Microsoft, Yahoo and Time Warner are among the big internet players fighting patent infringement claims brought against them by a little-known software company.
The company, Teknowledge, is also suing Akamai Technologies, Cable & Wireless Internet Services and Yahoo subsidiary Inktomi.
Teknowledge charges that online alert services offered by Microsoft, Yahoo and AOL, as well as caching services offered by Akamai, C&W and Inktomi, infringe on a US patent 6,029,175 awarded to it in February 2002 and covers "automatic retrieval of changed files by a network software agent".
The company is seeking royalty payments and unspecified damages from the internet giants.
All of the defendants have denied Teknowledge's infringement claims and charge that the patent is invalid and, therefore, unenforceable.
Microsoft filed a counterclaim earlier this week accusing Teknowledge of violating two of its own patents, one related to electronic bill payment and the other to information aggregation. Microsoft is seeking injunctions and damages.
Teknowledge first filed suit against Akamai, C&W and Inktomi in August 2002. Almost a year later, it sued Microsoft, Yahoo and Time Warner (then AOL Time Warner) The suits were merged in December.
A hearing in the case is scheduled for 28 June and a jury trial has been scheduled for 22 August 2005.
Joris Evers writes for IDG News Service