The letter is signed by a host of high profile artists from across the musical spectrum: Katie Perry, Sheryl Crow, Rihanna, Pink Floyd, Blondie, Bill Joel, Amy Grant, Megadeth, CeeLo Green, Ted Nugent and the Dead Kennedys.

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In the past, film studios have pursued Google, Apple and others over apps that use content from films such as Ted, Spiderman and Green Lantern.

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United won't release specifics, but spokesperson Jeff Green insists that United has made "double-digit market share" gains on routes where Ted competes with low-fare carriers.

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Invited speakers at this year's TED include a voting system designer, a women's rights activist, a green chef and a physicist who runs a lab that aims to allow anyone to make almost anything.

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