By CompuBox
MOST CONSECUTIVE HEAVYWEIGHT TITLE DEFENSES
2. Larry Holmes -- 19 (20 if you include the Marvis Frazier fight, which was unsanctioned by the IBF)
3. Wladimir Klitschko -- 15 (has 20 defenses in two title reigns)
4. Tommy Burns -- 11
5. Muhammad Ali -- 10 (has 19 total defenses in three reigns)
6 (tie). Vitali Klitschko -- 9 (has 12 defenses in three reigns)
6. (tie) Lennox Lewis -- 9 (has 14 defenses in three reigns)
6. (tie) Mike Tyson -- 9
6. (tie) Joe Frazier -- 9 (if one counts four NYSAC title defenses)
* As of April 26, 2014