Comcast Sues U.K.'s BT Seeking To Invalidate Patents

Comcast filed a lawsuit in U.S. federal court against BT Group seeking to invalidate eight of the telco's patents, which the British company has accused Cox Communications and Cable One of infringing.

The MSO filed the complaint seeking declaratory judgment on the validity of the BT patents Tuesday in the U.S. District Court for the District of Delaware.

Last year BT filed suit against Cox and Cable One for infringement of BT patents, including those relating to the DOCSIS cable standard, cable network billing, the use of secure cards for service access and multiservice networks. BT recently asked the court to add Comcast to the suit.

Comcast declined to comment.

A BT spokesman said in an e-mailed statement, "We believe there is a strong case of infringement, so this is why we have acted... BT's constant investment in innovation has seen it develop a large portfolio of patents which are corporate assets, so it is only right that we are seeking to protect that investment."

The Comcast lawsuit is docket no. 11-CV-843 in the Delaware federal court.

The eight BT patents that Comcast is contesting are U.S. Patent Nos.: 

* 5,142,532 ("Communication System");

* 5,526,350 ("Communication Network With Bandwidth Managers for Allocating Bandwidth to Different Types of Traffic");

* 6,538,989 ("Packet Network");

* 6,665,264 ("Connection Admission Control for Connection Oriented Networks");

* 5,790,643 ("Pricing Method for Telecommunication System");

* 5,923,247 ("Fault Monitoring");

* 6,205,216 ("Apparatus and Method for Inter-Network Communication"); and

* 6,473,742 ("Reception Apparatus for Authenticated Access to Coded Broadcast Signals").