Thousands of pub landlords face heavy fines or jail as the Premier League and BSkyB begin a campaign of prosecutions against pubs that illegally broadcast English football matches.
The hardline approach follows a court judgment earlier this month in which the Premier League won a copyright ruling against British pubs that use non-UK decoder cards to show games.
The Premier League and BSkyB will signal their intent in warnings placed in adverts running in the drinks trade press today.
It follows a case brought by the League against satellite TV company QC Leisure. In a High Court ruling this month, Judge David Kitchin found that pubs violate League copyright when customers can view footage of previous games, logos, pre-recorded video sequences and anthems that are not authorised for use across borders.
As a warning of what is to come, an Essex landlord was this month ordered to pay more than £19,000 in fines and costs after being convicted of showing Premier League and international matches via Sky Sports without a commercial viewing agreement.
Frederick Young, licensee of the Rose Inn in Shenfield, was convicted on 6 February at Basildon Magistrates' Court and fined £2,500 for each of six offences of dishonest reception of a television transmission.
Young, prosecuted under the Copyright, Designs and Patents Act of 1988, was also told to pay £4,522 in costs.
In a further development, one of Britain's main distributors of foreign boxes and cards, Euroview, has ceased trading.
In a notice posted on its website this month, it said the latest High Court judgment found the Premier League was "entitled to copyright protection of certain artistic works and graphics that formed part of the relevant broadcasts of football matches in these proceedings".
It warned: "There is now the prospect that companies providing a service that allows the 'communication to the public' of any such artistic works could cause their customers to be liable for copyright infringement." The company told customers that their accounts with it would cease on 10 February.
Next week in the High Court, a Portsmouth landlady, Karen Murphy, who was convicted after using a Greek decoder to show matches, will seek to have the case against her overturned.
Ms Murphy was paying £118 a month to show games in her pub, The Red, White & Blue, as opposed to the Sky subscription of £480.
She has taken the case to the European Court of Justice, which delivered a complicated ruling that should see her prosecution and £8,000 fine overturned in the High Court but still upheld the League's right to copyright.
Since that ruling, Premier League content has been developed to include more logos and symbols that uphold its ownership of the material, meaning landlords cannot flout the rules by turning the television on and off at key times.
Despite next week's hearing, the League and BSkyB believe the QC Leisure ruling is the more significant.
The thousands of landlords potentially under investigation would include those suspected of breaching League copyright by using illicit foreign feeds to show games as well as pubs that screened Sky's matches bought with a domestic subscription and not featuring the "pint glass" on-screen symbol showing the subscription had been purchased for commercial use.
Today's campaign of warning adverts is likely to trigger fresh activity in the courts as officials from the Federation Against Copyright Theft and other investigators step up visits to pubs suspected of showing matches unlawfully.