ExxonMobil is quietly lobbying for the U.S. to adopt a carbon tax, both in Washington circles and at the American Petroleum Institute.

For years a denier of climate change, the company is facing probes in New York and Massachusetts over whether it hid its understanding of a link between climate change and the burning of oil and gas. Exxon also has an eye on coming government initiatives to battle climate change that could be more intrusive than a carbon tax.