A Swiss approach to the EPO’s gold standard

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Case No. O2016_016 | Decision of 6 June 2019

The patent at stake is MundiPharma‘s EP 2 425 825 B9; see EPO Register and Swissreg. EP’825 pertains to a combination of oxycodone hydrochloride (in an amount of 10 to 150g) and naloxone hydrochloride (in an amount of 1 to 50g), in a weight ratio of 2:1.

This combination is an analgesic drug that is available as modified-release tablets under the trade name Targin® by MundiPharma.

Develco’s logo

Develco sought annulment of EP(CH)’825 for various reasons, i.e. undue extension of subject-matter, non-enablement and invalidity of the priority claim. Please see this Blog here for a brief summary of the main hearing in this matter, and some relevant prior art Develco has asserted against patentability of the claimed subject-matter.

MundiPharma’s logo

Defendant / patentee MundiPharma countersued for infringement. MundiPharma not only countersued the plaintiff, but rather also attempted to involve the German branch of Develco as well as Konapharma. This attempt failed.

It was evident from the pleadings at the main hearing that the expert opinion of the judge-rapporteur had held that the patent was invalid for undue extension of subject-matter. Thus, it does not come as a big surprise in the decision that EP(CH)’825 is held invalid for undue extension of subject-matter. Consequently, the decision does not address the other grounds of invalidity asserted by Develco; and the counterclaim for infringement is moot, too.

In my perception, the detailed assessment of undue extension of subject-matter is nothing out of the ordinary. It’s all about the EPO’s ‘gold standard’ (G 2/10 in ¶4.3, with reference to G 3/89 and G 11/91), i.e.

[…] any amendment […] can […] only be made within the limits of what a skilled person would derive directly and unambiguously, using common general knowledge, and seen objectively and relative to the date of filing, from the whole of [the application as filed].

What is interesting, though, is how the decision addresses the so-called essentiallity-test (‘Wesentlichkeits-Test’), in particular how this test fits with the ‘gold standard’. In brief, in T 331/87 the Board held that the replacement or removal of a feature from a claim may (referred to in the Case Law of the Boards of Appeal as a ‘might’) not be in breach of Art. 123(2) EPC if the skilled person would directly and unambiguously recognise that

  1. the feature was not explained as essential in the disclosure;
  2. it was not, as such, indispensable for the function of the invention in the light of the technical problem it served to solve; and
  3. the replacement or removal required no real modification of other features to compensate for the change.

It is important to note that even this Board apparently (in view of the conditional language used; see mark-up above) did not consider compliance with the above three criteria as a sufficient condition for compliance with Art.123(2) EPC in any given case. Accordingly, the present decision holds that the only thing that really matters is the ‘gold standard’ discussed above, which cannot be deviated from. With reference to the Swiss Supreme Court decision 4A_109/2011, 4A_111/2011 (¶4.3.1), however, the decision further holds that in a case where not even the criteria of the essentiallity test are fulfilled, it must be assumed that an undue extension of subject-matter occured.

What suprises me, though, is that the decision holds (¶31):

Otherwise this would again amount to a materiality test, which was expressly rejected in G 2/98.

Frankly, I don’t see that in G 2/98, at least not expressly (‘ausdrücklich’). One may well conclude from the gist of G 2/98, in particular ¶8.3, that it does not endorse a distinction of technical features which are related to the function and effect of the invention and technical features which are not. But there is no discussion of the essentiallity test at all in G 2/98. Else, if there was, the essentiallity test would surely not be referred to anymore in the most recent edition of the Case Law of the Boards of Appeal and the Guidelines.

But still, my personal take-away message from this decision is that the essentiallity test is of no avail in proceedings at the FPC (until someone comes along and proves me wrong).

The decision is not yet final / may still be appealed to the Supreme Court.

Reported by Martin WILMING


Case No. O2016_016 | Decision of 6 June 2019

Develco Pharma Schweiz AG
MundiPharma Medical Company

Panel of Judges:

  • Dr. Daniel M. ALDER
  • Dr. Tobias BREMI
  • Dr. Hannes SPILLMANN


  • Dr. Tobias BREMI

Court Clerk:


Representative(s) of Develco:

  • Andrea MONDINI (TIMES)
  • Dr. Cornelia HOFFMANN (SBMP), assisting in patent matters

Representative(s) of Mundipharma:

  • Dr. Simon HOLZER (MLL)
  • Dr. Dirk BÜHLER (Maiwald), assisting in patent matters
  • Dr. Andreas LEDL (Maiwald), assisting in patent matters


Don’t be misled by the patent no. on the bottom of the title page. EP 2 245 825 is a typo; this should read EP 2 425 825.
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