What is largest combat sport promotions in the world?

1. Ultimate Fighting Championship (UFC): Founded in 1993, the UFC is currently the largest and most popular mixed martial arts (MMA) promotion in the world. It has a roster of some of the best and most skilled fighters in the sport, and holds events all over the world.

2. Bellator MMA: Established in 2008, Bellator MMA is another major MMA promotion that has gained a significant following in recent years. It features top fighters competing in various weight classes, and is known for its exciting matchups and events.

3. Professional Fighters League (PFL): Formerly known as World Series of Fighting, the PFL is a relatively new MMA promotion that has quickly gained popularity. It features a unique format with regular season and playoff events leading up to a championship finale.

4. ONE Championship: Based in Asia, ONE Championship is one of the biggest MMA promotions in the region. It showcases fighters from all over the world, and has a strong focus on promoting respect, integrity, and martial arts values.

5. Glory Kickboxing: Glory is the world's premier kickboxing promotion, featuring top fighters from around the globe competing in exciting matches. It has a large fan base and holds events in various countries.

These combat sport promotions represent some of the largest and most well-known organizations in the world, bringing together talented fighters and providing fans with thrilling matchups and entertainment.