Mel Gibson and wife Robyn Mel Gibson and wife Robyn

Mel Gibson's divorce could result in the biggest divorce settlement in celebrity history.

There's no indication that Gibson and his estranged wife of nearly 29 years, Robyn, had a prenuptial agreement — which could entitle her to half of everything the actor-director earned during ther marriage, according to People. Gibson's estimated fortune is close to $1 billion.

"This could easily be one of the biggest divorce settlements in Hollywood history," Los Angeles family lawyer Lynn Soodik — who isn't involved in the case — told the magazine. "Any attorney would advise her to take half."

Robyn Gibson's half would tower over other settlements, including the $168 million paid by Michael Jordan in 2006 or the $150 million Neil Diamond lost in 1994.

Gibson's assets include more than $600 million grossed by The Passion of the Christ, $100 million in global real estate investments, and $75 million from projects he has executive produced. Gibson could also have to pay half of every residual check he earns from past projects in the future.

Though big money is involved, Soodik says it isn't likely the divorce will be dragged out in court. "This divorce will probably reach a settlement in a matter of months," Soodik said. "It likely won't be messy since there's enough money to go around."