For years, Exxon Mobil condemned climate change campaigners. The oil giant went so far as to fund researchers and think tanks to spread the message that global warming was just a load of hot air, according to a report from the Union of Concerned Scientists.

Not dissimilar to the the tobacco industry campaign of disinformation intended to mislead the public about the health risks of smoking.

Now we're told it's changing and the oil giant might be turning green. That seems to be the suggestion in this piece from Fortune writer Marc Gunther.

The company has been talking to environmentalists, religious investors, and socially responsible mutual funds. It's even stopped funding the anti-global warming crusaders at the Competitive Enterprise Institute.

The question is what's driving the change? And how real is it?

As The Wall Street Journal points out, available here via the Pittsburgh Post-Gazette, the apparent shift is highly nuanced. Exxon Mobil still notes uncertainties in climate science, it still opposes the Kyoto Protocol and it also stresses that any future carbon policy should include developing countries, where emissions are rising fastest. Beneath the apparent changes, the substance is still the same.

Certainly, Exxon Mobil chairman and chief executive Rex Tillerson says the company has a PR problem on global warming and has told a select group of Wall Street fund managers and analysts that it won't be changing its position on global warming, it would just try to explain it better. For the full report, check The Guardian..

And last week at Davos, Tillerson told delegates that world energy consumption will rise more than 50 per cent until 2030, that 80 percent of world energy consumption will come from fossil fuels, such as oil, gas and coal and that Exxon Mobil was ready to provide it. You can read the report in Forbes.

So what sort of change is it? The answer is simple: Exxon Mobil is being totally pragmatic. As the WSJ piece suggests, the company can smell the changes in the political climate and it wants to negotiate the potential structure of US carbon regulation, if and when it happens:

"The economic reality is that some companies will win from a carbon constraint and some companies will lose, depending on how the regulation is written. One question is whether a carbon tax or cap should be imposed upstream - on producers of fossil fuels - or downstream, on the industries, and perhaps even the individual consumers, who use those fuels. Another question is whether such a constraint should target just a few industries or should be applied across the economy."

Guess which position Exxon Mobil will take?