Brazil's largest oil workers union filed a lawsuit against U.S. oil company Chevron and drilling firm Transocean that seeks to cancel their rights to operate in the country as the result of an offshore oil spill last November. The case, brought by the FUP oil workers federation in Brazilian federal court, raises the legal and political stakes for Chevron and Transocean which are already fighting criminal and civil cases related to the spill. FUP, which has long opposed foreign involvement in Brazilian oil development, said Chevron and Transocean "offended the Brazilian people" with "predatory and environmentally unsound practices."...Kurt Glaubitz, Chevron's spokesman...and Transocean spokesman Guy Cantwell in Houston had no immediate comment on the suit. Both have said the previous charges against the companies and their employees are without merit. [also refers BP, Petrobras]