Adaptive Spectrum And Signal Alignment Inc v British Telecommunications Plc

A patent claim requiring a profile state transition matrix is concerned with how the system operates, not merely with whether it produces equivalent outputs. The matrix must be implemented in hardware or software and its indicated information must have a causal role in evaluating and selecting the target profile. The claim does not prescribe the timing or particular method by which the matrix is consulted. Replacing a loop with an equation does not avoid infringement where the equation depends on, and preserves, the priority information represented by an implemented matrix. A party is not automatically barred from advancing a point later merely because it could have been raised earlier. Abuse of process requires a broad merits-based assessment.

British Telecommunications plc sought a declaration that its changed broadband access system did not infringe ASSIA’s EP (UK) 1,869,790 patent. The original system had been held to infringe at trial in [2013] EWHC 3768 (Pat), and the Court of Appeal had dismissed BT’s appeal concerning that patent in [2014] EWCA Civ 1462.

BT replaced loop software used to select a target line profile with equations. ASSIA alleged that the changed NGA Equation system still used the Service Profile Table as a profile state transition matrix and therefore infringed claims 1 and 13. BT also proposed a further modification and raised abuse-of-process objections to ASSIA’s infringement case and to any renewed validity challenge.

1. Infringement of the NGA Equation system. The Service Profile Table was an implemented profile state transition matrix. It identified possible transitions and their priorities through the cap-level numbers and the rows representing profiles. The relevant information was used by the system, even though the table was consulted at the final stage and the equation calculated the relevant cap level before the profile was selected.
2. The claim imposed no additional requirement that the matrix itself be used at a particular stage, or that the software work through its rows. It required a causal relationship between the information indicated by the matrix and the achievement of the result. The equation operated precisely because the ranking embodied in the Service Profile Table was maintained. Replacing the loop with the equation therefore made no difference to infringement.
3. The presence of interleaving did not defeat infringement. The relevant cap-level transitions with the same interleaving level were possible transitions whose priority was indicated by the cap-level number. The system need only use the invention for some transitions. The corresponding conclusion applied to the relevant red logic, although it was unnecessary to examine that logic in detail.
4. Proposed Further NGA Equation system. The proposed replacement would still leave a plurality of threshold tables. The upstream Cap Level table contained values used in inequalities and was therefore a threshold table. The further system would consequently continue to satisfy feature (h).
5. Abuse of process. The principles in Chiron v Organon (No 14) [1996] FSR 701 and Johnson v Gore Wood [2002] 2 AC 1 did not make a point abusive merely because it could have been raised earlier. The issue required a broad merits-based assessment. ASSIA’s case concerned a different changed system, and there was no good reason to prevent it from advancing the infringement case or to permit BT to challenge validity again.
6. The NGA Equation system infringed claim 1, and the Proposed Further NGA Equation system would also infringe. BT’s application for a declaration of non-infringement therefore failed.

• Court of Appeal: The appeal concerning infringement of the patent was dismissed: [2014] EWCA Civ 1462.
• High Court (Patents Court): The original NGA system was held to infringe the patent: [2013] EWHC 3768 (Pat). The present judgment determined infringement by the changed and proposed systems.