Firms that let staff watch the World Cup on broadband have been warned they could be fined £1,000 if they do not have a TV licence.
Are you watching the World Cup on your PC?
With the BBC streaming more than 50 hours of World Cup football to UK internet users, the TV Licensing Authority says it is poised to target businesses that break the rules.
Do I need a licence?
The law says that anyone who uses a TV, or any other device, to receive TV signals, must buy a licence.
This includes video recorders, set-top boxes and DVD recorders.
You will also need a licence if you use your computer to watch live broadcasts.
Why do I need a licence for my PC?
You only need a licence if you use your computer to watch programmes at the same time as they are being shown on TV.
Before now, this has not been a major problem as very few programmes are available simultaneously on air and online.
Computer users only needed a TV licence if they had a special video card that could receive TV signals.
But the TV Licensing Authority now says watching the BBC's World Cup coverage over broadband will require a licence.
This is to stop people receiving TV programmes for free on their computer when they would have to pay to see them on a regular television.
Is this just about the World Cup?
No. The TV Licensing Authority says you need a licence to watch any TV station broadcasting within the UK on your computer.
However, you are free to watch archived programmes or downloadable clips without a licence.
Why are businesses being targeted?
According to the Broadcasters' Audience Research Board (BARB), 98% of households currently own TVs and therefore already require valid TV licences to watch TV programmes.
So the vast majority of people do not need for separate TV licences for PCs, as they would already be covered by any valid TV licence they may have.
Businesses are less likely to have TVs, and are therefore less likely to possess a licence - so the Licensing Authority wants to clamp down on employers who let their staff watch the World Cup online.
How do they know who needs a licence?
Under the Wireless Telegraphy Act 1967 (as amended), anyone who sells or hires television receiving equipment must notify the TV Licensing Authority of their customers' names and the address where the equipment is to be installed.
These details are cross-referenced against a database of over 28 million addresses to find out whether people have applied for a valid licence.
The Authority then targets properties without licenses to find out if anyone is breaking the law.
However, the law does not yet require retailers to notify the Authority when people buy PCs, unless they are pre-configured to receive TV signals - so there may be some gaps in their records.
Where can I get a licence?
TV Licences are available online from the Licensing Authority's website.
You can also purchase one from the Post Office, or at one of the 14,000 PayPoint outlets across the UK.
How much does it cost?
A colour TV Licence costs £131.50 and a black and white licence costs £44.
There are some concessions for the blind, and there is no charge for people over the age of 75.
The cost to businesses varies, but they will generally only require one licence to cover an entire building.