Mel Gibson. (WENN)

Mel Gibson will hand over half of his Screen Actors Guild pension benefits to his ex-wife Robyn as part of their divorce settlement, according to legal documents.

The Braveheart star split from his spouse, who he wed in 1980, in 2006 and she filed for legal separation in April 2009, citing "irreconcilable differences" for ending their marriage.

Gibson, whose divorce was finalised in December, handed over an estimated $425 to his ex – and it has now emerged part of his retirement package will also go to his former partner.

Editors at TMZ.com have obtained documents relating to the case and reveal Robyn will receive 50 per cent of the Screen Actors Guild pension benefits Gibson accumulated during their marriage, as well as a "big chunk" of the star's Directors Guild of America pension benefits.

She will also receive half of the benefits Gibson accumulated through their production company Icon during their marriage, according to the website.