The Business Software Alliance (BSA) has taken steps to more assertively combat online fraud as part of its continuing fight against software piracy.

Simultaneous international legal action has been taken against five alleged software pirates, one in the US, one in the UK, one in Austria and two in Germany, marking the beginning of BSA's international enforcement efforts against people selling illegitimate software online.

'To all offenders out there, large or small, our message remains the same: software piracy is illegal and we will be bringing legal actions against internet pirates to tackle this serious problem' said John Wolfe, BSA director of internet enforcement. 'The international litigation announced yesterday is just the beginning of our expanded efforts to fight global software piracy.'

In all these cases, the BSA was alerted to the illegal activity being conducted by reports and complaints from many disappointed consumers who had been duped when they were attracted by low price deals, but received counterfeit or poor-quality products for their money.

A recent report from analyst IDC suggested that 25 per cent of products purchased and downloaded directly from online sources, other than the vendor, contains malicious code or additional software code, which could impact on IT security and performance. In test purchases from auction sites IDC also reported that there is a less than 50 per cent chance of buying genuine, licensed software that had not been tampered with.

'Unfortunately, along with the explosive growth of internet use and online shopping, there is an increase in consumers' exposure to illegal software,' said Peter Beruk, BSA's internet committee chairman. 'At BSA, our goal is to educate the public about how they can protect itself from fraud and to enforce compliance with copyright laws.'

During 2006, BSA shut down online auctions offering more than 20,000 softw are products with a total value of more than $17m (£8.8m). BSA also sent notices regarding over two million non-auction infringing copies of software with a total value of more than $12m (£6.2m).

In the US, BSA shut down 8,025 auction sites and 5,961 sites internationally - giving an indication of the scale of the problem.

The defendant in the US case is an online seller in Pennsylvania who was operating 20 web sites offering copies of Adobe, McAfee, Microsoft and Symantec software.

In the UK case, the defendant is a web site operator offering copies of Autodesk software.

In Germany, the three identified web sites were offering Adobe products.

In two cases, preliminary injunctions have been issued and the site-owners' property searched for evidence of illegal sales. In the third case, an injunction was issued in Germany, but the operator's headquarters was found to be located in Austria, where a complaint has since been filed.