When a couple (we'll call them the Smiths) received a letter from their ISP—one saying they were being threatened with a copyright lawsuit—they were scared. The middle-aged immigrant couple moved to the United States from Eastern Europe more than a decade ago. Both have advanced degrees, but they knew very little about the US legal system. They denied (and still do deny) the plaintiff's accusation that they downloaded a pornographic film on BitTorrent, but the Smiths were still worried about the consequences of being sued.

"We never were involved in the legal process," Mr. Smith told us in a phone interview. "I didn't know the difference between criminal cases and civil cases. I was totally ignorant."

The Smiths' predicament has become increasingly common. So-called "copyright trolls"—often law firms representing third-tier pornography producers—have threatened tens of thousands of users with lawsuits for allegedly sharing copyrighted pornography on peer-to-peer networks. A key part of the troll business model is that the cost and embarrassment of a public lawsuit involving pornography can be enough to intimidate even some innocent users into paying the trolls' ransom.

The Smiths decided that hiring a lawyer would be too expensive. So, after some online research, they drafted a motion to dismiss the lawsuit themselves. The judge didn't grant the Smiths' motion, but the plaintiff only pursued a handful of the "John Doe" defendants in the Smiths' case. After a few months of anxious waiting, the Smiths concluded that their adversary had moved on to other targets.

Now out of danger, the Smiths wanted to share what they learned with others facing the same threat, so they established a blog called Fight Copyright Trolls in May 2011. Nearly two years later, the blog has emerged as the nerve center of a growing community of anti-troll activists. And SophisticatedJaneDoe, the couple's shared online persona, has become a de facto leader of the Internet's grassroots anti-troll movement.

The emergence of sites with names like Fight Copyright Trolls and DieTrollDie is creating headaches for the porn trolls. The trolls' threats often rest on shaky legal foundations, but they've been able to intimidate many victims into paying up anyway. Anti-troll sites closely monitor ongoing troll lawsuits, publicize troll misconduct, and offer their fellow John Does advice on fighting back. By providing victims with accurate information and moral support, anti-troll sites make it much harder for trolls to intimidate them. And by documenting trolls' misconduct, they provide defense attorneys with ammunition to discredit the trolls in the eyes of judges.

“It’ll freak her out so badly that it might put her off eating.”

In recent weeks, Ars has talked to several important figures in the anti-troll community. For many of them, like the Smiths, the issue is personal. Copyright law wasn't even on their radar until they got a letter from their ISP about a copyright lawsuit. Some victims found the experience so infuriating that they emerged determined to help others facing the same threat.

Does helping Does

"My elder mother (68-years-old) just received the letter from her ISP. She asked me to look it over and tell her what it was all about," reads one comment posted to Fight Copyright Trolls in September. "Can’t really afford a lawyer but I don’t want my mother being harassed and I’m afraid if they get her info she’ll fold and pay the ransom, I mean settlement, which she can hardly afford."

Within half an hour, another reader named Raul weighed in with helpful information. He provided a link to a free copy of the docket for the case, allowing the original commenter to read past filings. And he suggested a lawyer who may be able to represent the commenter's mother pro bono.

"I still haven’t told her the real situation, it’ll freak her out so badly that it might put her off eating," the reader wrote. "I’m hoping to get a plan together this/next week after some more reading."

Raul pointed out that under the discovery rules established by the judge, the troll would only be allowed to get the woman's mailing address, not her phone number.

"W/no phone #s released I may just try to have my mother ride this out," the commenter responded. "Thanks again!"

This kind of interaction is a regular occurrence at Fight Copyright Trolls. Every day, new users get threatening letters and show up on the site looking for help. Others with more knowledge and experience fighting trolls offer information, advice, and encouragement. Some of the people who get help on the site become site regulars and help other users in turn.

"I was glad that the community formed," Mr. Smith said. "I'm glad they started helping because I definitely have no time. I have a full-time job. It would be a nightmare if I had to answer every question of the thousands and thousands of newcomers. I was happy that people started doing what I hoped they would do: answer questions to help each other."

Still, Mr. Smith (who recently has been more active on the site than his wife) spends a couple hours a day working on helping troll victims and exposing troll misconduct. He writes posts, responds to comments and e-mails, and keeps up with the latest news on Twitter.