SANTA MONICA, CA — The file-sharing blog TorrentFreak has caused a minor online kerfuffle by outing anti-piracy operation MediaDefender as a friend to porn. On September 20th, TorrentFreak accused MediaDefender of padding its profits with revenue earned by redirecting users of file-sharing networks to adult websites.MediaDefender works by seeding the peer-to-peer file networks with thousands of decoy and spoof files that frustrate users attempting to find pirated movies and music. According to published reports, the company earned $4,000 to protect just one album and $2,000 for a single track; one large movie studio paid MediaDefender $3.6 million to protect four movies.

According to TorrentFreak, however, MediaDefender may have earned — or be earning — even more from the adult entertainment industry.

“From leaked [internal MediaDefender] emails, we’ve now learned … MediaDefender was spamming Limewire and other file-sharing networks with thousands of porn-related files, trying to convert P2P users into paying porn subscribers,” TorrentFreak founder Ernesto wrote.

The leaked emails sent by MediaDefender’s Ben Grodsky mentioned AdultFriendFinder as one of the affiliate programs from which MediaDefender earns revenue. In one email, Grodsky noted, “Adult Friend Finder converts 1 in 2000 on LimeWire. If we want more users, Dylan’s eDonkey messages would get us a lot of Europeans that are a little bit older crowd….”

In another email, Grodsky indicates MediaDefender also owns its own adult websites.

“Paris Hilton and Pamela Anderson ARE in the system,” the email noted. “Some of these are on the PM2 Data Collection owner sending traffic to our porn site. Any ones sending traffic to our porn site (www.enterallsites.com), you can switch over to the MiiVi links that Colin indicated below.”

MiiVi was a video-sharing website launched by MediaDefender in February 2007 to “trap” file-sharers. The site was deactivated on July 4, 2007, after it was unmasked by bloggers.

“It looks like porn was big business for MediaDefender, and we’re curious whether their stockholders are aware of this, since it is never mentioned in any of their financial reports,” Ernesto wrote at TorrentFreak. “Thus far, the adult revenue stream has never been mentioned.

“Today, more than a year after the MediaDefender email leak, EnterAllSites.com is still up and running,” Ernesto continued. “Several other adult domains also owned by the company are still redirected to the site as well.”

Among the adult domains MediaDefender owns, according to an online reposting of an email from Grodsky to one of MediaDefender’s clients, are GirlsGoneWildly.com, ThatsAHotMom.com, WhatAHotMom.com, 8thStreetBitches.com, BitchesILikeToFuck.com, LatinaBrotel.com, BootyBrothel.com, Fuck-A-Flip.com, Puseteria.com, InternationalHouseOfPoon.com, LatinaHaven.com, Lesbowl.com, TitRaider.com and MILFyMan.com. The oldest was registered in January 2005; the most recent registration date was January 2008.