A UK Sunday newspaper this weekend alerted its readers to a potential payment from Microsoft Corp if the Redmond, Washington company is ruled a monopoly in the US Federal court. Under US law, a company found guilty of overcharging is liable to reimburse customers up to three times any amount ruled to be an excess payment. In an interview with London’s The Observer newspaper, lead prosecutor for the US Department of Justice, David Boies, said overseas customers are entitled to receive the same compensation as any offered to US citizens.

Microsoft is said to keep 65% of operating system payments as profit, and if the Federal Court rules against it in its ongoing antitrust case, a portion of this may be ruled an excess payment. Although the compensation available to individual purchasers in the US and elsewhere may be small, the claims of millions of customers could be aggregated under class-action suits which would seek to demand millions of dollars from Microsoft. The Observer speculated that the compensation bill to UK customers alone might run as high as $500m.