Northeastern University in the US filed its claim for damages and royalty payments last year, and Google has now counterclaimed saying the patent in question should be made invalid because of prior art.
The patent in dispute describes a distributed database system that breaks queries into fragments and distributes them to multiple computers in a network, to get faster search results.
Northeastern University claims Google uses this system to power its search engine.
The claim says Kenneth Baclawski, an associate professor at Northeastern, invented the system, and that the system is licensed exclusively to search technology firm Jarg. Baclawski is a founder of Jarg.