The book is a proof copy, published before the first official versions of the Potter novels came out. It says it's by JA, not JK, Rowling.
But that's just added to its value: it was sold at auction for a whopping £1,468 on Monday.
About 100 proof copies of the novel were printed for book industry people.
"Very few proof copies are around which is why the Harry Potter books have a high valuation," said a spokesman for the auctioneers.
"They were published in very small numbers and just circulated within the publishing industry."
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