[Festo and] The Doctrine of Equivalents

The UK House of Lords' decision in Kirin-Amgen Inc and others v Hoechst Marion Roussel Limited and others[2004] UKHL 46 makes a pointed observation about the current state of the U.S. Doctrine of Equivalents.

Since the Catnic case we have article 69 [of the European Patent Convention] which, as it seems to me, firmly shuts the door on any doctrine which extends protection outside the claims. I cannot say that I am sorry because the Festo litigation suggests, with all respect to the courts of the United States, that American patent litigants pay dearly for results which are no more just or predictable than could be achieved by simply reading the claims.With regard to the scope of EPC Article 69, Lord Hoffman goes on to write that that Although the EPC thus adopted the United Kingdom principle of using the claims to determine the extent of protection, the Contracting States were unwilling to accept what were understood to be the principles of construction which UnitedKingdom courts applied in deciding what the claims meant. These principles, which I shall explain in greater detail in a moment, were perceived as having sometimes resulted in claims being given an unduly narrow and literal construction. The Contracting Parties wanted to make it clear that legal technicalities of this kind should be rejected. On the other hand, it was accepted that countries which had previously looked to the "essence of the invention" rather than the actual terms of the claims should not carry on exactly as before under the guise of giving the claims a generous interpretation.

This compromise was given effect by the "Protocol on the Interpretation of Article 69":
"Article 69 should not be interpreted in the sense that the extent of the protection conferred by a European patent is to be understood as that defined by the strict, literal meaning of the wording used in the claims, the description and drawings being employed only for the purpose of resolving an ambiguity found in the claims. Neither should it be interpreted in the sense that the claims serve only as a guideline and that the actual protection conferred may extend to what, from a consideration of the description and drawings by a person skilled in the art, the patentee has contemplated. On the contrary, it is to be interpreted as defining a position between these extremes which combines a fair protection for the patentee with a reasonable degree of certainty for third parties."

It used to be thought that despite article 69 and the Protocol, there remained serious differences between the approaches to construction of the United Kingdom on the one hand and Germany and the Netherlands on the other. And it is true that in the early years of the EPC, there was a view in the German and Netherlands courts that the Convention had made no difference and that the Protocol entitled the courts of Contracting States to go on deciding the extent of protection exactly as before. The highest courts in both Germany and the Netherlands have said that the effect of article 69 is to give the claims what the European Patent Office has called a "central role."A more-detailed story from "The IPKat marvels at Lord Hoffmann's clarity of thought and lucidity of expression. Does anyone in the UK seriously advocate exchanging this sort of quality for an unknown and untried Community patent court?"

Rodney D. Ryder