And if someone thinks this is a virtual threat, google for "Philip Morris vs. (Australia|Uruguay)" (countries being sued for anti-tobacco regulations hurting business of PM)
Unfortunately, that doesn't seem to be entirely clear. The case you refer to in Australia was apparently thrown out because of some dubious changes to the company ownership arrangements that appeared to have been made just for the purposes of bringing a lawsuit, when the change in cigarette packaging rules was already public knowledge by that time.
http://theconversation.com/big-tobacco-vs-australia-philip-m...
Yes, it's a virtual threat.