Sony has lost a legal battle in Australia over the modifying of its PlayStation games console.
PlayStation consoles have controls to counter game piracy
The High Court has ruled that chipping the console so that it can play imported games does not breach copyright law.
The ruling ends a four-year legal battle between Sony and a supplier of so-called mod chips, which bypass regional controls on the machine.
In the UK, the selling of mod chips was ruled illegal in 2004.
Consoles such as the Xbox and PlayStation 2 can be modified by chips that are soldered to a console's main circuit board to bypass copyright and regional controls.
The chips allow people to play games purchased legitimately in other countries, as well as running backup copies or bootleg discs.
The case in Australia revolved around retailer Eddy Stevens who supplied and installed modification chips in PlayStation consoles.
A modded console lets gamers play imported games which are cheaper than those sold in the country.
It also means fans can play the latest games from the US and Japan way before a title is officially released in Australia.
Sony argued that the mod chips were a breach of copyright under Australian law.
After a series of conflicting judgements from different courts, the High Court has come down on the side of Mr Stevens.
It ruled that mod chips do not breach copyright. It decided that while the chips let gamers play copied or imported games, they do not enable the copying of games.
"There is no copyright reason why the purchaser should not be entitled to copy the CD-Rom and modify the console in such a way as to enjoy his or her lawfully acquired property without inhibition," said the court ruling.
"Sony sought to impose restrictions on the ordinary rights of owners, respectively of the CD-Roms and consoles, beyond those relevant to any copyright infringements."
"In effect, and apparently intentionally, those restrictions reduce global market competition," said the judgement
A lawyer for Mr Stevens said the judgement would allow Australian consumers to buy lower price versions of games overseas and play them on their modded consoles.
"This is a hell of a victory for the consumer. That's why we did it," Mr Stevens told Australian television.
Sony Australia said it did not have any comment to make at this stage.
In other countries, the selling of mod chips is banned. In the UK, both Microsoft and Sony have used the EU Copyright Directive to clamp down on mod chips.
Under that directive, it is illegal to circumvent copy protection systems.