Elizabeth Taylor’s estate is suing Christie’s, the auction house, over the $8.8 sale of the “TajMahal” diamond, a gift to the late actress from Richard Burton on her 40th birthday.

The TajMahal diamond was sold by Christie’s along with the rest of Taylor’s jewels and wardrobe in New York following her death in 2011. The collection, which was dubbed the “Crown Jewels of Hollywood,” broke all expectations and brought in $183.5 million to benefit the Elizabeth Taylor AIDS Foundation.

But the trustees of her estate have now filed a complaint alleging breach of contract. They claim the anonymous buyer of the TajMahal diamond returned it months after determining that it actually does not belong to the wife of a 17th century Mughal emperor.

According to the complaint auction house had only stated that the diamond was of Indian origin, but it still agreed to cancel the sale. Christie’s then requested that the estate return the proceeds of the sale.

Christie’s violated its own policies when it rescinded the sale, the trustee’s complaint states. “Despite facing no credible threat of legal liability, Christie’s nonetheless rescinded the sale of the diamond. In doing so, Christie’s not only deviated from its usual business practices and its own established policies, but it violated its obligations to the trust, all in an effort to appease the buyer.”

Taylor’s trustees claimed the auction house also refused to pass on $3 million from the sale of another gem called the Bulgari Ring.They said: “(Christie’s) failed to pay the trust the proceeds from the sale of the Bulgari ring in an attempt to strong arm the trust into returning the proceeds that the trust rightfully received from the sale of the TajMahal diamond.”

In a statement Christie’s said: “Christie’s was pleased to create a landmark auction event on behalf of the Elizabeth Taylor Trust that produced over $183.5 million in proceeds for the beneficiaries of the trust – the friends and family of Elizabeth Taylor.This suit stems from Christie’s seeking the return of a small portion of these proceeds due to the cancellation of a single item from that sale, and Christie’s looks forward to a speedy resolution of this matter.”