The 1976 movie Rocky and subsequent sequels made Sylvester Stallone a box-office knockout.

But few know that the actor, now 73, lost the fight in one area - he does not have an equity stake in the lucrative franchise, including the Creed and Creed II spin-offs.

In an interview with trade publication Variety, Stallone said: "I have zero ownership of Rocky. It was shocking that it (ownership) never came to be, but I was told: 'Hey, you got paid, so what are you complaining about?'"

While he added that business naivety led to his lopsided deal with the studio, pundits believe that the actor had no bargaining punch since he was an unknown then.

Still, they are certain that Stallone has not done badly from the franchise, with profit participation from the movies and merchandising deals.

Stallone acknowledges that the legacy of Rocky is something no one can take away from him.

"It's the only voice that I can say what I want without being ridiculed, or being silly, or being precious or sentimental, because he is that way. Rocky can't keep quiet.

"But he's actually saying something, and because of the way he speaks and his (innocence) and gentle quality, you listen.

"Rocky can say things that my other characters can never say."