Lawyers can simultaneously sue thousands of anonymous people who share files online, based on a recent court ruling.

Any ruling that makes it easier to sue file sharers could hearten traditional content producers like Hollywood studios and record labels, while inconveniencing broadband-Internet providers, who bear a substantial burden in providing information about their users’ activities in connection with such lawsuits.

A federal judge in Washington, D.C., announced that a mass lawsuit against users of BitTorrent, a popular protocol used by many file-sharing services, can proceed and that Internet service providers now have to give the names of those anonymous users to lawyers. Such mass legal actions like this are typically reserved for court cases that are “logically joined.” Filing each case individually can cost around $350, so this can save lawyers a lot of money.

Judge Beryl Howell said the claims against the anonymous BitTorrent users were “logically related” and allowed the subpoenas to continue — despite some concerns that a number of the users might be outside the operating area of that federal court. Geolocation tools that can identify a geographic area with only an Internet protocol address will let users outside of the federal court’s operating area identify themselves and file motions to be removed from the mass lawsuit.

Copyright owners like the members of the Record Industry Association of America and the Motion Picture Association of America target file-sharing program users because they trade music and movies across the Internet without paying for them. The penalties for being caught illegally sharing music and movies can be very stiff — ranging from enormous fines to jail time.

Howell’s ruling is a bit on the fringe, as many judges have severed mass-lawsuit cases dealing with anonymous file-sharing program users instead of allowing them to be joined together. But the new ruling does set some additional precedent that might open the door to additional mass-subpoena filings. It’s a way to efficiently sue the tremendous number of file-sharing program users on the Internet that are never caught because the process can be tedious and expensive.