French bank BNP Paribas (BNPP.PA), which is facing a potential $10 billion fine for breaking U.S. sanctions, has handed over to U.S. investigators files covering many years of its dealings with leading companies in the oil market. A dozen former BNP insiders and senior trading executives said it had in recent months handed over a host of documents relating to its oil dealings with Sudan and Iran, including details on trading houses’ and oil majors’ involvement in the trades. Before now, all that had been known about the probe was that U.S.