Bantamweight is a weight class in combat sports. In MMA, the Bantamweight Division is within 126-135 lbs (57.2-61.2 kg). The Bantamweight Division sits between the Flyweight Division (116-125 lbs) and the Featherweight Division.
Prior to UFC-WEC merger, Dominick Cruz was the WEC Bantamweight Champion. At WEC 53, Cruz defeated Scott Jorgensen to retain the WEC Bantamweight Championship and was simultaneously awarded the inaugural UFC Bantamweight Championship.
At UFC 173, T.J. Dillashaw defeated Renan Barao to win the UFC Bantamweight Championship. At UFC Fight Night: Dillashaw vs Cruz, Dominick Cruz became the first-ever two-time Bantamweight Champion. At UFC 207, Cruz lost the title to Cody Garbrandt, who eventually lost it to Dillashaw, making the latter a two-time division champion.
Due to a failed drug test, Dillashaw vacated his title in March 2019. After winning the vacant title at UFC 238 and defending it at UFC 249, Cejudo became the fourth UFC fighter to hold titles in two different weight classes (Flyweight and Bantamweight) simultaneously, and the second to defend titles in two different weight divisions.
Petr Yan defeated Jose Aldo at UFC 251 and became the current UFC Bantamweight Champion.
In his first title defence, Yan faced #1 ranked Bantamweight Aljamain Sterling at UFC 259 on March 6, 2021 and lost the title by disqualification due to an intentional illegal knee landed by him in the fourth round to Sterling.
Sterling couldn't continue the fight any further due to concussion and the doctor recommended to stop the fight thus making him the new UFC Bantamweight champion. This is the first ever title change caused by a disqualification in UFC history.