Traditionally there was only one champion per weight division, and it was easy to decide the next champion by beating the current one. With the introduction of numerous sanctioning bodies – each having their own ‘world champion’, it became more complicated.
The term lineal champion is used to denote a ‘true’ champion in a weight division based on their ring contests and is commonly described as “the man who beat the man”. Similar to a line of succession going back to an undisputed champion – these days this is a fighter who holds world titles in all four major sanctioning bodies at the same time.
However, it is not necessary to be an undisputed champion to be a lineal champion, a boxer does not need all the belts. It can be decided by independent ratings and is largely used for kudos or to promote a fight or fighter.
There can be dispute of lineal champions including for inactivity, if a boxer has a long break from boxing. These situations are often settled by the highest ranking contenders fighting each other in order to be considered the new lineal champion. The lineal champion title is also given up and becomes vacant, if a fighter retires or vacates their weight class. Opinion is divided on whether lineage is a useful measure versus the more official title belts and unification bouts.
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