Michelin became MotoGP’s sole tire supplier starting with the 2016 season.
The change followed Bridgestone’s withdrawal from the premier class after serving as the exclusive supplier from 2009 through 2015. Michelin had a long history in Grand Prix motorcycle racing and returned to MotoGP under a single-supplier agreement, meaning every premier-class bike used Michelin tires rather than choosing between competing brands.
Michelin’s return coincided with several technical changes. MotoGP switched from 16.5-inch wheels to 17-inch wheels in 2016, bringing the premier class closer to the wheel size already used in Moto2 and Moto3. Riders and teams therefore had to adapt their setup work, tire management and riding styles to a new package rather than simply continuing with the previous Bridgestone characteristics.
This question concerns MotoGP specifically, not every class in the championship. Dunlop has supplied the intermediate Moto2 and lightweight Moto3 categories, while Pirelli is associated with other major motorcycle championships, especially the production-based World Superbike series. Thus, Michelin is the correct answer for the premier-class sole-supplier arrangement that began in 2016.