Mel Gibson Mel Gibson

Mel Gibson's wife of nearly three decades has filed for divorce, citing irreconcilable differences.

"Throughout our marriage and separation we have always strived to maintain the privacy and integrity of our family and will continue to do so," the couple said in a statement Monday.

TMZ, which first reported the filing Monday, says Robyn and Mel Gibson had no prenuptial agreement. Under California law, communal property, including earnings, is divided in half. Gibson's fortune was estimated at $900 million in 2006.

The Lethal Weapon star, who won two Oscars for Braveheart, has kept a much lower profile since unleashing an anti-Semitic tirade during a 2006 arrest on suspicion of driving under the influence. He later pleaded no contest.

He turned up on the post-Oscar episode of Jimmy Kimmel Live earlier this year, sporting an old-timey mustache-goatee combo. On the show, he denied one of the stranger accounts in the police report of his arrest: that he called a female officer "sugar tits."

The Gibsons have seven children, just one of whom, Tom, is a minor. Robyn Gibson is seeking custody.

The couple married in June 1980, and Robyn Gibson lists the date of their separation as "TBD."

Her attorney, Laura Wasser, who has also handled the divorces of Britney Spears, Angelina Jolie, and Stevie Wonder, did not return a call for comment Monday.

Get more details Monday at 9 pm/ET on the TV Guide Network's Hollywood 411.