It simply has to be legal to transfer unused credits from one taxpayer to another.

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In the 13 states that offer transferable film tax credits, a brokerage industry has quietly cropped up that allows unused credits to be sold to unrelated industries.

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At a recent conference, Zerbe noted approvingly, his former boss Grassley, the ranking Republican on the Senate Finance Committee, suggested changes to the AMT, which would allow these old unused credits to be claimed retroactively.

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Donnelley asked for a refund based on carrying back unused research credits and foreign tax credits.

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Turn unused gift cards or store credits into shiny, new ones from popular retailers or restaurants.

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