A group of European investors, including, Triffin BV of the Netherlands and IFINT Societe Anonyme of Luxembourg, has acquired a 13% stake in Novato, Calif.-based Fireman’s Fund Corp., according to an SEC filing . . . Coast Savings & Loan Assn. of Los Angeles will hold a special stockholders meeting Dec. 15 to ask stockholders to approve the formation of a holding company.