Estimated at $20,000 at the June 9 auction, the anonymous buyer will pay $52,500 including premium (25/20/12% buyer's premium).
It was sold by Justin Schiller, the antiquarian bookseller who in 1985 attempted to broker its sale for $1.5m.
The Oath, a pledge of loyalty and duty demanded of all new members of the Massachusetts Bay Colony, is considered to be the oldest printed document in English North America, produced in Cambridge, Massachusetts, c.1638.
No copy of this diminutive broadsheet was thought to have survived, until 1985 when the Utah documents dealer (and master forger and convicted murderer) Mark Hofmann claimed to have discovered a copy in a New York bookstore.
Hofmann – the subject of a number of books and documentaries including the current Netflix hit Murder Among the Mormons – pleaded guilty to two counts of second-degree murder and is serving a life sentence in the Utah State Prison.
He later confessed to prosecutors that The Oath of a Freeman was an elaborate fabrication involving 17th century paper, printing ink created using a 400-year-old recipe and a manufactured printing plate. He planted it in the shelves of a second-hand bookstore so it could be ‘discovered’ and bought for $25.
The simple x 6in (10 x 15cm) sheet fooled scores of bibliophiles including Schiller, who entered negotiations to sell it to the Library of Congress for $1.5m.
It was turned down not because the Oath was deemed a fake but “because of questions about its price, provenance and title”.