Judge Blocks Microsoft Feature

A federal judge Wednesday temporarily blocked Microsoft Corp. from using a networking feature in future versions of its Windows operating system.

U.S. District Judge Jeffrey White in San Francisco forbade Microsoft from selling or marketing its Chimney design while a lawsuit over a patent owned by Alacritech Inc. was pending, closely held Alacritech said in a statement.

Chimney is slated to be used in the Longhorn version of the Windows operating system scheduled for release late next year and in other Microsoft server software. Windows is Redmond, Wash.-based Microsoft’s most profitable product.

“Microsoft rejected licensing terms that would be acceptable to us,” said Larry Boucher, chief executive of San Jose-based Alacritech. “We were forced to sue Microsoft to stop them from continuing to infringe, and inducing others to infringe, on our intellectual property rights.”

Microsoft spokeswoman Stacy Drake said the company’s Chimney technology was “independently developed by Microsoft engineers.” Because the Longhorn operating system won’t be released until next year, she said, the lawsuit will have “no immediate customer impact.”

Drake said she was unsure whether other software using Chimney had been released.

“As an intellectual property company we invest heavily in research and development and are committed to respecting the intellectual property rights of others,” Drake said.

In its statement, Alacritech said Microsoft infringed its SLIC technology, patented in 2001, which is intended to eliminate processing bottlenecks in computer networks.

Each company says its product will let networks serve a larger number of users or programs without breaking down or requiring significant changes in procedure.

Alacritech spokesman Joe Gervais didn’t return a call seeking comment.

Shares of Microsoft fell 28 cents to $25.04 on Nasdaq.