Stock in DineEquity Inc. (NYSE:DIN), Brinker International (NYSE:EAT) and Darden Restaurants (NYSE:DRI) all plummeted around the same time.

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"The results included in the CSPI study were significantly higher than our findings, " said Maureen Locus, spokeswoman for Brinker International, the parent company of Chili's and Maggiano's.

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Brands and Brinker International.

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