By Todd Wallack The Boston Globe November 23, 2012 Dunkin’ Donuts won’t be able to claim exclusive rights to the phrase “Best Coffee in America.” The Patent and Trademark Office has tentatively rejected the Canton-based chain’s efforts to trademark the slogan, saying it is not distinctive enough to qualify for protection. The slogan “is merely laudatory and descriptive,” the agency ruled recently. “Anyone at all can claim that their coffee is the ‘Best Coffee in America,’ ” said a Newton trademark attorney, Zick Rubin. “No one takes such a claim literally, and no one company can monopolize the phrase.” Both Rubin and the trademark office noted the ruling has an obvious precedent. The maker of Sam Adams beer, Boston Beer Co., tried to trademark a similar slogan, “The Best Beer in America.” But the trademark office turned down the request, and an appellate court upheld the decision in 1999. The Boston brewer has continued to use ...