Anyone Remember Whether DeBeers Was Well-Known in 1981? Rapaport News reports that "De Beers to Defend Trademark in NYC." From the article: "[The Defendant] Rosenblatt incorporated DeBeers Diamond Syndicate in the state of Delaware September 10, 1981. In December 2001 he registered nearly three dozen domain names, and filed (as a trademark) in January 2002 the words: DeBeers Diamond Syndicate."