Software giant Microsoft Corporation filed or amended four civil suits in the United States and launched five new cases in Britain against cybersquatters, who register Internet site names in the hope of a quick buck. The sites are typically loaded with "pay-per-click" advertisements that generate revenues for the domain owner, who also often try to sell the names back to legitimate companies to remove their irritant value. Microsoft said that in the past six months, it had already reclaimed more than 1,100 domain names worldwide that infringed on its trademarks. "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. With every ad hyperlink clicked, a registrant or ad network harvests cash at the trademark owner"s expense, while derailing legitimate efforts by computer users who are trying to go to a specific website," said Aaron Kornblum, senior attorney with Microsoft.