In the ongoing court battle between the MPAA and the cyberlocker Hotfile, Duke University Law Professor James Boyle has filed an important expert report. Countering claims from the movie industry that Hotfile has few non-infringing uses, the Professor shows that the most downloaded files on the cyberlocker are Open Source software. In addition, he argues that affiliate programs are useful for compensating content creators for their efforts.

Last year the MPAA started a lawsuit against Hotfile, one of the Internet’s most popular cyberlocker services.

The movie studios claim the file-hoster is promoting “massive digital theft” and want it to be shut down, an accusation Hotfile fiercely rejects. In recent months both parties have filed dozens of papers at court supporting their respective arguments.

The MPAA describes Hotfile as a piracy haven akin to the likes of Megaupload. To substantiate this accusation the studios hired an expert who claimed that more than 90% of all downloads on the site are copyright infringing.

In response Hotfile hired an expert who discredited the report, describing it as both “unreliable” and “unscientific.” And the defendant didn’t stop there.

TorrentFreak has obtained a confidential report where Duke University Law Professor James Boyle presents some revealing facts about the non-infringing use of Hotfile. The document was filed under seal last month and reveals that sharing of non-infringing content is widespread on the cyberlocker.

While the Professor does not assess what percentage of content on Hotfile is infringing, he does note that the two most downloaded files on the site are Open Source software. With 885,583 and 629,783 downloads respectively, the Open Source applications iREB and Sn0wbreeze were most shared, something Boyle believes the court should take into consideration.

“The fact that it is highly likely that the two most commonly downloaded files on Hotfile are open source programs that seem to be licitly shared appears relevant to any assessment the court might make about the current usage of the system,” the Professor writes in his report.

Linked to the popularity of the above applications, Boyle brings up another important argument. While the MPAA and others claim that affiliate programs which compensate users for generating downloads are solely setup to promote infringements, several software developers actually use them to generate revenue from their free programs.

“At least two of the open source developers featured in this study were active participants in Hotfile’s ‘Affiliate’ program, thus being indirectly compensated for the programs they were freely providing to the public. This suggests that the Hotfile Affiliate program is capable of fulfilling the valuable function of compensating authors and distributors,” Boyle adds.

The legitimate use of Hotfile doesn’t stop with Open Source software either. The Professor cites several other examples, from distributing a public domain version of Huckleberry Finn to sharing Creative Commons licensed movies.

Finally, the report argues that cyberlockers such as Hotfile provide a very important function to both average users and professional content creators. They are one of the few options people have to conveniently distribute large files.

“Hotfile provides a type of service that is very important in the architecture of the Internet. Transferring large files over the Internet is difficult. Gmail’s maximum file attachment size is 25MB, for example, and most email systems set lower limits.”

“Independent open source developers or filmmakers collaborating on an open source film do not necessarily have their own servers from which material can be shared. The growth of distributed creative activity on the Internet suggests that the already important role for services such as Hotfile is likely to grow in the future,” Boyle concludes.

While we can be certain the MPAA will try to downplay the non-infringing use of Hotfile, it is now up to the court to judge how the points raised by Professor Boyle are weighed.