A Hebrew Bible that’s more than 1,000 years old could sell for up to $50 million at auction this spring, which would make it the most valuable historical document ever auctioned.

Sotheby’s in May will auction off the so-called Codex Sassoon, which dates to the ninth century and bridges the discovery of the Dead Sea Scrolls and the modernly accepted form of today’s Hebrew Bible.

“It is a vital touchstone of human history,” said Richard Austin, Sotheby’s global head of books and manuscripts.

The sales estimate for the Bible is between $30 million to $50 million. In 2021, hedge fund billionaire Ken Griffin paid $43.2 million for a first edition copy of the U.S. Constitution at a Sotheby’s auction. In 1994 Bill Gates paid $30.8 million for the Codex Leicester, a collection of scientific writings that contains drawings by Leonardo da Vinci.

The name “Codex Sassoon” comes from the Bible’s previous ownership, as part of the famed collection of David Solomon Sassoon, who assembled the most significant private collection of Judaica and Hebraica manuscripts in the 20th century. Before the Codex Sassoon, only fragments of biblical texts existed in scroll form, experts say.

Sotheby’s said that while the Bible held a prominent place in Sassoon’s collection, it was only recently only recently scientifically studied and carbon dated by the current owner, whom Sotheby’s declined to name.

The carbon dating verified its dating to the 9th century, making it older than the Aleppo Codex and Leningrad Codex, two other well-known early Hebrew Bibles.