Over 7,000 books are available free on-line in breach of copyright, according to a new report from UK-based internet monitoring company Envisional. According to the company, popular titles such as the Harry Potter series are being swapped on Napster-type services.

The piracy gives the publishing industry similar problems to those experienced by the recording industry through the rise of on-line file-swapping services.

Two main methods were used in copying the books onto the web. The most common method is to have traditional print books scanned and converted into an electronic format. The other option is to offer “cracked” copies, where the copyright protection mechanism in e-books is disabled.

Envisional recently developed search technology which tracks down illegally copied material such as this on the internet. Its Automated Anti-Piracy System (AAPS) claims to find infringing material on the web and alerts the owners