Do oil companies tell shareholders the unvarnished truth about the risks posed by climate change to their business models? Climate campaigners have long argued that they don’t, claiming that wicked oil bosses routinely downplay the possibility that government policy changes, rival technologies and carbon taxes might make their businesses unviable.

Oilchange International, a UK based campaigning group, published a document last year outlining what it called oil bosses’ “selective scepticism” towards renewable power and non-hydrocarbon burning cars. Citing the companies’ own documents and forecasts, it said that BP and ExxonMobil estimated costs for renewable energy and electric vehicles that were well above mainstream industry estimates, implying their adoption would be far less widespread, and hydrocarbons consequently more ubiquitous. For instance, BP’s forecast for solar costs in 2050 was higher than the actual average cost in 2016. All of which makes a groundbreaking New York lawsuit that has just been brought against Exxon seem somewhat, well, out of leftfield.

The oil supermajor has been accused of securities fraud by Barbara Underwood, the state’s attorney-general, over some of its climate disclosures. Exxon isn’t accused of bamboozling investors by painting a rosy picture of the prospects for oil and gas while secretly preparing for something much more unfriendly. Quite the reverse. The company actually told investors that its business faced strong headwinds from high “proxy costs” associated with restrictions on future emissions.

Meanwhile, its internal planners used far lower numbers when deciding whether or not to allocate capital to investment projects. Ms Underwood described this as a “façade to deceive investors”. But it’s a pretty rum old fraud. How were those investors being diddled, exactly? By being dissuaded from buying Exxon’s shares, and hence missing out on all the juicy profits the insiders secretly predicted?