THE RICHEST WOMAN in Europe, L’Oreal heiress Liliane Bettencourt, has been declared mentally unfit to control her estate and has been placed under the guardianship of family members.

Bettencourt, 88, and her estranged daughter Francoise Bettencourt-Meyers have been involved in a legal battle over the family fortune for some time.

Bettencourt-Meyers claimed that her mother was squandering the family’s wealth on sycophants – publicly accusing celebrity photographer Francois-Marie Banier of abusing her mother’s alleged mental frailty and trust by cheating her out of €1 billion  in cash, artworks and other gifts.

Banier, a longtime friend of Bettencourt’s, has insisted he did not take advantage of her and the case was eventually dropped, however the dispute prompted a string of legal cases.

The court found that the 88-year-old billionaire suffered from “mixed dementia” and “moderately severe” Alzheimer’s disease. Bettencourt-Meyers and grandsons Jean-Victor and Nicolas will now control Bettencourt’s wealth and estate.

Bettencourt’s lawyer has described the ruling as “profoundly disappointing”, reports the BBC. Bettencourt and her legal team intend to appeal the ruling.

Bettencourt’s heirs are reportedly concerned about her health and management of her fortune, estimated at $20 billion by Forbes magazine. She is a major shareholder in cosmetics giant L’Oreal, which was founded by her father Eugene Schueller in 1907.

Meanwhile, an investigation into claims that Bettencourt gave illegal donations to Nicolas Sarkozy during his presidential campaign is ongoing.

Additional reporting by the AP