Microsoft is pursuing five alleged UK-based cybersquatters in its battle against firms and individuals who have registered variations or misspellings of its key brands, such as Xbox.
Cybersquatting is on the rise, say experts
It is already pursuing hundreds of lawsuits in the US and is now keen to extend its reach in Europe.
It marks a toughening in the way the software giant deals with the issue of cybersquatting.
It is also calling for a tightening in the way domain names are registered.
A landmark case, settled at the end of last year, saw Microsoft pick up £25,000 from the UK-based Dyslexic Domain Company. It was the first time Microsoft had claimed back not just the domain name but the profits made from using it.
According to Microsoft, Dyslexic had registered more than 6,000 domain names.
There are rich rewards for cybersquatters. Many link to lucrative Google-style pay-per-click advertising while others sell the domain names on for a profit.
"These sites confuse visitors who are trying to reach genuine company websites, which can negatively affect corporate brands and reputations as well as impair the end-users' experience online," said Aaron Kornblum, a senior lawyer with Microsoft.
"With every ad hyperlink clicked, a registrant or ad network harvests cash at the trademark owner's expense," he said.
According to Microsoft, an average of 2,000 domain names containing its trademarks are registered each day, three-quarters of which it believes are owned by professional domain name speculators.
In the past six months it has reclaimed 1,100 infringing domain names but it does not believe it is fighting a losing battle.
"We are not losing the battle. We need other brand owners to use the same tactics as us and the system of registration where there are currently lots of loopholes needs to be addressed," said Jean-Christophe Le Toquin, a lawyer with Microsoft.
The issue is currently being looked at by the World Intellectual Property Organisation (WIPO). It has found that incidents of cybersquatting have grown by 25% in the last year.
Domain names that have been snatched from under Microsoft's nose include www.exbox.com, www.windowsexp.com and winowslivemessenger.com.
Bill Gate's address www.billgates.com was cybersquatted by an individual in Florida and in 2004, a 17-year-old Canadian felt the full wrath of Microsoft's lawyers when he registered the domain name mikerowesoft.com as a joke.
Some think Microsoft faces an uphill battle in its fight against cybersquatters.
"The internet is fertile ground for domain name speculators and there are a number of professional organisations out there making a fortune out of registering variation and misspellings of popular brand names - especially Microsoft," said Jonathan Robinson, chief operating officer of NetNames, a company which manages domain names in the UK.
"Recovery of a domain name is much more difficult and costly than having secured it in the first place and Microsoft will undoubtedly find itself paying some very costly legal bills as it attempts to combat the growing problem of cybersquatting," he said.