One climate-change related threat insurers sayis worth watching—and losing some sleep about: Class-action suitsagainst carbon-based energy companies, accusing them of causingglobal warming and therefore being liable for the resultingdamages.

Perhaps the most famous court case on this issue is Kivalina vs.ExxonMobil, et. al., which pitted a small Alaskan fishing villagewith 390 residents against two dozen of the country’s largest oiland gas companies.

The plaintiffs, who filed suit in 2008, sought up to $400million in damages, based on the federal common law of publicnuisance. They argued that the carbon emitted by the defendantscaused the melting of the sea ice that historically had protectedthe village against fall and winter waves.

The case was dismissed by a U.S. district court, and asubsequent appeal was denied by the Ninth Circuit.

But insurers expect many more of these massive tort claims to befiled—and to seek recovery under Commercial General Liability,Directors & Officers coverage and Professional Liabilitypolicies.