An annotated edition of Harry Potter And The Philosopher's Stone has become the most expensive J.K. Rowling book ever sold after raising $227,421 at auction.

The unique first edition, which featured notes from Rowling throughout, was the star attraction at the First Editions, Second Thoughts sale at Sotheby's in London on Tuesday (21May13).

The novel was at the centre of a bidding war and finally sold to an unidentified phone buyer for $227,421, the most ever paid for a printed book by Rowling.

Other auction highlights included a copy of Roald Dahl's Matilda, which boasts illustrations by Quentin Blake, which sold for $46,500, while an edition of Kazuo Ishiguro's The Remains of the Day went under the hammer for $27,900.

The total amount pulled in at the event, which benefits charity organisation English PEN, was $680,000.