"Anything short of, 'We are giving a product, we are giving cash, over and out, ' gets into a gray area, " says marketing consultant Jim Stengel.

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The company also has marketing deals with UFC's Gray Maynard and Strikeforce's Jay Hieron.

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Chris Gray, 23, a business graduate, moved back from England to his native Derry to open his own marketing company, Admann.

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