Patents: the Difficulties of Designing Around a Patent: Adaptive Spectrum and Signal Alignment Inc v British Telecommunications Plc #2

In Adaptive Spectrum and Signal Alignment Inc v British Telecommunications Plc [2013] EWHC 3768 (Pat) (3 Dec 2013) the claimant sued the defendant telecommunications company for infringing two of its European patents:

• EP 2,259,495 adaptive DSL margin and band control using historical operational data ("495"); and
• EP 1,869,790 DSL state and line profile control ("790").

Mr Justice Birss held that 495 was valid but had not been infringed and that 790 was valid and had been infringed. Both sides appealed to the Court of Appeal. In Adaptive Spectrum and Signal Alignment Inc v British Telecommunications Plc [2014] EWCA Civ 1462 (11 Nov 2014) the Court of Appeal allowed the claimant's appeal against the finding of non-infringement of 495 and dismissed the defendant's appeal against the finding of infringement of 790.

Following Mr Justice Birss's judgment BT attempted a redesign by replacing  loop software with an equation. BT argued that that was enough to take its system outside claims 1 and 13 of 790. The claimant disagreed and argued that the equation operated in exactly the same way as had been claimed. BT applied for a declaration of non-infringement under s.71 of the Patents Act 1977. The judge gave directions for the resolution of the issue. It came before him as Adaptive Spectrum And Signal Alignment Inc v British Telecommunications Plc #2 [2014] EWHC 4194 (Pat) (18 Dec 2014). BT also proposed some further modifications arguing that even if its equation system infringed the further modified system would not. His Lordship therefore had two issues to determine, namely whether the original redesigned system infringed the patent and if it did whether the further redesigned system did so also.

The judge found for the claimant on both issues. 

As to the original redesign his Lordship held that the only difference between the original and the redesigned system was that a loop was replaced by an equation. The point of the loop was to find a profile with a maximum rate above but closest to the safe rate. The equation achieved that directly.  He explained at para [79]:

"Standing back it seems to me that the NGA Equation system infringes claim 1. In the circumstances considered at trial, such as using the green downstream logic, the NGA Equation system, like the original NGA system itself, operates by having isolated out from the overall set of all profiles in which a line is capable of operating, a set of possible profiles ranked by priorities which exist independently of line conditions and then choosing from that set the highest priority feasible profile. The other aspects of the claim concerning feasibility (sub-rules etc.) are satisfied. The process works as a whole because for a given starting profile the possible profile transitions and the priorities are indicated in the Service Profile Table. That table is a profile state transition matrix. The final profile is selected from that matrix. The fact an equation is used instead of a loop makes no difference, the NGA Equation system infringes claim 1 just the same."

 Similarly the judge was not persuaded that the further redesign availed BT because it also included a threshold table. As the claimant relied on the use of threshold tables in the non-infringement proceedings but not in the original proceedings BT argued that it was barred from raising the new point by the rule in Henderson v. Henderson (1843) 3 Hare 100 as amplified by the House of Lords in Johnson v. Gore Wood & Co. [2000] UKHL 65; [2001] 1 All ER 481; [2001] 2 WLR 72 (14 Dec 2000). Mr Justice Birss was having none of that. There was simply no reason for the claimant to refer to the threshold table. As the judge observed at [93]:

"The crucial point is that the system alleged to infringe at trial was one thing whereas the system being considered now is another different one."

He added:

"ASSIA established that the original NGA system infringed. That was not a warrant that a different system did not. If the infringement case at trial had been concerned only with distinct and clearly separable adjunct to the NGA system and, after a finding of infringement by that adjunct, the defendant removed it, then I can see that a defendant in such a case might have grounds to complain about abuse of process if the patentee turned round and said for the first time - oh well the system without the adjunct still infringes. But that is a long way from the facts of this case."

That must surely be right.

As there was no dispute that the claims should be construed in accordance with the principles established by the House of Lords in Kirin-Amgen Inc and Others  v Hoechst Marion Roussel Ltd and Others [2005] RPC 9, [2004] UKHL 46, [2005] 1 All ER 667, (2005) 28(7) IPD 28049, [2005] RPC 169 and the Court of Appeal in Virgin Atlantic Airways Ltd v Premium Aircraft Interiors UK Ltd [2009] EWCA Civ 1062, [2010] RPC 8 the case hung on the construction of the claims and its own facts. Consequently, the only issue for which this case may be remembered is the issue estoppel point and even then it is hard to argue that it made new law.

I decided to discuss this case because of the maths.  If anyone is similarly interested he or she should call me on 020 7404 5252 during office hours or send me a message through my contact form.