Nigeria is looking to claim $62 billion from international oil firms for back revenues it says it is owed -- but even the country's own oil minister admits the government has little chance of success. The eye-watering amount relates to a 1993 law governing production sharing agreements between the country and oil majors that said the revenue split should be reviewed if prices reached over $20 per barrel. Despite the price of crude soaring above that point over the past two decades the divi ......