Infringement - Validity of patent - Novelty - Obviousness

MMI Research Ltd v Cellxion Ltd and others: Court of Appeal, Civil Division (Lord Justices Elias, Kitchin and Sir Robin Jacob): 24 January 2012

The claimant company was an exclusive licensee under a patent EP (UK) 1 051 053, (the patent) in relation to 'IMSI catchers'; devices used by the police and security services to discover the mobile phone numbers of suspected criminals or terrorists. The IMSI catcher created a false base station, which a mobile phone communicated with. The IMSI catcher of the patent worked so successfully because it was able quickly to capture the IMSI of the mobile phone when it moved from one location area code (LAC) to another.

Claim 1 of the patent described it as 'a method for identifying a mobile telephone (MS) in a public digital cellular mobile telephony network' (see [10] of the judgment). The claimant brought an action against the first to fourth defendants on the basis that the patent was valid and had been infringed by the first defendant's product (the original trial). The defendants ran a multiplicity of attacks on the patent. One of the attacks was that the patent was invalid for lack of novelty or obviousness over the prior sale of the fifth defendant's own GA-900 machine.

The principal issue in the case was whether the idea of providing a different LAC to catch the IMSI was obvious or not, given that the principle of the fake base station was known. Another obviousness attack was obviousness over a short article by Dirk Fox (Fox) published in September 1997 about a year-and-a-half before the priority date of the patent. In the first judgment (see [2009] All ER (D) 124 (Mar)), it was held that the patent was valid, did not infringe, and not obvious in the light of Fox or the GA-900 machine (see [53] of the judgment).

Following that judgment, an application was made to the Court of Appeal to admit fresh evidence concerning the prior sales of the GA-900. That was admitted and particular, tightly defined, issues were remitted to the judge to determine (the second trial).

Those formed the subject of a second judgment. In the second judgment (see [2011] All ER (D) 82 (Mar)), which involved the consideration of fresh evidence which, it was alleged, undermined the judge's original decision, it was held that the patent was valid and was unaffected by the fresh evidence. Thus both judgments were concerned with the allegation of lack of novelty by reason of the prior sales of the GA-900. The defendants appealed aspects of both judgments.

The defendants sought to rely upon the evidence given at the second trial to challenge the judge’s findings at the original trial that it had not been established that the sale of a GA-900 machine would have enabled a user of the machine to discover how it worked and, in particular, whether it would have constituted an enabling disclosure of the invention. They also contended that in that first trial, the judge had applied the wrong test of enabling disclosure. It was also contended that the judge had made an error of principal in the way he had dealt with obviousness over Fox; the error was that the judge had overlooked the fact that the experts on both sides had accepted that the way to get from Fox to the claim would have been obvious.

The court ruled: (1) In the instant case, it could not be said that the judge had applied the wrong test. On the evidence, the judge had no alternative but to find that it had not been established on the evidence before him that the relevant features of the GA-900 would be apparent to a purchaser from the machine or from its instruction manual. Therefore, the challenges to the decision of the judge at the original trial on the issue of disclosure by the GA-900 and any associated documentation would be rejected as would the challenges to his decision at the second trial on the remitted issues (see [39], [44] of the judgment).

The appeal from the first judgment concerned with the allegation of lack of novelty arising from the prior sales and the appeal from the second judgment failed (see [45] of the judgment).

(2) In the instant case, the reasons the judge gave for rejecting the case for obviousness over Fox had overlooked the concessions made by the experts that claim 1 would occur to the skilled team on reading Fox (see [70], [72] of the judgment). The appeal would be allowed on the basis that the patent was invalid for obviousness over Fox (see [79] of the judgment).

Decisions of Floyd J [2009] All ER (D) 124 (Mar); and; [2011] All ER (D) 82 (Mar) reversed in part.

Martin Howe QC and Henry Ward (instructed by Charles Russell LLP) for the claimant; Alastair Wilson QC and Simon Malynicz (instructed by Addleshaw Goddard LLP) for the defendants.