It's very convoluted. You have to open the PDFs in the links near the bottom of their page (under the Downloads section) and read all the footnotes and fine print. Their OEM tire and not-OEM tire warranties are different.I looked into Micheline's warranty. It states a 30K "limited warranty", and offers no description of what "limited" means.
I'll go out on a limb and say that means no warranty. They barely last 20K miles, much less 30K.