That analysis doesn't take into account how this will really work. Saying you're a company from a country that signed on to the Paris agreement doesn't mean that you won't—in fact, you probably will—use the ISDS provisions to challenge other governments' specific actions that you think are affecting your trade or investment for whatever reason. Being a company from Japan or being a company from the U.S. doesn't mean you can't use ISDS to challenge Canadian government action to fight climate change.
On May 13th, 2016. See this statement in context.