European regulators have gone dramatically further than their US counterparts by imposing a record fine of €497 million ($A817 million) and product changes on US software giant Microsoft for stifling competitors

The European Union's competition commissioner, Mario Monti, yesterday announced at the end of a five-year investigation that he was fining the world's biggest software company for abusing its dominant market position. The Italian commissioner also ordered Bill Gates's titan to offer a European version of its all-conquering Windows operating system without Windows Media Player within 90 days. And Microsoft was ordered to disclose "complete and accurate" data to enable rival companies to offer low-end servers that can work with Windows within 120 days. The financial penalty is the highest levied by the EU executive against a company. The Seattle-based company, denying that it abuses its overwhelming dominance to illegally crush competitors, has already vowed to appeal the verdict at the European Court of Justice. Monti said the sanctions laid down a clear marker for the future conduct of Microsoft, which escaped fines in a US anti-trust investigation.