Adaptive Spectrum and Signal Alignment Inc v British Telecommunications Plc

Patent claims are construed in their context without adding limitations that the words do not contain. “Generating” a parameter set may nevertheless require creating a bespoke set rather than selecting an existing profile. Current and historical data are assessed when collected. A claim requiring a profile state transition matrix requires an actual identifiable matrix; mathematical equivalence or reverse engineering is insufficient. A system need not assess lower-priority profiles once a higher-priority feasible profile has been identified. The 495 patent was valid but not infringed. The 790 patent was valid and infringed by the NGA system.

ASSIA alleged that BT’s Dynamic Line Management systems infringed claims of two UK patents concerning adaptive management of DSL operating parameters and selection of DSL line profiles. BT denied infringement and challenged validity on novelty and obviousness grounds.

The action concerned BT’s 20CN, 21CN and NGA networks. The 495 patent was challenged by Hendrichs, Rahamim and Kerpez. The 790 patent was challenged by Hendrichs and Gross. The central issues were claim construction, infringement, novelty and obviousness.

1. 495 patent. “Controller” was an ordinary word and did not require physical or logical separation from the modem. Current and historical data were assessed at collection. “Generating” meant creating a bespoke parameter set, not selecting an existing set of stored profiles. Margin-related parameters could be configuration or transmission parameters.
2. BT’s systems selected pre-existing profiles and therefore did not generate the required parameter set. None infringed the 495 patent. Hendrichs did not collect both current and historical data within the claim, and its stored-profile selection did not amount to generation. The claim was novel. Hendrichs and Rahamim did not make it obvious because the skilled person had no reason to retrieve stored MIB data. Kerpez made claim 1 obvious on the wider construction of “generating”, but claim 6 remained non-obvious. The patent was valid.
3. 790 patent. A line profile meant a set of configuration parameters. The DSL controller was distinct from the modem pair. A profile state transition matrix had to be actually identifiable in the hardware or software; equivalent logic derived by reverse engineering was insufficient. “A plurality of target line profiles” could cover a subset of possible transitions. Feasibility testing of every lower-priority profile was unnecessary where a higher-priority feasible profile had been identified.
4. The NGA profile cap level table constituted a profile state transition matrix for the profiles it addressed. Its loop assessed feasibility, used threshold tables and rules, and used the calculated safe rate as estimated data. The NGA system infringed claims 1, 10 and 13. Hendrichs and Gross did not render the claims obvious.
5. The 495 patent was valid but not infringed. The 790 patent was valid and infringed by BT’s NGA system.