Ali was stripped of the WBA title in September 1964, after agreeing to an immediate rematch with Liston, which was against the body's rules at the time.
Ali reunited the belts by beating WBA champion Ernie Terrell on February 6, 1967. He was stripped of the WBA belt on April 28, 1967 for refusing induction into the United States army, but retained recognition by the WBC until February 16, 1970.
On February 16, 1970, Frazier defeated Jimmy Ellis for Ellis' WBA belt and the vacant WBC belt. Frazier gained universal recognition by defeating Ali on March 8, 1971.
Mike Tyson became the Undisputed Heavyweight Champion by unifying his WBA and WBC, with Tony Tucker's IBF belt. The Ring Magazine later recognized him as champion on June 27, 1988.
Lennox Lewis became undisputed champion by defeating Evander Holyfield, successfully unifiying his WBC belt with Holyfield's WBA and IBF belts. With that victory, he was also awarded the vacant IBO title. Lewis was stripped of his WBA belt due to a contract dispute regarding a clause in the 2nd Holyfield contract which stipulated he must fight the WBA number 1 contender next. The number 1 contender at that time was Henry Akinwande but he was ill so John Ruiz was later moved up to number 1. The WBA gave Lewis permission under these circumstances to fight WBC ranked contender Michael Grant next as long as he agreed to fight Ruiz in the following bout. Lewis agreed but Ruiz's promoter challenged the WBA's decision in court.
Evander Holyfield became the first undisputed Cruiserweight Champion by defeating Carlos De León, to unify his WBA and IBF belts with De Leon's WBC belt. He relinquished all the belts after moving up to the Heavyweight division. The Ring Magazine stopped recognizing the weight class in 1987.
O'Neil Bell unifies his IBF belt with Jean Marc Mormeck's WBA and WBC belt to become the second undisputed champion of the division's history. He was later stripped for not agreeing to fight the IBF's #1 challenger Steve Cunningham.
Michael Spinks unified the title by defeating Dwight Muhammad Qawi. He later added the IBF title to his undisputed recognition. He vacated all of the belts after moving to the heavyweight division.
Roy Jones Jr. unified the title after defeating Reggie Johnson for his IBF belt, successfully unifying his WBA and WBC belts. Jones relinquished his titles after he moved to the heavyweight division.
Hagler was recognized as the inaugural IBF champion, adding the belt to his undisputed status. He lost the IBF and WBA belt recognitions after deciding to fight Sugar Ray Leonard. He lost the WBC belt after losing to Leonard.
Bernard Hopkins became the undisputed champion after defeating Félix Trinidad in a Middleweight tournament to successfully unify the WBC WBA and IBF belts. He later added the WBO to his undisputed status after defeating Oscar De La Hoya, becoming the first man to ever hold all four titles simultaneously.
Taylor lost his IBF belt for taking a rematch against Hopkins instead of fighting the IBF #1 challenger Arthur Abraham. He officially lost his undisputed status after being stripped of his WBA belt on December 14, 2006
Winky Wright became the first undisputed champion of the light middleweight division after unifying his IBF belt with Sugar Shane Mosley's WBA and WBC belts. Wright lost the IBF belt for taking a rematch against Mosley.
Sugar Ray Leonard unified his WBC with Thomas Hearns's WBA to become the first undisputed champ in seven years. Leonard later relinquished the title after retiring from boxing because of a detached retina.
December 6, 1985
September 27, 1986
Donald Curry
WBA, WBC & IBF
Donald Curry unified his WBA and IBF titles with Milton McCrory's WBC title to become the next undisputed champ.
Judah lost his undisputed championship to Carlos Baldomir, but despite being recognized as the "true" welterweight champion, Baldomir did not pay the sanctioning fees for the WBA or IBF. Consequently, the WBA relinquished Judah as its champion, while the IBF continued to recognise him. Judah later lost the IBF title to Floyd Mayweather Jr.
Kostya Tszyu became the undisputed Junior Welterweight champ after defeating Zab Judah to successfully unify his WBA and WBC belt with Judah's IBF belt. Tszyu was stripped of the WBA and WBC titles because of extended inactivity due to training injuries and lost his IBF belt to Ricky Hatton.
Duran, the WBA champion, won the undisputed title after defeating WBC Champion Estaban De Jesus. Duran gave up the titles after moving up to the welterweight division.
Whitaker, the unified IBF and WBC champion, won Juan Nazario's WBA belt becoming the undisputed champ . Whitaker relinquished all of the belts after moving to the junior welterweight division.
Watanabe had his WBA title stripped for unifying the Super Flyweight championship with the WBC champion Payao Poontarat. He was regarded as the undisputed champion until his loss to Gilberto Roman.
Villa died shortly after this bout. The Flyweight World Title became vacant with the death of its reigning champion--Pancho Villa. The next day William Muldoon of the NYSAC proclaimed Frankie Genaro Pancho's "legitimate successor." But it was Fidel LaBarba who would become the next Undisputed Flyweight Champion of the World.
Jack Dempsey
Max Schmeling
Nino Benvenuti
Carlos Monzón
Vicente Saldivar
