LONDON (AP) — A proof copy of the first Harry Potter novel that was bought for pennies in a second-hand bookshop almost 30 years ago has sold at auction for 11,000 pounds, or $13,900.

British auctioneers Hanson’s said Monday that the first-edition copy of “Harry Potter and the Philosopher’s Stone,” which states “uncorrected proof copy” on the cover, was bought in 1997 from a shop in south London with two other books for a total of 40 pence ($0.50.)

The seller, who was not named, picked up the book about the famous boy wizard as a “throw-in” with other titles and didn’t read it or pay much attention to it for years.

The book was sold to a private U.K. buyer on Wednesday for a hammer price of 11,000 pounds.