BoxRec

I was looking at montell griffin recorded saw that he fought in 12 different types of title fights in the same division, at light heavy these were-
WBC
IBF
WBO
WBU
IBC
NABF
USBA
IBF inter continental
WBC continental Americas
IBA continental
WBC Asian boxing council
WBO Asian pacific
That's quite a lot but I bet theres others with a lot more, so if you can be arsed have a trawl and post your results

Replying to my own post but anyway, its been harder than I thought but I've gone 1 better and found a 13.
Demarcus Corley all at light welter

WBC
WBO
Interim WBA
USBA
NABF
WBC continental americas
WBC Asian boxing council
WBC international silver
WBC Mediterranean
WBC fecarbox
Interim WBC Latino
WBO European
WBO intercontinental

Not a winner but thought Joe bugner was in some interesting title fights
Joe bugner

WBC
WBA
WBF
British
European
Commonwealth
Australian
WBO inter continental
PABA