Although Microsoft registered the Web site for its new Windows Azure more than 14 years ago, it has not trademarked the name of its new cloud-based operating system, Windows Azure, Internet searches revealed Monday.

According to searches conducted by Computerworld, Microsoft has not applied for a trademark for either "Windows Azure" or "Azure Services Platform" with the US Patent and Trademark Office. Microsoft used both names to describe its software-plus-services technology.

Microsoft's own trademark list also omits Azure, though that list has not been updated since earlier this month.

Other Microsoft technologies, including Windows Vista, DirectX, Hyper-V and Surface, however, have been trademarked by the Redmond, Wash. company.

Earlier Monday, Ray Ozzie, the company's chief software architect, unveiled Windows Azure as Microsoft's cloud-computing platform. Ozzie said that work had started on Azure just before Amazon.com launched its own Elastic Compute Cloud (EC2). The two platforms, EC2 and Azure, will likely compete for developer attention.

Microsoft will release a preview of Azure at the Professional Developers Conference (PDC), where Ozzie debuted the technology. He did not spell out when Azure would be generally available, however.

But while Windows Azure doesn't show up in the US Patent and Trademark Office's database, Microsoft more than planned ahead when it registered the "azure.com" Web site.

A search of registered sites found that Microsoft grabbed azure.com -- the site it also unveiled Monday that hosts information about the new platform -- in October 1994. The site is currently registered at GoDaddy.com, a cut-rate domain registrar that currently is running a US$9.99 per year special.

Microsoft also owns the "azure.net" domain, which it registered in November 2003.