NEW YORK, Dec 18 (Reuters) 02:00 - A rare 710-year-old copy of the Magna Carta was sold at auction for $21.3m by The Perot Foundation at Sotheby’s in New York, the auction house said on Tuesday.

The Magna Carta established the rights of the English people and curbed the power of the king. The US constitution includes ideas and phrases taken almost directly from the charter, which rebellious barons forced their oppressive King John to sign in 1215.