Harvard’s law school library paid $27.50 in 1946 to acquire what was billed as a “somewhat rubbed and damp-stained” copy of the Magna Carta from 1327 to add to its robust collection of medieval texts.

Harvard University for decades assumed it had a cheap copy of the Magna Carta in its collection, a stained and faded document it had purchased for less than $30

A “copy” of Magna Carta bought decades ago by Harvard Law School for just $27.50 is now understood to be an extremely rare original from 1300, according to new research.