>Defining climate change as a "health risk" is insane, sorry. If we go down that road, any policy someone doesn't like could be defined as a "health risk" by a sufficiently creative and unscrupulous debater.

Exxon isn't being sued because oil is a health risk. Exxon is being sued because the argument is that they new it was a health risk, and took deliberate steps to hide that information from the shareholders and the public. Just like when car companies get sued for hiding information about safety problems, they are getting sued for hiding the information, not because people get hurt in car accidents.