Crystallising the interpretation of G 2/21 (T 1989/19)

The Board of Appeal in T 1989/19 provides further guidance on the interpretation of the Enlarged Board of Appeal decision G2/21. The reasoning in T 1989/19 is aligned with the interpretation recently taken by the referring Board to G2/21 (IPKat). In short, to be relied on for inventive step, a purported technical effect must be encompassed by the technical teaching of the application as filed understood in its broadest sense. Additionally, explicit basis for the technical effect is not required. Instead, there just needs to be an absence of substantiated doubt that the claimed invention would have the purported technical effect in view of the application as filed and common general knowledge.

G2/21: Case catch-up

In G2/21, the Board of Appeal referred to the EBA the question of whether post-published evidence could be taken into account for inventive step. The EBA ordered that:

"A patent applicant or proprietor may rely upon a technical effect for inventive step if the skilled person, having the common general knowledge in mind, and based on the application as originally filed, would derive said effect as being encompassed by the technical teaching and embodied by the same originally disclosed invention" (Headnote II, G2/21) 

We have now had a number of Board of Appeal decisions interpreting G2/21. Most notably, the referring Board of Appeal in T 0116/18 concluded that G2/21 does not necessitate a positive statement or experimental evidence of a technical effect in order for the said effect to be relied on for inventive step. In order to support inventive step, a technical effect must merely be "conceptually comprised" in the broadest technical teaching of the application as filed ("encompassed") (IPKat). Additionally, according to the interpretation of G2/21 by T 0116/18, the evidence standard with respect a technical effect relied on for inventive step remains whether a skilled person would have substantiated doubts with respect to the invention or its purported technical effect, in view of the application as filed and common general knowledge. The Board of Appeal in T 0116/18 equated this test with that of whether the technical effect is "embodied" by the technical teaching of the application as filed. 

Sufficiency of a product claim: Indication of at least one-way 

The first question on appeal in T 1989/19 was that of sufficiency. The case related to the opposition of EP 1785422. The granted patent claimed crystalline tiotopium bromide, defined inter alia by particle size and water content.The granted claim defined the crystalline product according to a number of parameter ranges. The application as filed provided an example product falling within these parameter ranges. The Opponent argued that the claimed product was not sufficiently disclosed over the whole scope of the claim. The Opponent further argued that a skilled person would understand from the application as filed that a particular manufacturing step was essential for producing the product. However, this manufacturing step was not specified in the claim. 

Crystals

The Board of Appeal rejected the Opponent's insufficiency argument. The Board of Appeal noted that the claim was a product claim and that the manufacturing step was not a feature of the claim. According to the case law, a product claim is sufficiently disclosed if the application as filed provides at least one way of performing the claimed invention (Case Law of the Boards of Appeal, II-C-5.2) [As previously discussed on IPKat, the UK courts are currently out of step with the EPO on this point)]. The application as filed in T 1989/19 provided an example of the claimed product, and the necessary manufacturing process. The Board of Appeal concluded that the Opponent's arguments therefore did not amount to substantiated doubt that a skilled person would be able to work the invention (r. 1.2.8). The claimed invention was thus found to be sufficiently disclosed. 

Inventive step: reliance on a technical effect not mentioned in the application as filed

Moving on to the question of inventive step, the feature distinguishing the claimed invention from the prior art was identified as the product's claimed water content. The Patentee submitted data purporting to show the technical effect of this feature as the improved storage stability of the product. The Opponent argued that the application as filed provided no indication of this purported technical effect, and that the post-filed data could therefore not be taken into account in view of G2/21. 

However, the Board of Appeal agreed with previous interpretations of G2/21 that it is not necessary for a technical effect relied on for inventive step to be expressly mentioned or established in the application as originally submitted (IPKat, IPKat). As interpreted by T 0116/18, G2/21 merely requires the purported technical effect to be "conceptually comprised by the broadest technical teaching of the application as filed" (T 0116/18, r.11.10). Accordingly, it may be "sufficient that the skilled person, having the common general knowledge in mind, and based on the application as filed, recognises that said effect is necessarily relevant to the claimed subject-matter." (T 0116/18, r.11.10).

In T 1989/19, the Board of Appeal noted that the application as filed focused on the use of compounds as inhalation powders and taught that a certain particle size range is required for administration by inhalation. From this general disclosure, the Board of Appeal found that it could be inferred that the particle size stability was an essential prerequisite for the administration of the claimed product. Furthermore, a skilled person would have been generally aware of the potential impact of particle size on stability and a crucial factor for the inhaled administration of a drug. As such:

"The skilled worker would therefore directly infer the storage stability of [the] product from [...] the application as filed. Nothing in the application as filed or in the common general knowledge can be inferred that calls into question the achievement of that storage stability by the subject matter of the claim, nor was such a doubt raised by the appellant. It can thus be inferred from the application as filed that this technical effect is encompassed by the technical doctrine of the application and is embodied by the invention originally disclosed." [r. 3.3.14, Machine translation from the German, emphasis added]

In other words, the Board of Appeal applied the tests of 1) whether the technical effect was encompassed by the original disclosure in it broadest technical sense, and 2) whether the skilled person would have any substantiated doubts, in view of common general knowledge and the application as filed, that the claimed invention would have the purported technical effect. Given the absence of any substantiated doubts with regards to the technical effect, the Board of Appeal found the claimed product inventive in view of the prior art. 

Final thoughts

In this Kat's view, G2/21 and its interpretation has not brought about a radical change in EPO practice. It has long been the case that an applicant may reformulate the objective technical problem to be solved in view of the closest prior art "provided that the skilled person would recognise these effects as implied by or related to the technical problem initially suggested" (Headnote, T 184/82, see also G‑VII, 11 ). Additionally, the "lack of substantiated doubts" test is an established standard for evidence in inventive step and sufficiency analysis (IPKat) and was reaffirmed G2/21 (IPKat).  

However, it is critical to remember that each case is determined by the facts. Crucially, more evidence of a technical effect will be required for certain types of invention for which there may be an underlying higher level of doubt (e.g. medical use inventions). The more complex and scientifically advanced the invention, the more evidence that will be required. However, this should not in any way be mistaken for a difference in the legal test, which remains the same regardless of technical field. This Kat muses that the confusion over whether or not the test for the standard of evidence before the EPO has changed over the years may find its origin in the ever increasing scientific complexity of the technology for which patent protection is sought. 

Further reading

• Plausibility demystified - a review of EPO case law before G 2/21 (Feb 2023)
• G 2/21: Is the technical effect embodied by the invention as originally disclosed? (March 2023)
• To encompass and embody: Applying the abstract principles of G 2/21 (May 2023)
• The relevance of G 2/21 to machine learning inventions (T 2803/18) (Aug 2023)
• Interpretation of G 2/21: Inventive step may be supported solely by post-published data (T 0116/18) (Sep 2023)
• Reliance on a silent technical effect: Application of G 2/21 to semiconductors (T 2465/19) (Oct 2023)
• G 2/21 does not permit armchair inventing (T 0258/21) (Oct 2023)
• Clarity on the interpretation of G2/21 from the referring Board (T 0116/18) (Nov 2023)

Image credit: DALLE-3