Cisco Bid to Ax Second Email Security Patent Fails at Tribunal

Cisco Systems Inc. lost a bid Monday to throw out a competitor’s patent for email security systems when an administrative tribunal upheld the invalidity of the second of two patents asserted against it in a federal district court infringement case.

The Patent Trial and Appeal Board dismissed all claims challenging the validity of US Patent No. 8,234,705, which covers detecting and isolating network threats. Hewlett Packard Enterprise Co. and Forescout Technologies Inc. previously filed their own validity challenges against the patent that were added to Cisco’s challenge.

Patent holding company K.Mirza sued Cisco in late 2020, accusing the tech ...