A controversial law firm that sent letters to alleged illegal file sharers has been told it cannot drop its cases to "avoid public scrutiny".
ACS:Law contacted thousands of people accusing them of illegally downloading movies and songs and demanding payments of £500 to avoid court action.
Cases against 26 of them proceeded, before the company attempted to pull out of prosecution at the last minute.
Now a judge had criticised the firm for its methods.
"I cannot imagine a system better designed to create disincentives to test the issues in court," said Judge Colin Birss at the Patents County Court in London.
The case stems from a letter-writing campaign by ACS:Law and its partner company MediaCAT, which sent an undisclosed number of notices to alleged file sharers demanding they pay a fine or face the prospect of costly legal action.
Some of those contacted paid up, but it later emerged that the two companies had been taking 65% of the fines collected, with the minority of the money being passed back to the copyright holders in question, most of whom remain anonymous.
Those tactics - known as "speculative invoicing" - had come in for heavy criticism from those who claimed that the action was unfair.
Consumer group Which? said it had found several instances where plainly innocent people had received the demands.
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