Games developer Valve has reportedly been cracking down on those who have downloaded illegal copies of its latest release, Half-Life 2, or those who've tried to bypass its Steam security system with a CD key.

The company has allegedly banned up to 20,000 users from playing the critically acclaimed PC first-person shooter game.

"The number of people who actually had bought Half-Life 2 and used the CD key cheat was very small. Very small. Most people just tried to rip off the game and not bother buying it," said a Valve spokesperson.

The company's heavy-handed approach has been understandable – piracy has plagued the PC industry for years, with games being available within days before or after release. Valve suffered a blow with the source code leak last year, forcing the company to delay the game by a year.

Online authentication has received mixed feedback from consumers, namely due to longer load times and the complications that arise when facing busy servers. However, if Valve's approach proves to be successful in warding off piraters, more game companies will likely follow suit.