Robyn, who has filed for divorce from the Braveheart star, citing "irreconcilable differences", owns millions of dollars worth of real estate in California alone.
She owns at least 11 properties around Malibu in which she has an interest via her private trust, reports The Herald Sun.
With a market value of 24.8 million dollars they range from suburban homes to hilltop estates and were bought between 2001-07.
In Agoura Hills, home to Gibson's Holy Family Chapel, Robyn owns an eight-bedroom Italianate mansion and a 3.4 million-dollar home with five bedrooms, along with a 1.2 million-dollar two-bedroom retreat.
She also owns a 7.3 million-dollar beachfront home and a six-bedroom 1.9 million dollar Santa Clarita ranch.
Robyn is also said to have bought more homes in 2007-8, one of which was said to be worth more than 4.2 million dollars.
According to the Californian law, gifts acquired before marriage and after separation are considered individual property.
Californian divorce lawyer Evan Sussman said Robyn could claim outright ownership of the real estate if she could prove they had been gifts from Gibson.
In the divorce papers, Gibson said they had separated in August 2006 but Robyn did not give a date. (ANI)