) after the achievement of the following one-time milestones for each Product: (a) An amount of one million dollars ($1,000,000) upon Net Sales first exceeding an amount of ten million dollars ($10,000,000) in a calendar year to be paid within sixty (60) days after the calendar year end. (b) An amount of two million dollars ($2,000,000) upon Net Sales first exceeding an amount of twenty million dollars ($20,000,000) in a calendar year to be paid within sixty (60) days after the calendar year end. (c) An amount of five million dollars ($5,000,000) upon Net Sales first exceeding an amount of fifty million dollars ($50,000,000) in a calendar year to be paid within sixty (60) days after the calendar year end. 7 Source: ETON PHARMACEUTICALS, INC., 10-Q, 11/14/2019 CONFIDENTIAL (d) An amount of ten million dollars ($10,000,000) upon Net Sales first exceeding an amount of one hundred million dollars ($100,000,000) in a calendar year to be paid within sixty (60) days after the calendar year end. 6.3 Royalty. 6.3.1 ETON shall pay to Aucta a royalty payment of [ * * * ] of Net Sales of the Products. 6.3.2 [ * * * ] 6.3.3 If the amount of royalty payment under Section 6.3.1 is less than the amount of royalty payment under Section 6.3.2, then ETON shall pay Aucta the difference between royalty payments in Sections 6.3.1 and 6.3.2 within sixty (60) days of the calendar year end, but in no event shall the difference paid be greater than the minimum amount in Section 6.3.2. 6.3.4 For payments under Section 6.3, ETON shall pay Aucta royalty payments under Section 6.3.1 or 6.3.2 only, but not under both sections concurrently. 6.3.5 If ETON is unable or limited in its ability to sell the Products due to supply chain (e.g., manufacturing, API, etc.) or regulatory issues, that extend for a period of thirty (30) days or more, the minimum royalty payment under Section 6.3.2 shall be adjusted to prorate the annual minimum to account for the period of inability to supply; provided, however, that the minimum royalty payment shall be paid if the inability or limitation of sales by ETON is directly and solely due to ETON's gross negligence or willful misconduct. 6.3.6 [ * * * ] 6.3.7 Within thirty (30) days following the
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Extract the exact clause related to "Revenue/Profit Sharing" from the excerpt above.

assistant: ETON shall pay to Aucta a royalty payment of [ * * * ] of Net Sales of the Products.