Doctrine of Equivalents: It’s not only about asking the right questions

Case No. 4A_131/2016 (Supreme Court) ¦ Decision of 03 October 2016 ¦ “Urinalventil”

Little time? Read the summary.

I have reported on the main hearing before the FPC on this Blog here. For a brief review of the underlying decision O2014_002 of the FPC, see this Blog here.

boy-214906_960_720Long awaited, now here it is: The first decision of the Supreme Court on the Doctrine of Equivalents since ages; see fulltext below. You hoped for a ready-mix for assessment of equivalency? I’m sorry, there is none.

But let’s have a look at the very basic facts first.

The patent in suit is EP 1 579 133 B1 (embedded below), and it’s all about a non-return valve for a urinal. The independent claim reads as follows (mark-up added):

A non-return valve (3), comprising an inlet section (5) in the form of a self-supporting trough-shaped section and an outlet section, the outlet section being made of a flexible resilient material connected to the inlet section (5), whereby the outlet section comprises a flat flexible resilient strip (6) with a high inherent degree of flexibility, the strip (6) being connected with the inlet section (5) at its upper edge; and further comprising a component that is separate from the strip (6) providing a complementary surface against which the lower end of the flexible strip (6) may seal.

The technology is not difficult to understand: The strip (6) and the ‘component with a complementary surface’ — actually, yet another strip — are arranged in a way as to allow fluid passing through the valve in the one direction of the valve. The valve closes when the fluid has passed, to prevent unpleasant odor from rising up. Flattened tubes instead of separate strips had been known in the prior art for the same purpose; see D1, US 3 835 857).


The million dollar word is “separate”. What does the feature

[…] a component that is separate from the strip (6) providing a complementary surface against which the lower end of the flexible strip (6) may seal

actually mean? There is no explicit definition of “separate” in the patent. Actually, the word as such was not even used in the application as filed at all. It had been introduced during prosecution, based on the overall specification and figures which all show (completely) separate strips; see figures 1 and 2, above.

On the other hand, the two strips are interconnected by lateral connectors in the attacked embodiment. Noteworthy, this configuration is protected by EP 2 553 299 B1 of the defendant (embedded below; EP’299 explicitly acknowledges the patent in suit as closest prior art in para. [0003]-[0005]).

attacked embodiment
attacked embodiment

The assessment of the Supreme Court is straight forward — and in line with the decision of the FPC. In light of the figures, the description and in differentiation over the prior art (flattened tube) the feature is construed to imply a full-length separation. The Supreme Court explicitly holds that the embodiment with loose ends is not merely a preferred embodiment:

Die Ausführungsbeispiele weisen auf dieses Verständnis eindeutig hin, ohne dass Anhaltspunkte für ein weiteres Verständnis von ‘separate’ in dem Sinne bestehen würden, dass das Ausführungsbeispiel mit den losen Enden nur als eine – wie die Beschwerdeführerin behauptet, bevorzugte – Ausführung erschiene.

Thus, no literal infringement.


Almost no decision on equivalency is uncontroversial, and people mostly have a very firm opinion pro or contra infringement under the Doctrine of Equivalents. So do I. But I feel there are plausible arguments for both views in the present matter, and I won’t take position for either side. No use crying over spilt milk anyway; this case has been finally decided now.

But let’s have a closer look at what can be learned about how the Supreme Court nowadays assesses infringement under the Doctrine of Equivalents on the basis of the three-step questionnaire as defined by the FPC (see S2013_001).


Do the replaced features have the same objective function? (same effect / “Gleichwirkung”)

Erfüllen die ersetzten Merkmale [Austauschmerkmale] die objektiv gleiche Funktion? (Gleichwirkung)

First of all, what is the replacing feature? The Supreme Court identifies the replacing feature essentially as follows:

[…] component and the strip (6) are separate for a sufficient length to allow for a sealing effect when a fluid has passed.

The first question is a no-brainer here: Fulfilment of the same function has been beyond dispute.


Are the replaced features and their same objective function made obvious to the skilled person by the teaching of the patent? (accessibility / “Auffindbarkeit”)

Werden die ersetzten Merkmale [Austauschmerkmale] und deren objektiv gleiche Funktion dem Fachmann durch die Lehre des Patentes nahe gelegt? (Auffindbarkeit)

This question had unfortunately been left undecided by the FPC (since the third question was answered in the negative). Nevertheless, the FPC had clarified in the headnote of the underlying decision how it expects this question to be addressed; see this Blog here. This hn reads as follows:

The assessment of accessibility is not to be confused with the assessment of inventiveness. Starting point for the assessment of accessibility is not the general state of the art, but the patent in suit. Therefore it is not to be assessed whether the replaced feature is inventive in view of the state of the art. It is rather to be assessed whether, starting from the teaching of the patent in suit, it is evident for the skilled person that the replaced feature has the same effect (r.
(Clarification of the case law with respect to S2013_001, decision dated 21. März 2013)

The reasons referred to in the hn read as follows:

It is to be determined whether, once the features are replaced, the same effect is evident for the person of skill in the art when objectively assessed in consideration of the teaching of the patent.

Zu beurteilen ist, ob, wenn die Merkmale ausgetauscht sind, die Gleichwirkung für den Fachmann bei objektiver Betrachtung unter Berücksichtigung der Lehre des Patents offensichtlich ist.

According to the hn in light of the reasons, this test compares two already given situations (one with the replaced/claimed feature and another one with the replacing feature) and only then asks whether the same effect is evident. As I have outlined earlier, this really makes a big difference.

Now, this is what the Supreme Court asked (mark-up added):

[…], whether the skilled person who intends to add a fixation at the lower end of the strips instead of the loose ends will readily understand that the strips have to be separate at a length which is sufficient to achieve the effect which the patent intends to achieve.

[…], ob der Fachmann, der statt der losen Enden der Streifen am unteren Ende der Streifen eine Befestigung anbringen will, ohne weiteres erkennt, dass die Streifen auf einer hinreichenden Länge getrennt werden müssen, um die mit dem Patent angestrebte Wirkung zu erreichen.

I don’t think that this is what the FPC had in mind when drafting the hn and r. In the assessment of the FPC, there is no need at all for a skilled person intending to add a fixation. The skilled person rather only compares two given scenarios, i.e. the claimed solution and the attacked embodiment. If the same effect of these two embodiments is evident, the question is to be answered in the affirmative. Else, it’s not. Frankly speaking, I just cannot say whether the Supreme Court is supportive of this approach or not.


With due consideration of the wording of the claim in the light of the description, would the skilled person have considered the replacing features as a solution of equal value? (equal value / “Gleichwertigkeit”)

Hätte der Fachmann bei Orientierung am Anspruchswortlaut im Lichte der Beschreibung die ersetzten Merkmale [Austauschmerkmale] als gleichwertige Lösung in Betracht gezogen? (Gleichwertigkeit)

Assessment of this question by the Supreme Court in r. 6.3.2 starts with a summary of what the FPC had held, i.e. that the skilled person would not have considered the replacing features as an equivalent solution, with due consideration of the claim. Really? Is that it? I feel the FPC did more than that — and there is more to do according to the wording of the third question recited above, i.e. to give due consideration to the claim wording in view of the description. And it had been the description and the figures which strictly limited the term “separate” to only cover loose ends. Consequently, the FPC had discussed the actual meaning of the claim wording (see section of the underlying decision O2014_002):

Thus, it is not apparent for the skilled person in view of the claim construction that the claimed subject-matter (separately) could equivalently be replaced with a modification of this feature (lateral connectors).

So ist in diesem Fall für den Fachmann bei Orientierung am ausgelegten Anspruchswortlaut auch nicht erkennbar, dass die anspruchsgemässe Lehre (separat) mit einer Abwandlung des betroffenen Merkmals (Verbindungsstege) gleichwertig realisiert werden kann.

From the decision as such, it is not clear to me whether (or to which extent) the Supreme Court has paid attention to the description when answering the third question. The meaning of “separate” is interpreted more broadly again, based only on the wording of the claim as such:

Actually, a complete separation […] with loose ends is not required by the wording of the claim as such.

Eine vollständige Trennung […] mit losen Enden wird vom Anspruchswortlaut für sich genommen gerade nicht verlangt.

If that was indeed the case, then why is there no literal infringement?

The Supreme Court finally holds:

Thus, the loose end of the strips can equally be replaced by a fixation.

Danach lässt sich das lose Ende der Streifen gleichwertig durch eine Befestigung ersetzen.

In my perception, the great achievement of the third question reaches far beyond that. It had been intended to be all about providing a reasonable degree of legal certainty for third parties, i.e. to reasonably confine the potential scope under the Doctrine of Equivalents. Therefore, it essentially asks whether the skilled person would really have considered the replacing feature as an equivalent, with due consideration of the claim and the description — not merely whether it objectively is an equivalent replacement.

The Supreme Court notes in passing that the attacked embodiment has been patented (explicitly over the patent in suit as prior art), but holds that this does not change the fact that it still makes use of the patent in suit. The bottom line of the decision is a reference to a famous Swiss legal scholar:

Subsequent inventions are directly covered by the scope of the prior teaching if this prior teaching is fully embodied while providing for an improved, non-obvious variant; and inventions which make use of the core of the inventions that has been patented earlier (ALOIS TROLLER, Immaterialgüterrecht, Bd. II, 3. Aufl. 1985, S. 891). Art. 36(1) PatA provides for a non-exclusive license in such cases (cf decision 4C.502/1997 of April 20, 1998, r. 5b).

Vom Schutzbereich der älteren Lehre direkt umfasst sind spätere Erfindungen, wenn sie die ältere Lehre vollständig anwenden, aber eine verbesserte, nicht naheliegende Ausführung lehren, und ebenso Erfindungen, bei deren Anwendung der Kern der früher patentierten Erfindung mitverwendet wird (ALOIS TROLLER, Immaterialgüterrecht, Bd. II, 3. Aufl. 1985, S. 891). Dafür sieht Art. 36 Abs. 1 PatG eine nicht ausschliessliche Lizenz vor (vgl. Urteil 4C.502/1997 vom 20. April 1998 E. 5b).

Reference to Art. 36(1) PatA looks like an easy way out, but the right to be granted a non-exclusive license is explicitly only given by law if the invention represents an important technical advance of considerable economic significance in relation to the invention that is the subject-matter of the prior patent. It will not necessarily be easy to meet this precondition.

I hope we will see further decisions of the Supreme Court in the near future which provide some more guidance on the actual interpretation of the second question and how the reasonable degree of legal certainty for third parties is to be safeguarded when answering the third question. Addressing infringement under the Doctrine of Equivalents with a set of three questions that somehow resemble the questionnaires used in the U.K. and Germany surely is an achievement of harmonization. But I do not yet see much harmony in how the questions are interpreted and answered.

Reported by Martin WILMING


Case No. 4A_131/2016 (Supreme Court) ¦ Decision of 03 October 2016 ¦ “Urinalventil”

Daspaco AG ./. Von Allmen AG

Composition of the Board of the Supreme Court:

  • Dr. Christina KISS
  • Dr. Kathrin KLETT
  • Dr. Gilbert KOLLY
  • Dr. Fabienne HOHL
  • Dr. Martha NIQUILLE

Court Clerk:

  •  Dr. Christoph HURNI

Representative(s) of Appellant / Patentee:

Representative(s) of Defendant:


Download (PDF, 694KB)


Download (PDF, 303KB)


Download (PDF, 437KB)


The good news from the first decision of the Supreme Court on the Doctrine of Equivalents since ages: The third question of the FPC’s questionnaire is approved. The sad news: There is little to no guidance in the decision with respect to how the second and the third question are to be interpreted. In particular, it still remains unclear how the reasonable degree of legal certainty for third parties is to be safeguarded when answering the third question.


You liked this? And you would like to be notified of new posts? Here you go.

Print Friendly, PDF & Email

11 Replies to “Doctrine of Equivalents: It’s not only about asking the right questions”

  1. Is this for real? Then what about having a narrow definition in the specification of a per se broad term used in the claim: Anything beyond this definition could still be considered an equivalent??

    1. That’s exactly the point I wanted to make! Assume the claim requires ‘rectangular’ and the specification says i) “it is important that the angle is between 89° and 91°”; or it says ii) “as understood herein, the term ‘rectangular’ means any angle between 89° and 91°.” The attacked embodiment has an angle of 80°. No literal infringement, based on a proper claim construction. But might the claim as such be considered to cover the rectangular-ish 80° as an equivalent? The third question of Improver or Schneidmesser would preclude this, to maintain a reasonable degree of legal certainty for third parties. The present decision does not make clear how the Swiss Supreme Court would decide on this.

  2. It’s a European Patent, and it’s codified what is to be done, not only under DoE:

    Article 69 The extent of the protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims.

    Seems to have been forgotten, huh?

    And look at the Protocol:

    Article 69 should not be interpreted as meaning 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. Nor should it be taken to mean 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 patent proprietor has contemplated. On the contrary, it is to be interpreted as defining a position between these extremes which combines a fair protection for the patent proprietor with a reasonable degree of legal certainty for third parties.

    There it is, the legal certainty for third parties! It’s a must!

    1. An interesting aspect in Simon’s review of the decision is the following:

      Interestingly, the Federal Supreme Court found that the preliminary technical opinion of the Judge Rapporteur was correct and based its opinion largely on this document without knowing whether the Judge Rapporteur actually held to his preliminary opinion or had changed his mind during the deliberation in the first instance ruling.

      Let’s think this further: Indeed, the interim assessment of the reporting judge is established at an early stage of the proceedings. Nobody will ever know whether the reporting judge has changed his mind in the further course of the proceedings. And I trust that judges are receptive to good arguments, so this shouldn’t be too unlikely. But for the public it seems as if it was a majority decision of the court. So, why not publishing a kind of “consenting opinion” of the reporting judge in such cases, stating that he/she abstains from his interim assessement?

  3. Meanwhile, the Federal Patent Court in (bifurcated) Germany handed down a decision in a corresponding nullity action, 7 Ni 17/15(EP); see here. Infringement is not dealt with in this decision. Nevertheless, there is an interesting section I.4.f relating to the skilled person’s understanding of claim 1:

    “Schließlich weist das Rückschlagventil eine weitere, von dem Streifen (6) getrennte Komponente auf […]. Dies schließt nicht aus, dass der Streifen (6) und die weitere Komponente mittelbar verbunden sind, etwa durch die Verbindung des oberen Streifenendes mit dem Einlassabschnitt […], der seinerseits (durch Spritzguss oder Verklebung, siehe Streitpatentschrift, Absatz [0020]) mit der weiteren Komponente verbunden sein kann. Entscheidend ist vielmehr, dass der Streifen (6) selbst über seine gesamte Fläche von der weiteren Komponente getrennt, d. h. nicht unmittelbar mit ihr verbunden ist.”

    In a nutshell, the German court holds that ‘separate’ only precludes direct (“unmittelbare”) connections between the surface of the strip and the further component, but not indirect (“mittelbare”) connections.

    I need to sleep this over. In any event, it would be interesting to see a German court decide on infringement.

Leave a Reply

Your email address will not be published.