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 Business Highlights The major oil companies racked up significant gains in net income for the third quarter by charging more for oil than they could a year ago, and making money refining it.

The companies also earned more from producing natural gas, but a couple have signaled that the current low price for gas could force a change in strategy.

Both oil and gas increased in price when compared with the average price from last year. Oil prices rose about 12 percent while natural gas increased 23 percent. As a result, Exxon Mobil Corp. on Thursday reported 55 percent higher profits for the third quarter, while on Wednesday, ConocoPhillips said profit doubled.