Tesoro's (TSO +6%
) $2.5B purchase
's Carson oil refinery goes against the prevailing wisdom
that says California is a lousy place to be a refiner because of the state’s environmental regulations. The deal brings the number of TSO's California refineries to three and lifts its operations in the state to 60% of its total. TSO says the deal leaves it "well positioned to generate significant operational efficiencies."