Anyone familiar with file-sharing operations and those who seek to disrupt them will be aware that there are many techniques used by both sides to thwart the other. While tracking solutions, fancy technology and sheer numbers perpetuate the fight, there are claims that a more traditional technique is in use against file-sharers - good old-fashioned blackmail. But that weapon can work both ways.

Today’s wars, no matter where they are fought or who is fighting them, are increasingly exposed to public scrutiny. While there are accepted guidelines for engaging in battle to which conventional and accountable forces must adhere, there are plenty of exceptions to these rules and many transgressions go on undiscovered.

In the ongoing Internet conflict between file-sharers and pro-copyright groups, there are many fighting fronts. While much diplomatic pressure is exerted to create new laws and tighten up existing ones, other elements are using those laws to take down file-sharing sites and threaten ISPs. On the Internet itself, anti-piracy groups work largely covertly, spying on users and file-sharing sites and services alike, gathering intelligence on a daily basis.

Since it is largely unseen, this type of anti-piracy activity remains somewhat of a mystery. How do the movie and music industries gain access to the most exclusive private trackers and FTP sites? How do they gather evidence on both site operators and site content for months without being detected? Perhaps of even more interest is how they manage to gather personal information on users of those sites.

Antipiratbyrån (APB) regularly make the pages of TorrentFreak since it is one of the most active online anti-piracy groups. It has been effective in its investigations against individual file-sharers and has managed to infiltrate a number of exclusive piracy hangouts. How it did this has largely remained a mystery but according to a report from Sweden, some of that information is being obtained by old fashioned blackmail.

From a source who has previously worked in law enforcement and also in the private sector, news outlet Nyheter24 has now revealed that APB have been tracking down teenage file-sharers and threatening them with reprisals unless they snitch on their friends and hand over information on the sites they use.

Citing a situation which happened a few years ago, the source explains how APB received a tip that people were sharing files via a research institute FTP server. APB allegedly contacted a known file-sharing employee at the location and threatened the individual with reprisals unless they handed over information and helped with their investigation. APB subsequently used the employee’s login to access the server.

APB later threatened to take the case to court unless material on the FTP server was deleted. Fighting back, the research institute threatened to report APB for hacking. In the end a settlement between the two sides was reached in private and no further action was taken.

On a very similar theme, just recently Swedish prosecutor Björn Ericson announced that there would be no investigation into the activities of APB despite allegations that they had gained unauthorized access to another FTP server, this time in the ongoing ePhone case.

“There was not enough concrete information about a specific crime,” concluded Ericson.

While anti-piracy groups and copyright holders aren’t immune to the law, they do work to less strict guidelines than the police do when they conduct an inquiry into a criminal case. Their quest to manipulate individuals through fear is a common strategy.

Last year, representatives from several indie music labels infiltrated a private BitTorrent tracker with the aim of gathering information on both users and admins and using that data to force it to close down. One member, who had uploaded a lot of music to the site, was befriended by the infiltrators and over a period of several months was persuaded to part with sensitive information on site staff and other users. Armed with that information the label workers later revealed themselves to the site’s admin, along with a threat – close down or else. They quickly learned that two can play that game.

With assistance from moderators at other sites, the tracker’s staff used the huge amounts of data they held on the infiltrators, from email addresses through to several pages of IP addresses, to hunt down their adversaries on other sites. There they found the same users happily downloading movies, software and TV shows, along with plenty of incriminating forum posts and in one case, a home address. That address led to a phone number, which led to an unexpected late-night phone call.

Blackmail, it seems, can cut both ways.