They have called in a former Scotland Yard fraud expert to track down the dodgy landlords.
The guilty face jail for six months or unlimited fines if the courts apply the maximum penalty for infringing copyright acts.
Each Saturday afternoon, thousands of football fans pack drinking dens around the country to watch top games — even though UEFA rules strictly forbid live coverage of any Premiership matches here between 2.45pm and 5.15pm.
Equipment suppliers advertise themselves on the internet.
Malcolm Chamberlain, a director of AV Station plc in Chichester, admitted he plugs his customers into the Nova system from Greece. He said: "We've sold tons of systems. I can't even tell you how many. It's manic. The phone goes non-stop.
"I ask people to sign our closed period disclaimer and what they do after that is entirely up to them. But every pub I've been in on a Saturday which has our system is, by and large, showing the live football.
"Some just shut the doors and put a sign up ‘Closed'.
"There haven't been many prosecutions and if Sky or the Premiership want to do anything about it then either the publican or ourselves will put it into the European Court."
United v Blackburn yesterday could be picked up by tuning in to the signal used by EIGHT different TV companies, including Art In Africa, Sports TV in Portugal, Sky, Calcio 3 in Italy and TTS Foot in France.