9. BJ Penn
Only the second fighter to hold UFC championships in more than one weight class, Penn was a superstar back in the day, despite getting into bar fights these days. Anyway, this is about his welterweight days. After choking out Matt Hughes at UFC 46, Penn signed with K-1 and was abruptly stripped of his belt by the UFC.
They said that he was refusing to defend his title by signing a professional contract with another promotion – despite it being a different sport. Penn filed a lawsuit to prevent them from making a new champion but lost. The promotion and fighter would eventually mend their broken bridges.
