The sixth book in the Harry Potter series - the fastestselling book of all time - has also become among the quickest to fall prey to internet piracy, with illicit copies available online within hours of its release.
Tech-savvy fans of the boy wizard teamed up to scan the entire 607 page book into digital form, with unauthorised e-book copies appearing online less than 12 hours after Harry Potter and the Half-Blood Prince went on sale on Saturday.
Copies of the audio version of the book were also widespread on file-trading networks such as BitTorrent.
A lawyer for author J.K. Rowling's agents, Christopher Little, said his firm was working to combat the piracy but admitted that some illicit copies would probably slip through.
"We have put in place some countermeasures but I can't disclose the specifics," said Neil Blair. "We have sent takedown notices against Web sites hosting the illicit copies but we haven't filed any lawsuits."
Even thousands of illicit downloads would be no more than a drop in the ocean for a book that sold 8.9 million copies in 24 hours. But the Potter piracy is likely to add to media companies' fears that online file-trading is a threat to nearly every aspect of their businesses.
In recent months the hottest movie of the summer, "Star Wars: Episode III --Revenge of the Sith," and one of the hottest records, Coldplay's "X&Y," were both leaked online immediately after their release.
Rowling has yet to make a deal to publish her books in a downloadable format, even as Audible and Apple's iTunes Music Store have used the popularity of portable music devices like the iPod to make downloadable audiobooks one of the fastest growing parts of the overall audiobook sector.
Rowling has railed against unauthorised ebooks. "You should NEVER trust any Harry Potter ebooks offered for download from the internet or on P2P/file-trading networks," she wrote in January, warning they may also expose users to computer viruses or fraud.
Hard-copy piracy has also spread to India, where street vendors have been seen hawking illegal copies at steep discounts