The poor opening weekend performance of “Expendables 3” last month was in part blamed on piracy, and now producer Millennium Films is going after those who downloaded the film via torrent sites.

CEG TEK International, representing Millennium, has been sending out notices of unauthorized use of copyrights to the IP addresses associated with the downloading, directing recipients to a settlement website or risk legal action.

Copies of notices posted online include a warning that the recipient could face monetary damages if a lawsuit is commenced for the “unauthorized copying and/or distribution” of the movie.

Major studios have been pursuing sites that engage in large-scale piracy, not individual torrent users. The latter is a legally cumbersome process that typically brings negative P.R. Lionsgate pursued sites that posted pirated copies of “Expendables 3,” winning a restraining order against six sites. Estimates were that it was downloaded by 2.2 million people before it even premiered.

But individual producers have sought legal action on their own, including producer Nicolas Cartier, who sought individual file sharers of “Hurt Locker,” offering reported settlements of between $1,500 and $2,500.

His Voltage Pictures was co-producer of “Dallas Buyers Club.” Producers of that movie have also been pursuing torrent users who downloaded and shared that movie, with more than 100 lawsuits filed in federal courts across the country, seeking to track down the identities of individual John Doe defendants via IP addresses. The suits typically seek to subpoena Internet providers to disclose the holders of the accounts. Some of the lawsuits threaten damages of up to $150,000 for each case of infringement.

Ira Siegel, the attorney representing CEG TEK, confirmed the action but referred further questions to his client.