Undisputed champion he was still described as "undisputed champion" by some reports. After Joe Calzaghe's super middleweight victory over Mikkel Kessler in November 2007, he was frequently described as "undisputed champion". Others disputed this, because although he held the WBA, WBC, and WBO belts, he vacated his IBF title in November 2006 rather than face a mandatory challenger, and immediately vacated other titles as well. The unified champion is defined as a boxer that holds at least two world championships of major sanctioning bodies (WBA, WBC, WBO or IBF) in their respective division. Around 2004, the World Boxing Association recognized three different
Weight class (boxing) Weight class (boxing) A weight class is a measurement weight range for boxers. The lower limit of a weight class is equal to the upper weight limit of the class below it. The top class, with no upper limit, is called heavyweight in professional boxing and super heavyweight in amateur boxing. A boxing match is usually scheduled for a fixed weight class, and each boxer's weight must not exceed the upper limit. Although professional boxers may fight above their weight class, an amateur boxer's weight must not fall below the lower limit. A nonstandard weight limit is called a catchweight.