By Jim Reed
'Helen' from Hull was sent a letter in the post demanding £500
Thousands of internet users have been told they'll be taken to court unless they pay hundreds of pounds for illegally downloading and sharing hardcore porn movies.
Newsbeat's found out that people across the UK have been accused of using file-sharing networks to get hold of dozens of adult titles without paying for them.
A German company called DigiProtect claims the users are breaking copyright law and is demanding £500 to settle out of court.
A 20-page legal letter lists the name of the film involved along with the time and date of the alleged download.
Lawyers say they have been contacted by hundreds of worried individuals over the past few weeks.
Many deny copying the movies and say they have no idea why they were identified in the first place.
Michael Coyle from Southampton-based solicitors Lawdit is acting on behalf of hundreds of people who have already received legal papers in the post.
"It's the embarrassment factor," he said. "One lady told us she fainted when she opened her letter. Teenagers right up to old-age pensioners have been accused of downloading hardcore porn. The overriding feeling is one of outrage."
'Upset and angry'
Twenty-seven-year-old 'Helen', not her real name, from Hull, told Newsbeat she was "upset, scared and angry" after a letter landed on her doormat last month demanding £525 for sharing a single adult movie over the net.
"It's a big letter accusing me of downloading a porn film called Young Harlots In London. "I've never heard of it before, certainly never seen it and never downloaded it."
"I got a letter from my ISP a few months back saying that they had received a court order which meant they had to release my details to a law firm."
"I waited for the letter to turn up. It gives me three weeks to pay up, or they'll take me to court."
"I think their methods of going about this have been completely wrong. They are terrifying quite a number of people."
Sixty-year-old 'Mary' from Bedfordshire received a similar letter.
"I'm a pensioner, so it was such a shock. I didn't even know what a P2P network was before this," she said. "I didn't sleep for a week."
The illegal sharing of copyright material over the web is a major headache for music, movie and game companies.
Six million people in the UK alone are thought to download music and movie files for free each year with more than half under-25s said to use file-sharing networks like Gnutella, BitTorrent and eDonkey.
When an individual user downloads sections of a film or song over the network, they are simultaneously uploading different parts of the film to other users.
The government recently brokered a deal between record labels and internet companies that was meant to discourage this kind of illegal copying.
Michael Coyle is acting for people who've received the letters
Broadband providers like BT, Tiscali and Virgin agreed to send warning letters to customers identified by the music industry body, the BPI, as illegal file-sharers.
A handful of independent music and gaming companies have gone further and started taking direct legal action.
But this is thought to be the first time pornographic material has been targeted.
Michael Coyle said: "The cynical lawyer in me would say this is a money-making exercise.
"If you send out 10,000 letters and ask for £500 each time, you only have to get half to pay up and you've made a significant amount of money.
"Because it is porn, the person who's being accused won't want to go to court and is more likely to pay up to make the matter go away even if they are completely innocent."
Lawyers representing DigiProtect say the £500 demand is calculated as a token sum in damages for lost sales plus the "considerable" costs involved in obtaining evidence and legal fees.
Little is known about DigiProtect, the German firm behind the latest wave of copyright litigation.
The company is based in Frankfurt and brands its business with the motto "turn piracy into profit".
It has represented a range of rights holders in the past including the German techno band Scooter.
It tracks down alleged pirates by logging the individual Internet Protocol, or IP, address of internet users logged on to file-sharing networks.
It then applies to the High Court to force broadband companies to release the physical contact details of customers matched to those addresses.
In legal letters to internet users seen by Newsbeat, the company claims: "Each copy… represents a potential lost sale and is tantamount to someone walking into a shop and taking a physical copy without paying for it and then giving a copy to anyone who asks for it."
But critics claim the technology DigiProtect uses to track internet use is unreliable.
The websites that allow users to access the file-sharing network have told Newsbeat that fake IP addresses are routinely entered into the system to throw companies like DigiProtect off the scent.
The growing popularity of wireless, or WiFi, networks in the home means it is easy to share an internet connection with a neighbour, especially in a block of flats.
"It's positively encouraged to have an open wireless network these days," said Michael Coyle at Lawdit. "Most people use very standard default passwords so it's very easy to use someone else's WiFi."
Lawyers representing DigiProtect claim the technology behind the company's tracking process is "highly sophisticated" and has been backed by courts in Europe.
They say it is the responsibility of broadband users to ensure they will not allow others to use their internet connections for unlawful purposes like illegal file-sharing.
Many of the letters seen by Newsbeat indicate that DigiProtect is acting on behalf of one of the biggest adult studios in the United States, Evil Angel, run by American porn mogul John Stagliano.
When contacted, Mister Stagliano appeared to be unaware of the £500 DigiProtect is demanding from alleged file-sharers to settle out of court.
"It's not my understanding that they ask for anything near that. I think the amount was $50 (£34) or €50 (£43)," he said.
"I would be very surprised and I wouldn't be happy because it would mean it was completely misrepresented to me."
DigiProtect refused to comment directly for this article.
But in a statement, its legal representatives Davenport Lyons said: "[The £500 settlement fee] consists mainly of the cost of the considerable work required to identify the owner of the IP address.
"The sum in the settlement is a fraction of what would be ordered by a court if an individual were found liable after a trial.
"There is no compulsion on the individual to accept this settlement if he is innocent."
"Where submissions are made (such as someone claiming that they have not uploaded the copyright material or that the ISP has wrongly identified them as the owner of the IP address) we look into these carefully before deciding whether to proceed."
"The lawyer representing people accused who says this is a money making scheme is simply wrong.
"This action is designed to prevent further illegal exploitation of our client's copyrighted material and the settlement sum in no way compensates for the loss suffered or the cost of getting the settlement."