What Apple is actually offering is a fixed royalty payment which is indeed lower.

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As on Houston InterWeb Design's AMP3.com MP3 Web site (see link below) the musicians will receive a fixed royalty for every download of their music as well as a split of the advertising revenue on the site.

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The drilling companies typically acquire leases with landholders who have access to oil and mineral rights below their land by using a landman (either an employee of the company or an independent agent), who offers a fixed price per acre for the right to drill, plus a royalty percentage of the value of the produced hydrocarbons.

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