As part of their ongoing legal case the MPAA has requested that isoHunt hands over the IP-addresses of users who downloaded torrent files via the popular BitTorrent search engine. The Hollywood group says it requires unredacted IP-addresses to show that infringements took place in the United States. IsoHunt, however, is refusing to hand over any data that can be used to identify individual users.

For more than seven years isoHunt and the MPAA have been battling it out in court, and in recent weeks the case has heated up once more.

After the 2010 District Court ruling against the torrent site was affirmed in March, the case is now moving towards a trial later this year from which the movie industry hopes to win up to $750 million in statutory damages.

To secure this amount the MPAA has to prove direct infringement and show that United States users either uploaded or downloaded copyrighted works. In addition, they will have to show that they are the rightful owners of the files in question.

Previously, the court had already ordered isoHunt to hand over download information to the MPAA, including IP-addresses of users. At the time the location of the downloaders wasn’t an issue so the IP-addresses were redacted. Earlier this month, however, the MPAA requested the same data without redactions.

After a week isoHunt’s legal team replied to this request via email, explaining that the original 2007 data was lost in a server crash. However, the server logs of the past five years are still there, and isoHunt is prepared to hand these over as long as the last digits of the IP-addresses are redacted, along with several other privacy guarantees.

“To address privacy concerns, Defendants will agree to produce the data with the last octet blocked out, designated as highly confidential pursuant to the protective order, and subject to a stipulation that plaintiffs will never use it for anything other than to identify country of origin of the users and will promptly destroy the data once the litigation concludes,” isoHunt lawyer Jennifer Golinveaux wrote.

The MPAA wrote back with assurances that without a court order it would not attempt to identify any individual website user from the IP addresses. This response suggested that the movie studios do not agree to the redaction that was discussed in a previous conversation, and a follow-up email confirmed this stance.

The MPAA is worried that isoHunt’s legal team will challenge the accuracy of the location data obtained from partial IP-addresses, and without assurances that this issue will not be brought up in court the movie group needs unredacted addresses.

“At this point, we need the full IP addresses. Defendants have made it clear that they intend to challenge the geographic location of downloading users. I have two or three times now said we would consider accepting the IP addresses with the last octet redacted provided that defendants will stipulate not to challenge the results of geolocation analysis of IP addresses with the last octet redacted,” MPAA’s Steve Fabrizio wrote.

Dissatisfied with isoHunt’s offer in response to the lost data, the MPAA said it was running out of time and filed a motion for evidentiary sanctions last week. Among other things, the movie studios asks the court to rule that all of its movies and TV-shows have been downloaded at least 2,000 times by U.S. users through the isoHunt website.

“The missing website data, which Defendants have not produced (and, in material respects, have irreversibly despoiled), would have conclusively proven direct infringement by Defendants’ users and would have been important evidence on the issue of damages,” the MPAA tells the court.

In response, IsoHunt told the court yesterday that there is no basis for these sanctions as they were willing to solve the issue by producing new server logs. In addition, isoHunt criticized the MPAA’s entire motion.

“Copyright infringement carries statutory damages of up to $150,000 per work infringed. Plaintiffs should not be allowed to short cut proving the most basic elements of their damages case based upon nothing more than bald distortions of the record,” isoHunt’s legal team writes.

It is now up to the court to rule on the request, which will also decide on the fate of the server logs.

A ruling in the MPAA’s favor means that no IP-addresses will be handed over, but it will put isoHunt at a severe disadvantage. Should the court deny the MPAA’s request for sanctions then the MPAA and isoHunt will have to reach an agreement on how the addresses will be redacted.

Update September 12: isoHunt informed us that they have an agreement with the MPAA not to hand over underacted IPs. The last octet will be redacted as “1” and MPAA will use it only to identify the location of downloaders. isoHunt agreed not to raise the location issue (with regard to the redacted addresses) in court.