Europees Octrooibureau, 23-03-2023, nr. G 0002/21

The patent proprietor, the opponent, the President of the EPO and the majority of third parties either explicitly or implicitly considered the referral admissible.

BAYER AG and epi submitted that the referral should be regarded as inadmissible because the outcome of the appeal case was not dependent on the referred questions. According to BAYER AG, the answers should not impact the outcome either way when considering the principle of equal treatment of the parties. Post-published evidence may be taken into account based on the principle of free evaluation of evidence, or it may not. Hence, if the opponent was allowed to file verifiable facts to substantiate doubts, the patent proprietor must be allowed to likewise file verifiable facts to substantiate the effect made plausible in the application. Either way, in the case before the referring board this would mean that the subject-matter of the claims was to be considered inventive. For epi, document D21 needed to be taken into account by the referring board under the type I approach and pointed out that there was no divergence in the case law.

The patent proprietor derived from the case law of the boards of appeal in general and from the discussion in the context of the particular case leading to the referring decision that there were two different standards.

The first standard was for acknowledging a technical effect, i.e. whether the purported technical effect was achieved over the whole range of the claim. For this, the patent proprietor referred to decision T 939/92 (point 2.6 of the Reasons), which required that in order for a technical effect to be taken into account, it must be credible that substantially all claimed embodiments possessed the technical effect. If that requirement was fulfilled, the technical effect was to be taken into consideration for determination of an objective technical problem.

The second standard was for allowing a post-published document supporting a technical effect to be taken into account. For this the patent proprietor referred to decision T 1329/04 (point 11 of the Reasons) according to which such a document could only be taken into account when it was at least plausible that a solution had been found to the problem which was purportedly solved. Once this standard was met, the applicant or patent proprietor could rely on a post-published document to demonstrate that the technical effect had been achieved over the whole range of the claim.

The opponent submitted that referred question 1 addressed both substantive patent law and procedural law issues, i.e. the issue whether an alleged technical effect, for which no direct proof existed in the application as filed, could be relied upon, and the issue whether post-published evidence should be disregarded as an exception to the principle of free evaluation of evidence. These two aspects should be clearly distinguished from each other.

The President of the EPO considered that the referred questions required clarification as to their scope and advocated that the questions be re-ordered and that either the questions be re-phrased or that their scope be extended to cover the concept of plausibility also under the patentability requirement of sufficiency of disclosure under Article 83 EPC. Efpia, likewise, suggested that the questions be clarified but to a lesser extent than the President of the EPO.

Equally, epi, Medicines for Europe, Fresenius Kabi Deutschland GmbH and BASF SE suggested to re-formulate question 1. [involved party 6] advocated a complete reformulation of the referred questions to focus on whether an additional requirement for ‘technical support in the application as filed’ was to be applied.

The opponent, in its response to the Enlarged Board's communication pursuant to Articles 13 and 14(2) RPEBA, asked the Enlarged Board for guidance as to how far principles governing post-published evidence in the context of assessing inventive step could also be applied in the context of assessing sufficiency of disclosure.

Some third parties (FICPI, epi, Patentanwaltskammer) encouraged that referred questions 2 and 3 be answered irrespective of the answer given to question 1.

The opponent, the President of the EPO and a number of third parties ([involved party 2], FICPI, BAYER AG, epi, AIPPI, efpia, IP Federation, CIPA) each presented the position that ‘plausibility’ per se was not a patentability requirement but was linked to the question whether or not an invention could be acknowledged and whether an applicant or patent proprietor was actually in possession of an invention at the time of filing the patent application.

In another amicus curiae brief (BiA), instead of suggesting any specific answer to the referred questions, the Enlarged Board was requested to consider an approach which lay between the two extremes of excluding post-filed data completely and not taking ‘plausibility’ into account at all in deciding whether to admit such post-filed data. Also BASF SE refrained from proposing specific answers and submitted more on the substance that technical effects to be relied on for justification of patentability must be credibly disclosed in the original application documents to the skilled person's satisfaction, whereby the detail of factual substantiation required for a credible disclosure was to be determined on a case by case basis.

Arguments generally in favour of applying the principle of free evaluation of evidence in an unqualified manner also in respect of post-published evidence on which a technical effect exclusively rests were submitted by the President of the EPO and were supported by various third parties ([involved party 1], Beiersdorf AG, [involved party 4], FICPI, BAYER AG, epi, EPLIT, Patentanwaltskammer, CNCPI, efpia, CIPA).

According to the President of the EPO, post-published evidence to prove a technical effect for acknowledgement of inventive step could not be relied on to fully replace such an indication in the application as filed. However, this does not require an exception to the principle of free evaluation of evidence. For this reason, the President of the EPO proposed to answer question 1 in the negative but, irrespective of this, submitted arguments understood to be generally in favour of the approach referred to in question 2.

Epi, supported by CIPA, additionally argued that any inquiry as to the credibility of a technical effect at the filing date of the application was entirely separate and could logically only ensue after the free and full evaluation of the post-published evidence had established that the technical effect did occur. However, insofar as the technical effect proven for the first time by the post-published evidence had not been mentioned in the application as filed, the applicant or patent proprietor could only rely on the technical effect in the examination of inventive step if that effect was within the spirit of the invention disclosed in the application as filed.

More generally, CNCPI considered the introduction of an exception to the principle of free evaluation of evidence unjustified, because the question of the proof of the technical effect in the context of the assessment of the inventive step was a jurisprudential construction.

According to some other third parties (Beiersdorf AG, BAYER AG, epi, EPLIT, CIPA) an affirmative answer to question 1 was incompatible with the notion of Article 117(1) EPC which allowed for a number of means of giving or obtaining evidence which were by their very nature post-published, i.e. hearing of parties, requests for information, hearing witnesses, opinions by experts and inspection. In another amicus curiae brief (Patentanwaltskammer), Article 113(1) EPC was referred to as being contradicted by a firm ruling for considering post-published technical information. Rather, post-published evidence had to be freely evaluated for its probative value. Any effect made plausible in the original application documents could be challenged or defended by evidence created or made after the priority date of the patent application.

A further third party ([involved party 4]) argued that, like the assessment of the closest prior art, the technical effect had to be assessed at the time a decision was taken.

Arguments generally in favour of accepting an exception to the principle of free evaluation of evidence by disregarding post-published evidence on which a technical effect exclusively rests were originally submitted by the opponent and also supported by various third parties ([involved party 5], [involved party 6], Medicines for Europe, Fresenius Kabi Deutschland GmbH, IP Federation, and an anonymous third party observation).

The opponent, supported by Medicines for Europe and Fresenius Kabi Deutschland GmbH, originally considered it inequitable if a technical contribution to the art could be a mere allegation to justify a monopoly right stemming from a granted patent based exclusively on evidence submitted years after the filing date. Doing so would allow a very low threshold to be met by an applicant at the time of filing a patent application because it would allow for a technical effect to be a mere speculation that could not technically contribute to the art. Thus, disregarding post-published evidence as the only piece of evidence for an alleged technical effect, for which no proof existed in the application as originally filed and which was not plausible on the filing date of the patent application, did not infringe the principle of free evaluation of evidence.

However, in their response to the Enlarged Board's communication pursuant to Articles 13(2) and 14 RPEBA (point 12 thereof), the opponent agreed with the Enlarged Board's view that the principle of free evaluation of evidence does not appear to allow the disregarding of evidence per se insofar as it is submitted and relied upon by a party in support of an inference which is challenged and is decisive for the final decision.

Some third parties ([involved party 5], [involved party 6], Medicines for Europe) pursued a more advanced approach of excluding from consideration any post-published evidence filed to support for a claimed technical effect when assessing inventive step. The principle of legal certainty of third parties required that the evidence underpinning the claim was known at the filing date and should be unalterable during the claim's lifetime.

Arguments generally in favour of taking into consideration post-published evidence if, based on the information in the patent application in suit or the common general knowledge, the skilled person at the filing date of the patent application in suit would have considered the effect credible were submitted by the opponent and were supported by various third parties (Medicines for Europe, IP Federation). Some third parties, although suggesting that question 1 be answered in the negative, supported an affirmative answer to question 2, either as additional considerations (FICPI, epi) or in the event that question 1 was answered in the affirmative (BAYER AG, CIPA). Despite the fact that the President of the EPO did not directly propose to answer question 2 in the affirmative, his arguments are understood to be generally in favour of this approach.

According to the opponent and some third parties (Medicines for Europe, IP Federation) it was essentially a matter of substantive patent law that a patent could only be granted if there was a patentable invention as of the filing date of a patent application. Thus, an alleged technical effect was required to be more than a mere speculation, but must be derivable from the application as originally filed and as constituting a technical contribution to the prior art. To this end, post-published evidence in support of an alleged technical effect present as of the filing date could be taken into consideration.

The opponent, in the response to the Enlarged Board's communication pursuant to Articles 13 and 14(2) RPEBA suggested the following test:

The President of the EPO emphasised that there was no distinct, separate patentability requirement of ‘plausibility’ but that it was to be understood from the EPC that an invention to be patentable required that a technical effect was attainable. An alleged technical effect as an inherent feature of any invention complying with Articles 56 and 83 EPC had to be made on the basis of the content of the application as filed in combination with the common general knowledge. A lack of such disclosure could not be made up for at a later stage by submitting post-published evidence showing that the alleged technical effect was indeed achieved. Post-published evidence could be taken into account to corroborate a credible disclosure at the filing date or to refute any allegation from opponents that the claimed technical effect could not be achieved. The evidence submitted by a patent proprietor to prove an alleged technical effect, which was already credibly disclosed at the filing date, or submitted by the opponent to prove that this technical effect could not be achieved, had to be assessed in accordance with the principle of free evaluation of evidence.

FICPI argued that in special circumstances, when the attainment of a particular technical effect was treated in a claim and thus part of the subject-matter of the invention, it was appropriate to consider whether the claimed effect was rendered credible in the application as filed. However, a claimed technical effect could be rendered credible even without having been proven, e.g. by means of extrapolation, analogy or a theoretical rationale, and the principle of free evaluation of evidence should be preserved in order to allow later proof, if needed, of a claimed effect that was rendered credible in the application.

BAYER AG and CNCPI also argued that the applicability of any approach had to be done on a case-by-case basis and depended on different aspects, like the respective technical field, the prior art and the predictability of the claimed technical effect without these aspects per se contradicting one another.

The patent proprietor submitted that the approach underlying referred question 2 was at most applicable for the assessment of sufficiency of disclosure (Article 83 EPC) for which it had initially been introduced by decision T 609/02, in particular where the technical effect was stated in the claim (T 939/92, point 2.2.2 of the Reasons). It should, however, not be applied to the assessment of inventive step (Article 56 EPC) of a claimed subject-matter because it would be extremely disproportional in terms of the legal effect, the awareness of the patent applicant and the burden of proof.

The patent proprietor argued in favour of taking into consideration post-published evidence as a proof of an asserted technical effect if, based on the information in the patent application in suit or the common general knowledge, the skilled person at the filing date of the patent application in suit would have seen no reason to consider the effect non-credible, this in particular with regard to patents directed to medical use. In such cases the applicant would be aware of the importance of the technical effect from the beginning of the patent granting procedure and would have mentioned it already in the patent application. Thus, the threshold for sufficiency of disclosure should normally be addressed by the applicant. With regard to inventive step, however, it would be highly unpredictable which technical effect the patent applicant should rely upon as the discussion of the technical effect depended on the choice of the closest prior art that is usually introduced after the filing date. Hence, the applicant would often be forced to argue for a technical effect of a distinguishing feature not focussed on when filing the application.

One third party (IP Federation) suggested to answer all three referred questions in the affirmative. It should be permissible to take into account post-filed data if, based on the information in the patent application in suit and/or the common general knowledge, the skilled person at the filing date of the application would have seen no reason to consider the technical effect non-credible, including if they considered the technical effect to be credible, based on the information in the patent application and/or the common general knowledge.

Other third parties, although suggesting that question 1 be answered in the negative, supported an affirmative answer to question 3, either as additional considerations (FICPI) or in the event that question 1 was answered in the affirmative (BAYER AG, epi, CIPA) in order to preserve the ability of an applicant to adduce additional evidence to support the technical effect associated with the subject-matter of the invention that, although not explicitly disclosed in the application as filed, sustained the spirit and character of the disclosed invention and was not implausible. CIPA advocated that any requirement for information in respect of ‘plausibility’, or lack of ‘implausibility’, at the filing date should be minimal. For example, it should suffice if the technical effect ultimately relied upon was merely ‘not completely implausible’, especially bearing in mind that at the filing date the applicant may not know the closest prior art from which the claimed invention must be distinguished.

The opponent argued that the approach underlying referred question 3 lowered the threshold to patentability significantly and allowed for patents to be granted on the basis of a at the filing date merely speculative technical effect, as opposed to a genuine technical contribution. If it was allowed to define an invention after the filing date, then anything disclosed in the application as filed could be ‘transformed’ into an invention after that effective date. Such an approach was incompatible with the requirement of Article 52(1) EPC according to which a patent shall be granted for any invention, provided that the invention had already been made before the patent application was filed.

Fresenius Kabi Deutschland GmbH additionally argued that although the burden of proof for a claimed technical effect normally rested with the patent applicant or proprietor, and the hurdle for opponents and examiners implied by question 3 was close to unsurmountable, it placed them at a severe disadvantage, and was simply unfair.

The principle of free evaluation of evidence is also acknowledged in Switzerland. The Swiss Code of Civil Procedure (Zivilprozessordnung) stipulates in Article 157 that the court forms its conviction after free evaluation of the evidence (‘Das Gericht bildet sich seine Überzeugung nach freier Würdigung der Beweise.’) which was interpreted by the Swiss Federal Supreme Court as a ban on fixed rules of evidence (see decision 5A_250/2012 of 18 May 2012, point E. 7.4.1 with further references). In its decisions, the Swiss Federal Patent Court refers to said provision (see Article 27 Patent Court Act (Bundesgesetz über das Bundespatentgericht — Patentgerichtsgesetz).

For Germany, the principle of free evaluation of evidence is provided for both in the Patent Act (§ 93(1) Patentgesetz) and in the Code of Civil Procedure (§ 286 Zivilprozessordnung). According to the former, the judge shall decide according to its independent conviction gained as an overall result of the proceedings (‘Das Patentgericht entscheidet nach seiner freien, aus dem Gesamtergebnis des Verfahrens gewonnenen Überzeugung.’).

French proceedings are in principle also governed by the principle of a free evaluation by the judge of the evidence submitted by the parties (‘appréciation souveraine par le juge des éléments de preuve qui lui sont soumis’; see J. Passa, Traité de droit de la propriété intellectuelle, Tome 2, Brevets d'invention, protections voisines, 2013, point 151, pages 202 and 203; J. Schmidt-Szalewski, Fasc. 4260 of Jurisclasseur Brevets, paragraph 48 ‘appréciation de la preuve des antériorités’). Regarding novelty however, the date, the content and the accessibility to the public of a document allegedly disclosing the invention must be certain.

In the Netherlands, Article 152(2) of the Dutch Code of Civil Procedure (Wetboek van Burgerlijke Rechtsvordering) regulates a free evaluation of evidence, unless the law provides otherwise (‘De waardering van het bewijs is aan het oordeel van de rechter overgelaten, tenzij de wet anders bepaalt.’). This exception concerns rules about the conclusive evidential value of evidence. The court is obliged to accept as true certain forms of evidence; however such evidence is also subject to a rebuttal supported by evidence. Although the Dutch legal system does not provide methodological guidance for judges on the free assessment of evidence the definition by C.H. van Rhee appears to be an accepted common definition of the principle of the free assessment of evidence in Dutch civil procedural law, according to which the judge decides on proof according to his ‘intimate conviction’, but within the boundaries set by the parties in their statements of facts.

In the United Kingdom with its common law system, there is no general principle of free evaluation of evidence. Evidence in relation to inventive step (obviousness) is considered a ‘jury-type question’ to be decided on the facts of the particular case at hand (see Terrel on the Law of Patents by C. Birss et al, 19th edition, 2020, pages 390–400 at [12-177]-[12-212], with many examples and references). Two types of evidence were defined and distinguished by the Court of Appeal in Mölnlycke v Procter & Gamble [1994] R.P.C. 49 at [112]: primary evidence (expert evidence) and secondary evidence (all other evidence), whereby in relation to obviousness for which an objective test is applied the primary evidence seems to be most relevant, although secondary evidence may also be treated ‘decisive in a proper case’ (Accord v Medac [2016] EWHC 24 (Pat) at [116]; see also Schlumberger v EGMS [2010] EWCA Civ 819 at [84]-[85]; Hospira UK Ltd, v Cubist Pharmaceuticals Ltd [2016] EWHC 1285 (Pat); Positec Power Tools Europe Ltd v Husqvarna AB [2016] EWHC 1061 (Pat); Cantel Medical (UK) Ltd v Arc Medical Design Ltd [2018] EWHC 345 (Pat)).

Before entering into a discussion of the case law of the boards of appeal, the Enlarged Board takes note of the decision in T 578/06, point 13 of the Reasons, where the board of appeal stated that the EPC required no experimental proof for patentability and considered that the disclosure of experimental data or results in the application as filed and/or post-published evidence was not always required to establish that the claimed subject-matter solved the objective technical problem. The board of appeal, while referring to T 893/02 and T 1329/04, emphasised in point 15 of the Reasons that this case law considered the establishment of a plausible reliance on a purported technical effect ‘only relevant when examining inventive step if the case in hand allows the substantiation of doubts about the suitability of the claimed invention to solve the technical problem addressed and when it is thus far from straightforward that the claimed invention solves the formulated problem. This is all the more clear from decisions where an inventive step was in fact denied because the formulated problem was not considered to have been solved.’

In a number of decisions, the boards of appeal excluded from consideration post-published evidence because the content of the evidence was not available to the skilled person at the relevant date (T 1791/11: as the sole basis for establishing that the application solved the problem it purported to solve; T 125/12: to support an effect that was non-plausible from the application as filed; T 1285/13: the assessment of inventive step was to be made at the effective date of the patent on the basis of the information in the patent together with the common general knowledge then available to the skilled person, post-published evidence filed to support the argument that the claimed subject-matter solved the problem to be solved was taken into account if it was already credible from the disclosure in the patent that the problem is indeed solved; T 2348/13: post-published articles D42 and D43 did not illustrate common general knowledge; T 488/16: As the post-published documents were the first disclosure showing that the purported technical problem had actually been solved, these documents were therefore not taken into consideration in the assessment of inventive step; T 1099/19: The claimed technical effect was not made plausible at the effective date of the patent, and the post-published documents were not taken into account as they were the first disclosure going beyond speculation).

There are also decisions by which the competent board of appeal considered post-published evidence submitted in the context of assessing a claimed technical effect, albeit without a different outcome on the issue of inventive step (T 179/16, T 978/16, T 1499/16, T 229/17, T 334/18, T 1306/18).

In T 108/09 post-published evidence was taken into account because the board of appeal found that this evidence had not been the only source of information regarding the claimed technical effect so that the data contained therein could be used in the evaluation of whether or not the problem underlying the invention in suit was plausibly solved.

The Enlarged Board is aware of the case law cited by the referring board as examples for different approaches to the acceptance of a patent applicant's or patent proprietor's reliance on an asserted technical effect (see points VI.(6) to (8) above and points 13.4 to 13.6 of the Reasons for the referring decision). As the volume of decisions on the relevance of post-published evidence, such as experimental data, to prove an alleged technical effect for acknowledgement of inventive step in the context of Article 56 EPC is too big to discuss in detail, the Enlarged Board focusses on a selection of in particular more recent jurisprudence, which the development of the earlier case law appears to culminate in.

In T 31/18, point 2.5.2 of the Reasons, which was categorised by the referring board as type III case law (see point 13.6 of the Reasons for the referring decision, also referring to T 2371/13, point 6.1.2 of the Reasons), the board of appeal held that the technical effect relied upon for inventive step according to the problem-solution approach must either be explicitly mentioned in the application as filed or at least be derivable therefrom, but not necessarily originally supported by experimental evidence. It could not be expected from a patent applicant to include an extensive amount of experimental evidence corresponding to all technical features which could possibly be claimed in the application as filed and which could possibly constitute a future distinguishing feature over the closest prior art, since said closest prior art and its technical disclosure may not be known to the applicant at the filing date of the application.

Decision T 1329/04 is mentioned by the referring board as a key example for the conceptional notion underlying referred question 2 (type I, see point 13.4 of the Reasons for the referring decision). The board of appeal in T 1329/04 did not take into consideration post-published evidence and ultimately denied an inventive step of the claimed subject-matter because the application as originally filed lacked enough evidence to make it at least plausible that a solution had been found to the purportedly solved problem. The relevant reasoning is to be found in points 10 and 11 of the Reasons (emphasis added):

According to T 235/13, T 787/14, T 488/16, T 2200/17, T 377/18, T 391/18 and T 1442/18, post-published evidence can be taken into account in support of a technical effect that was considered by the competent board of appeal plausible already from the application as originally filed. The following passages from the aforementioned decisions appear decisive for the particular board of appeal for its findings:

There are also decisions in which post-published evidence was not taken into account because that evidence was regarded as the sole basis for establishing that the technical problem was indeed solved. Post-published evidence filed to support the argument that the claimed subject-matter solved the problem to be solved could only be taken into account if this was already credible from the disclosure in the patent:

Examples of decisions taking post-published evidence into consideration only if the skilled person at the filing date of the patent application in suit would have seen no reason to consider the effect implausible, as underlying referred question 3 (type II, see point 13.4 of the Reasons for the referring decision) are T 536/07, T 1642/07, T 1677/11, T 919/15, T 2097/15, T 184/16 and T 2015/20.

The Swiss courts have apparently not developed any specific criterium in this regard, as confirmed in the AIPPI 2019 — Study Question — Plausibility.

The Enlarged Board takes note of the more recent Swiss Federal Court decision (4A_149/2021) in deciding on an appeal against a decision of the Swiss Federal Patent Court, while referring to the case law of the boards of appeal that advantages in formulating the problem to be solved can only be taken into account if the person skilled in the art can derive the purported effect from the documents originally filed against the background of the closest prior art or if this effect is implied in the documents originally filed. In the absence of such an implication, courts may assume that the invention is merely an alternative and not an improvement over the prior art, and that any subsequent attempt by the patent proprietor to prove the invention's originality is irrelevant.

In the German patent law related literature an opinion (see Ackermann, GRUR 2021, 3) is held that German case law does not allow a reliance on post-dated evidence if the advantages shown therein make a significant contribution to the invention or even constitute its core. The objective problem the person skilled in the art is faced with cannot be influenced by a technical teaching that extends beyond the original disclosure.

In another opinion (T. Exner/A. Hüttermann, GRUR 2018, 97), the case law of the boards of appeal since T 1329/04 was considered; it was noted that the requirement that a claimed effect must be plausible was rather foreign to the classical German understanding.

The Enlarged Board understands from the decision ‘Erlotinib hydrochloride’ (3 Ni 20/15, point II.3.c.5) of the Reasons) of the German Patent Court, referring to a decision of the boards of appeal (T 390/88) and two decisions of the German Federal Court of Justice (X ZB 3/69 — Anthradipyrazol; X ZB 2/71 — Imidazoline) that post-published evidence for an alleged technical effect can be taken into consideration. The Court considered it sufficient that the subject-matter of the claimed invention actually achieved an improvement in the sense of a therapeutic advance or that a hitherto unmet public need was met on the relevant date. The alleged improvement did not need to be documented on the filing date, rather documents in support of said improvement could be submitted later.

The pertinent line of case law in France appears to be particularly addressed in the context of sufficiency of the disclosure as a patentability requirement and the field of chemistry, more specifically of medicines (e.g. Cour de cassation, 15-19726 — Merck c/ Teva; Tribunal de Grande Instance de Paris 07/16446 — Teva / Sepracor, and 16/01225 — Ethypharm / MSD; see also AIPPI 2019 Study — Plausibility in the group report for France). Post-published evidence is sometimes taken into account, albeit without any specific criteria being set out explicitly. Such documents are considered to be relevant in particular when relied upon to support the findings in the patent application, rather than to compensate for an intrinsic deficiency. The vast majority of French case law does not contain any express discussion of criteria linking the admissibility of post-published documents and the notion of ‘plausibility’.

Also the Dutch courts appear to not apply the notion of plausibility as a separate concept but rather discuss this, if necessary, as an element of assessing inventive step of the claimed subject-matter, or of sufficiency of disclosure. In the decision of the Court of Appeal The Hague in case Leo Pharma v Sandoz (200.195.459/01) it was held that the contribution to the state of the art must be assessed from the perspective of the average skilled person at the application date, and that any effects the average skilled person would have considered not plausible at the application date must be disregarded in the context of the assessment of inventive step. The Court stated that there was no general standard of plausibility and that the patent proprietor did not need to provide complete evidence of the alleged effect in the application. However, the statements regarding the effect should not be merely speculative. If the effect was evident for the person having ordinary skill in the art when reading the patent, taking into account their common general knowledge, it was not necessary to disclose and substantiate the technical effect in the application. However, if the effect was not evident for the person having ordinary skill in the art, the threshold for disclosing the effect was higher. A later decision in case Astrazeneca v Sandoz of the Court of Appeal The Hague (200.237.828/01) does not deviate from this approach, where the Court found that the patent in suit made the alleged effects plausible. However, in the more recent case Bristol-Myers Squibb v Sandoz the District Court The Hague (C/09/627925 / KG ZA 22-326 — Bristol-Myers Squibb Holdings Ireland v Sandoz) appears to refer to what the referring board considered as ‘type II plausibility’ of which it was not convinced with regard to the patent application.

The High Court decision in Sandoz Ltd and another v Bristol-Myers Squibb Holdings Ireland Unlimited Co and another [2022] EWHC 822 (Pat) provides a summary of the case law on what the referring board discusses under the conceptual terminology of plausibility both before the national courts (Warner-Lambert v Generics [2018] UKSC 56, Fibrogen v Akebia [2021] EWCA Civ 1279) and the boards of appeal (i.a. T 609/02). The approach taken in Warner-Lambert v Generics [2018] has essentially been confirmed in the Court of Appeal decisions Illumina Cambridge Ltd v Latvia MGI Tech SIA and others ([2021] EWCA Civ 1924) and FibroGen Inc. v Akebia Therapeutics Inc. and another company; Astellas Pharma Inc. v Akebia Therapeutics Inc. and other companies ([2021] EWCA Civ 1279).

Post-published evidence may be relied upon only to confirm the existence of a technical effect which is plausible in the light of the specification and the skilled person's common general knowledge, and not to establish the existence of a technical effect for the first time (see C. Floyd, GRUR 2021, 185; P. Johnson, GRUR 2019, 524; A. Slade, Intellectual Property Law Quarterly 2020, 180; A.J.K. Wells, Journal of intellectual property law & practice 2019, Vol 14 issue 10, 784; see also from a more critical perspective R. Jacob, Bio-Science Law Review 2020, 17(6), 223;, all with numerous further references). An example where post-published evidence (data) was considered is the decision of the Supreme Court in Warner-Lambert Company LLC v Generics (UK) Ltd t/a Mylan and another ([2018] UKSC 56), which, however, dealt with the issue of sufficiency of disclosure. In that decision Lord Hodge (point 184 of the decision) held that the plausibility test in the context of sufficiency of disclosure allowed the court to have regard to such later evidence to make good the prediction if there was some basis for the prediction in the patent. He agreed with Floyd LJ in the leading judgment in the Court of Appeal (Warner-Lambert Company LLC v. Generics (UK) Ltd, [2016] EWCA Civ 1006, point 133 and also point 39) and treated the outcome of these tests as fortifying the judge's conclusion that the patent had contained a plausible prediction. Lord Sumption (point 41 of the decision) and two other judges found that such later acquired evidence was admissible only to confirm results rendered plausible by the patent specification. This approach is also to be found in the Patents Court's decisions in Actavis Group PTC EHF & Anr v Eli Lilly & Co ([2015] EWHC 3294 (Pat), point 181 of the decision) and in Saint-Gobain Adfors SAS v 3M Innovative Properties Co ([2022] EWHC 1018 (Pat)). However, there are also examples of decisions where such post-published evidence (data) was not considered, e.g. by the Patent Court in Eli Lilly and Co and other companies v Genentech, Inc ([2019] EWHC 387 (Pat), point 578) and in Generics (UK) Ltd trading as Mylan and another v Yeda Research and Development Company ([2017] EWHC 2629 (Pat), points 197 and 200).