A rare copy of the Magna Carta, the document that enshrined civil rights in English law, is to be sold in New York.
The copy of the Magna Carta is the only one in private ownership
The copy owned by the Perot Foundation is expected to fetch more than $20m (£9.94m), auctioner Sotheby's says.
The copy on sale, sealed by King Edward I and dating from 1297, is the only one in private ownership. King John sealed the original Magna Carta in 1215.
The 1297 manuscript, bought by H Ross Perot in 1984, is due to be auctioned in December.
It was on view until recently in the National Archives in Washington.
The Magna Carta came into being as the result of a dispute between King John and English barons, and it went some way towards limiting the authority of the king.
The charter guaranteed basic freedoms and property rights to those considered "free men".
Its most notable legacy in present-day English law is the principle of Habeas Corpus, which protects people against unlawful imprisonment.
Only four copies dating to the 1215 signing of the Magna Carta are believed to have survived, and all of them are in England.