The U.S.-based Annenberg Foundation purchased 21 sacred Hopi masks at an auction in Paris on Monday, December 9. The Foundation acquired the works, which are worn by dancers during religious ceremonies and considered to be living beings, solely for the purpose of returning them to their rightful owner.

A number of groups, including the U.S. embassy, had attempted to block Monday’s sale. Advocacy group Survival International challenged the auction in court on behalf of the Hopi tribe, but the case was dismissed by a judge who ruled the sale legal in France. The sale of sacred Indian artifacts has been outlawed in the U.S. since 1990 but the law does not extend to overseas transactions. Gregory Annenberg Weingarten, director of the California-based foundation, decided to buy the masks after Survival International’s lawsuit failed.

The Annenberg Foundation helps fund non-profit organizations across the world.