Armour v LeisureTech

On Friday 14 November, Mr Justice Arnold delivered his judgment in Armour Group Plc v Leisuretech Electronics Pty Ltd [2008] EWHC 2797 (now available from BAILII here). The case related to Leisuretech's European patent EP1004222 (not EP1004221 as stated in the judgment) for a distributed stereo system. Leisuretech claimed that Armour were infringing their patent, and Armour in turn sought revocation of the patent on the ground that the claimed invention was obvious.

The claimed invention covered a distributed stereo audio system in which a particular type of signal cable known as 'Cat5' (no feline connotations) was used for both audio and power connections. In the distributed audio system (as shown in the figure, right), a cable (11) was used to connect both a signal source (5) and power supply (10) to an amplifier (4), different pairs of the cable being used for left and right audio signals and for a DC power supply from the power supply to the amplifier.

Much detail regarding the state of the art at the 1997 priority date of the patent was gone into, helped by expert witnesses from both sides. Through this, it was established that Cat5 cables were fairly commonplace in the field at the time. They were generally used for transmission of audio and control signals, but not usually for supplying DC power, largely due to the resistive losses inherent in such cables.

It was, however, well known that Cat5 cables could carry small amounts of power, and there were certain integrated circuit (IC) amplifiers widely available at the time that would at least work with these power levels. Even though these would not be regarded as 'hi-fi' amplifiers, Arnold J considered that relevant segments of the market did not necessarily require more than "basic hi-fi quality" (an oxymoron?).

Arnold J found that it was obvious to arrive at the invention from any one of three starting points: i) starting with the known amplifiers, Cat5 cables would be an obvious choice to use for supplying power; ii) starting with the cable, IC amplifiers would be an obvious choice given the low power capability; or iii) starting with the known system architecture, an IC amplifier and Cat5 cables would be obvious choices to make. The patent was therefore found to be invalid and ordered to be revoked.

(below: cat 5 is special)

The IPKat notes that this case proved to be quite a test for the Windsurfing/Pozzoli approach on inventive step, which has to be applied quite carefully for alleged inventions having a combination of features that might or might not be arrived at through a combination of apparently obvious steps. He wonders if it might have been more straightforward to use the EPO problem-solution approach instead, which might have made easier work of assessing the different non-inventive steps taken to arrive at the claimed invention by simply seeing each of them as small problems with clearly obvious solutions. Could this have been done, or would it have been sacreligious?
Armour v LeisureTech Armour v LeisureTech Reviewed by David Pearce on Monday, November 17, 2008 Rating: 5


  1. David, I'm trying to be first in here: so this written submission is offered before I've even read the decision. I'm in Munich so I have a one hour headstart on other readers. You ask a nice question but can you clarify, please. Are you musing on the judge using PSA or, rather, counsel for the petitioner for revocation? In the last two years it's my wishful thinking, that the English judges have been anticipating the arrival in England (either washing up the estuaries or debauching from the offices of patent attorneys) of EPO PSA and so have thoughtfully been writing obviousness decisions to be compatible with EPO PSA. But there's a tacit understanding throughout the English patent litigation community not to refer to EPO PSA, isn't there? I see it (but then from my look-out point in Munich I would, wouldn't I?) as the "elephant in the room". Seems to me that English judges can't operate PSA till it's pleaded, and it isn't pleaded because counsel and instructing solicitors imagine that running a PSA attack would have adverse consequences. So, readers, do English litigators have cold feet, and can English judges invoke EPO PSA in their decisions off their own bat, or must they first wait till some litigation team is bold (or foolhardy) enough to make it the basis of their petition for revocation?

  2. I am merely faintly suggesting that the problem-solution approach might have been worth a try in this case. I can't imagine an English court using it alone, but it would be nice to see it used at least in parallel to show how it would arrive at the same result.

  3. Nice for me David, indeed. And nice for you too. Probably nice for lots of people. But perhaps not so nice for the client who has to pay for every lawyer hour. All the same, if we assume that only 50/50 cases go to trial, but you are one of those, and you are going to trial, and PSA does support the argument you are making, well then running it out before the judge might just tip the balance, and so worth a great many lawyer hours. Perhaps.

  4. I see that, in the EPO, the Opposition Division has not yet summonsed the parties to oral proceedings. The Primary Examiner now has additional material to help the approach to a preliminary view to append to the Summons. I am fascinated to read what will be in that annex. Since the EPO bases itself on prior publications but the English High Court on witness testimony, there is plenty of scope for a quite different "take" on the evidence adduced in the two fora. Common law vs civil law. Will the EPO uphold the claims, eventually? Will Leisuretech, like Angiotech with its TAXOL stent, successfully appeal the adverse ruling in the High Court?

  5. Re the Roy March comment regarding an English litigation team having the gumption to have a crack at running problem and solution before an English patents court judge. This was tried back in 2005 in the Ranbaxy v Warner Lambert case. Pumfrey was having none of it: "There are two possible difficulties with this approach (there may be as many, or more, with Windsurfing, I do not know). The first is its concentration on the closest prior art, which must stem from a belief that if an invention is not obvious in the light of the closest prior art it cannot be obvious in the light of anything further away. This runs the risk of offending against the principle that a skilled man must be permitted to do that which is obvious in the light of each individual item of prior art seen in the light of the common general knowledge. There is an illustration of this risk in the present case. The second is that the reformulation of the problem can obscure that which is objectively obvious. But as stated, I cannot see this approach producing a different result from that produced by a Windsurfing analysis in the vast majority of cases. Where results differ, I suspect that it is because of the importance that a judge following the Windsurfing approach will give to the common general knowledge." Following that, all practicioners were waiting to see what Jacob et al would make of this on appeal. Unfortunately for the sake of English jurisprudence, the point did not go on appeal. The position we are now left with is some post Windsurfing / Pozzoli test with an Angiotech House of Lords twist, which in effect only goes as far as approving what Kitchin said in Generics v Lundbeck at first instance without giving some other statement of the law. The only step forward that Angiotech gives over Windsurfing / Pozzoli is the inclusion of an assessment of motivation of the skilled man to make the step from the prior art to the invention, which is a step towards problem and solution. It's a shame that Angiotech at the House of Lords did not grasp the nettle and give some clarity, but we are where we are.

  6. Thanks for that. Yes, a shame. Lord Hoffmann and Jacob LJ have both shown themselves capable of recognising when EPO caselaw is "settled". I don't know anything that has become more settled over the last 30 years than the Problem and Solution Approach to obviousnness. But, then again, I can't think of any other topic in patent law where so many people say they understand it, but then go and make some statement which reveals that they don't understand it at all. Bit like "technical character" maybe. In other words, for an Appeal Court Judge, to invoke EPO jurisprudence does involve a degree of risk.


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