Application of G 2/21 in recent Board of Appeal decisions (T 1822/23 and T 432/24)
According to G 2/21, 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.
T 1822/23 and T 432/24 are among the most recent decisions where the Boards of Appeal have had to consider whether those requirements were satisfied.
Claim 1 at issue was directed to a method for reducing low-speed pre-ignition (LSPI) events in a boosted combustion engine by using a lubricating composition comprising, amongst others, an overbased calciumsulphonate detergent at a particular concentration. LSPI performance was the focus of the application as filed, while calcium sulphonate itself was not recited in original claim 1.
The closest prior art disclosed similar compositions comprising an overbased calciumsalicylate as the detergent (disclosed as a preferred detergent in the application as filed).
The patentee filed data demonstrating the improvement in reducing LSPI events of the compositions according to claim 1 over compositions comprising calcium salicylate.
The opponent argued that the purported effect could not be relied upon, as the application as filed did not disclose that the improvement in reducing LSPI events was linked to the nature of the detergent.
However, the Board said that the application as filed attributed improved LSPI performance to the composition as a whole, and not to any single component of it; thus, the purported effect could be relied upon. The Board relied on paragraph [0001], which simply read:
“The disclosure relates to lubricant compositions containing one or more oil soluble additives and the use of such lubricating oil compositions to improve low speed pre-ignition”.
Thus, the patentee was allowed to rely on the purported effect. The Board’s reasoning mirrors that in T 1950/23 (see (1) below; same technical field and the same Board), according to which:
“it would be an overly strict interpretation of G 2/21 to require that the application as filed demonstrate that the improvement of a technical effect disclosed in the application as filed and relied on by the patent proprietor is specifically attributed to the distinguishing feature”
There is no mention of this in the decision, but calcium salicylate was listed in the original dependent claims as a possible detergent alongside calcium sulphonate. There is a decision applying G 2/21 where the disclosure of an embodiment taken as the closest prior art alongside the claimed embodiment (with equal level of preference) in the application as filed proved fatal for the patentee (T 314/20, see (2) below). That said, digging deeper into the description of the present case, it could be seen that preference for calcium sulphonate was in fact expressly indicated; in addition, all examples related to calcium sulphonate and the application contained embodiments disclaiming calcium salicylate.
This is one of a small number of decisions where the “encompassed by “ and “embodied by” requirements are treated as separate aspects.
Claim 1 in suit was generally directed to a tablet composition comprising cabozantinib malate and various excipients in specific concentrations. Claim 1 was based on one of the compositions disclosed in the claims as filed in combination with certain preferred features taken from the description.
The closest prior art also disclosed a tablet composition of the same compound, but with certain different excipients and different concentrations of the active ingredient and of the excipients.
The patentee relied on data showing reduced formation of 6,7-dimethoxy-quinoline-4-ol, a degradation product of cabozantinib malate. There was no mention of 6,7-dimethoxy-quinoline-4-ol in the application as filed. The purported effect was formulated as the improvement in long-term storage stability of the composition.
The opponents argued that the alleged technical effect (long‑term storage stability) was not encompassed by the technical teaching of the application as filed. The key arguments were that:
(a) storage stability was mentioned in the background section of the original application, in the context of the problems addressed by the disclosure of the application, but the relevant wording suggested that this property would not necessarily be common to all of the disclosed compositions (and thus would not necessarily apply to the specific composition currently claimed):
Generally, drug developers endeavor to discover a pharmaceutical composition that possesses desirable properties, such as satisfactory water-solubility (including rate of dissolution), storagestability, hygroscopicity, and reproducibility […] . Accordingly, discovery of pharmaceutical compositions that possess some or all of these desired properties is vital to drug development.
(b) the purported improvement was in contradiction to the technical teaching of the application as filed; the application mentioned some of the excipients of the closest prior art as suitable excipients for use in the claimed compositions (there is no mention of this in the present decision, but this attack is somewhat similar to the reasoning of the Board in T 314/20 mentioned above)
On point (a), the Board generally considered that the above disclosure was sufficient for the purported effect to be encompassed by the technical teaching of the original application. According to the Board, some degree of generalisation had to be applied to the disclosure of the application, and the fact that storage stability was mentioned amongst other possible properties did not automatically mean that this property was not encompassed by the technical teaching of the original application. Finally, G 2/21 did not necessarily require a purported effect to be individualised in the application.
The Board also appears to have sided with the patentee on the position that “storage stability is generally a desired property when preparing pharmaceutical compositions”. T 1847/23 (see (3) below) offered a slightly different take on the matter (though this was in the context of low temperature storage stability).
On point (b), the Board did not see such a contradiction; they noted that the specific excipients of claim 1 were clearly disclosed as preferred in the original application (the excipients were apparently preferred ones from each respective class of excipients disclosed, and all examples contained the specific combo of excipients as in claim 1).
In their arguments against the “embodied by the same originally disclosed invention” criterion, the opponents said that there was no indication in the application as filed that the purported effect was observed due to the specific combination of excipients of claim 1.
One of the opponents also appears to have cited T 116/18, which expresses the “embodied by” criterion as the question of ‘would the skilled person, taking into account the common general knowledge and the application as originally filed, have legitimate reasons to doubt that the purported technical effect could be achieved with the claimed subject matter?’
The present Board said that irrespective of the interpretation of T 116/18, the key issue of G 2/21 was to identify the “technical teaching” of the application as filed. The Board then observed that the original disclosure of the claimed composition was “very specific”, and the compositions of claim 1 at issue included a preferred combination of excipients.
For the Board, this meant that the effect of improved storage stability did not change the nature of the claimed invention, as defined in G 2/21, so that it was embodied by the same originally disclosed invention.
References
(2) https://www.epo.org/en/boards-of-appeal/decisions/t200314eu1
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