Producers of the Oscar-nominated movie are using a controversial legal maneuver to hunt down pirates.

Dallas Buyers Club is suing the Dallas Non-Buyers Club.

The rights-owner of the Oscar-nominated film has filed a lawsuit against 31 anonymous torrent users for sharing the Matthew McConaughey film.

The copyright lawsuit was filed this week in the Southern District of Texas. The plaintiff says it has used "geolocation technology" to trace the IP addresses of the defendants there. According to the complaint, the John Doe defendants are participating in a torrent "swarm" that is reproducing and redistributing the movie.

"Each time a Defendant unlawfully distributes a free copy of Plaintiff's copyrighted movie to others over the Internet, each person who copies the movie then distributes the unlawful copy to others without any significant degradation in sound and picture quality," says the lawsuit. "Thus, a Defendant's distribution of even one unlawful copy of a motion picture can result in the nearly instantaneous worldwide distribution of that single copy to a limitless number of people."

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Dallas Buyers Club was co-produced by Voltage Pictures, which in 2010 was one of the pioneers of a breed of copyright litigation called "mass joinder" that soon become trendy among some independent and adult production companies. Four years ago, Voltage sued thousands of alleged pirates for seeding Oscar-winning The Hurt Locker onto torrent sites. Since then, copyright lawsuits against "John Does" have flourished.

Typically, after such a mass joinder lawsuit is filed, a subpoena is delivered to an ISP for the purposes of identifying a flagged customer by name and address. Then comes settle-or-else demands.

In response to subpoena requests from copyright owners, a few public advocates have filed motions to quash. This has divided the nation's judiciary.

Some judges have been less than tolerant of the mass joinder approach. One judge a few weeks ago noted that it was possible that an anonymous defendant was the victim of an open WiFi connection. Another judge expressed concern about the "unseemly practice" of joining defendants together.

Still, there are other more permissive judges out there. For example, on Wednesday, one Ohio magistrate judge declined a motion to quash a subpoena in such a mass joinder case.

The latest lawsuit over alleged Dallas Buyers Club piracy marks the most high-profile film attempting to employ this controversial anti-piracy technique since The Expendables in 2011. Here's the complaint.

Dallas Buyers Club was released on Nov. 1. According to data compiled by Portland, Ore.-based computer programmer Andy Baio, the film's screener leaked on Jan. 3. By the end of the month, after Oscar nominations were announced, the film was one of the 10 most pirated films on torrent networks.

Email: Eriq.Gardner@THR.com

Twitter: @eriqgardner