Balloons and oxymorons -- the Lords' decision

Further to this morning's earlier posts (see immediately below), the IPKat can now say a bit about the approach taken by the House of Lords to the proper test of inventive step in Conor Medsystems Inc v Angiotech Pharmaceuticals Inc. The facts, taken from the judgment of the trial judge, were as follows. Angiotech owned a European patent designating the UK for a stent used in coronary angioplasty. the basic idea of a stent is that, when it is inserted into a diseased artery in the course of angioplasty, a little balloon can be inflated which keeps the artery open.

Right: the humble balloon was part of the prior art -- they work best with taxol, though

Angiotech's patent claimed a stent coated with a polymer which was loaded with the drug taxol: this inhibited the development of tissue that might result in the gradual closure of the artery (a condition known as restenosis). Angiotech licensed the patent to Boston Scientific, which made stents. Conor, a competitor of Boston Scientific, sought to revoke the patent, claiming that it was obvious in the light of the prior art.

Pumfrey J allowed the application and revoked the patent. The mere fact that no-one had used stents like this before might make them new, but it didn't make them non-obvious. Given the state of the art, it was obvious to anyone who needed a stent of this nature that he would have to use taxol. Accordingly, in his view, the patent was invalid for obviousness. The Court of Appeal, for whom Lord Justice Jacob delivered the judgment, dismissed Angiotech's appeal.

Today the House of Lords took a different view, allowing the appeal and affirming the validity of Angiotech's patent. The opinion of their Lordships is contained in the speech of Lord Hoffmann, to whose words Lord Walker of Gestinthorpe could add nothing useful. Lord Hoffmann said as follows:

"2. Since the decision of the Court of Appeal, Angiotech and Conor have reached a settlement. Conor does not oppose Angiotech’s appeal. But a patent confers proprietary rights in rem and the validity of a patent cannot be established simply by a judgment in default of opposition. Your Lordships therefore invited the Comptroller General of Patents to assist the court in presenting what appeared to him to be the arguments against the validity of the patent. ...

3. There is still no European Patent Court. A European patent takes effect as a bundle of national patents over which the national courts have jurisdiction. It is therefore inevitable that they will occasionally give inconsistent decisions about the same patent. ... Sometimes one is dealing with questions of degree over which judges may legitimately differ. ... In this case ... there is a question of principle at stake. It is about how you identify the concept embodied in the invention which may constitute the “inventive step” for the purposes of article 56 of the EPC and section 1(1)(b) of the Patents Act 1977. ...

12. The Angiotech stent has been a great commercial success. It has the largest share of the market in drug eluting stents, which have very considerably reduced the incidence of restenosis.

17. ... It is the claimed invention which has to involve an inventive step. The invention means prima facie that specified in the claim: .... In the present case, the invention specified in claim 12 was a stent coated with taxol. There was no dispute that this was a new product. The question should therefore simply have been whether it involved an inventive step. As in the case of many product claims, there was nothing inventive in discovering how to make the product. The alleged inventiveness lay in the claim that the product would have a particular property, namely, to prevent or treat restenosis. ... So the question of obviousness was whether it was obvious to use a taxol-coated stent for this purpose. And this, as I have said, was the question to which the experts addressed themselves.

18. [Counsel for Conor] sought to avoid this question by watering down the claimed invention by reference to what he said were inadequacies in the specification. It did not contain information about human or animal tests which showed that it would work or provide enough information about doses and so forth to enable the skilled person to work it. It was therefore nothing more than an idea that taxol might work and any skilled person would have known that.

19. In my opinion, ... the invention is the product specified in a claim and the patentee is entitled to have the question of obviousness determined by reference to his claim and not to some vague paraphrase based upon the extent of his disclosure in the description. ...

28. The question was whether that was obvious and not whether it was obvious that taxol (among many other products) might have this effect. It is hard to see how the notion that something is worth trying or might have some effect can be described as an invention in respect of which anyone would be entitled to a monopoly.

Left: is this truly an oxymoron--or is it merely two individual contradictory statements?

It is therefore perhaps not surprising that the test for obviousness which Pumfrey J devised for such an “invention” was whether it was obvious to try it without any expectation of success. This oxymoronic concept has, so far as I know, no precedent in the law of patents. ...

37. The Court of Appeal upheld the judgment of Pumfrey J on the ground that the patent contained no “disclosure” saying that taxol was specially suitable for preventing restenosis. .... But there is in my opinion no reason as a matter of principle why, if a specification passes the threshold test of disclosing enough to make the invention plausible, the question of obviousness should be subject to a different test according to the amount of evidence which the patentee presents to justify a conclusion that his patent will work. ...

40. In the event, ... neither the judge nor the Court of Appeal answered what I consider to have been the correct question, namely, whether it was obvious to use a taxol-coated stent to prevent restenosis. ...

42. In the Court of Appeal, Jacob LJ dealt comprehensively with the question of when an invention could be considered obvious on the ground that it was obvious to try. ...

43. But Jacob LJ rejected this approach ... because “the patent has not in any way demonstrated that taxol actually works to prevent restenosis.” I agree with the Dutch court that patent law does not require such a demonstration. It was not a sufficient reason for not applying the ordinary principles of obviousness to the claimed invention. I would therefore allow the appeal".

It seems to the IPKat that Lord Hoffmann has sought to claw back the test of inventive step from the jaws of analytical oversophistication and to bring it back to basics. "Obvious to try" is a valuable tool for enabling patent lawyers to gauge the degree (if any) of inventive step in a patented invention, but it is only a means -- and not even an exclusive means, at that -- of assisting the court to reach a conclusion.

Right: this is how arteries get furred up ...

He also speculates whether his Lordship's comment at para. 12, relating to the patented product's great commercial success, throws a significant ray of light on Lord Hoffmann's thought-processes; in its day, "commercial success" was often a carefully deployed argument in favour of a patent's non-obvious nature. But the reality is that the test of inventive step is one that applies to the invention as patented, as embodied in its claims, not by the success or failure in the marketplace of any manufactured product which incorporates its functions. Merpel says, is that the sound of Champagne corks I hear from the celebrating Angiotech -- or is it the popping of stents?