Introduction
As discussed in an earlier article in this series, there is no ‘ideal’ time for filing a patent application. A trade-off must be made between filing the ‘perfect’ patent application with data that exhaustively cover all possible embodiments falling within the scope of an ideal broad claim, and the need to secure legal certainty by obtaining a filing date. So, what happens if you need to file your application, but you don’t have time to obtain all the required data before the filing date? Can anything be done down the line to improve the situation, if necessary? Our previous article discussed whether post-filed data can be used to support sufficiency, particularly in relation to second medical use claims. In this article, we discuss whether post-filed data can be relied upon during patent proceedings before the European Patent Office (EPO) in support of inventive step.
Inventive Step at the EPO
First things first, why might you need to rely on post-filed data? By way of example, imagine that your European patent application is being examined by the EPO. The Examiner considers independent claim 1 to be novel over cited prior art document D1, but that it lacks an inventive step (i.e. the Examiner considers the feature of the claim that distinguishes it from D1 to be obvious). Whilst your application contains some supporting data, it would be useful to submit further post-filed data to help demonstrate that claim 1 is not obvious over the disclosure of D1. A patent proprietor may be faced with a similar scenario during opposition proceedings in relation to their granted European patent.
In Europe, the inventive step of a patent claim is assessed using the problem and solution approach. This formulaic test involves the following steps:
- Determining the closest prior art (CPA) to the claimed invention;
- Assessing the technical effects achieved by the claimed invention when compared with the CPA;
- Defining the technical problem to be solved, the object of the invention being to achieve these effects; and
- Considering whether or not the claimed solution, starting from the CPA and the objective technical problem, would have been obvious to the skilled person.
As such, the EPO’s assessment of inventive step focusses on demonstration of the technical effect achieved by the distinguishing feature of the claim over the CPA. However, given the CPA may end up being a document you were unaware of during drafting (because it has been found in a search by the EPO or an opponent), it is quite possible that the data contained in your application will not contain direct comparisons with the CPA.
G2/21
Last year, the Enlarged Board of Appeal of the EPO issued decision G2/21, which provides a test for assessing whether post-filed data can be used to aid the assessment of inventive step. The main conclusions from the decision were:
- Evidence submitted by a patent applicant/proprietor to prove a technical effect relied upon for inventive step may not be disregarded solely on the ground that it is post-filed evidence (i.e. that it had not been public before the filing date of the patent in suit and was filed after that date); and
- A patent applicant/proprietor can 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 the effect as being encompassed by the technical teaching and embodied by the same originally disclosed invention.
G2/21 therefore confirmed it is possible to submit post-filed data during EPO proceedings. However, in order for that post-filed data to be considered in the assessment of inventive step, the Enlarged Board considered that it is first necessary to assess what the skilled person would understand at the filing date of the application as originally filed as the technical teaching of the claimed invention, taking into account the common general knowledge. If the technical effect intended to be relied upon for inventive step is encompassed by this technical teaching and embodied by the same originally disclosed invention, then that technical effect can indeed be relied upon and post-filed data can then be used to support that technical effect.
If this still seems like a relatively abstract test, decisions issued since G2/21 provide some further guidance on how the test might be interpreted in practice. Without attempting to provide a comprehensive analysis of the case law, we have picked out a handful of illustrative cases, which we feel offer some useful lessons.
Our first case illustrates a relatively straight-forward situation, showing where the test of G2/21 can readily be satisfied. In T1329/21, the key feature of the invention was the use of a particular type of cellulose in a cosmetic product. The application as filed discussed that this type of cellulose offered improved sensory properties on the skin, as compared with the type of cellulose normally used in the art. This effect was evidenced in the application as filed using comparative examples.
During opposition proceedings, the CPA disclosed yet another type of cellulose, not addressed in the comparative examples. In order to demonstrate a technical effect of the invention over the CPA, the patentee sought to submit new comparative data, showing the claimed cellulose again offered improved sensory properties over the cellulose of the CPA. In view of the test in G2/21, the Board found the new data to be clearly admissible:
The Board notes that achieving improved sensory properties was already disclosed as an objective in the original application. In addition, various sensory properties… of claimed formulations were evaluated… in the original examples… The effect reported in the subsequently published comparative test is thus clearly covered by the technical teaching disclosed in the original application.
In this case, the advantages of the invention were clearly described in the original application, and were evidenced using comparisons against the known prior art. Under the standard of G2/21, it was then easy to rely on the same effect when presented with a new - though not dissimilar - piece of prior art.
In T728/21, claim 1 of the main request under appeal was directed to a tablet formulation comprising a solid dispersion of amorphous Compound 1, for use in treating or lessening the severity of cystic fibrosis in a patient. Versus claim 1 as granted, significant limiting amendments had been made, including in relation to the components required to be present in the composition and the amounts thereof.
The CPA was determined to be a document describing various solid forms of Compound 1. This document disclosed that Compound 1 may be provided in the form of tablets and, whilst it did mention the use of conventional excipients for this purpose, the document did not disclose any specific tablet formulation. The difference between claim 1 and the CPA was therefore the definition of the particular composition of the claimed tablet.
The application as filed included tablet dissolution data in its examples section. However, during appeal proceedings (and the earlier opposition proceedings), the patentee submitted new data to support that a tablet having the specific composition of claim 1 exhibited optimised dissolution. The Board commented that the application as filed:
explicitly addressed the dissolution of tablets comprising a solid dispersion as an aspect of the disclosed invention and specifically described the claimed tablet composition as an embodiment of the disclosed invention.
In light of this, the effect of optimization of the dissolution associated with the specific tablet composition of claim 1, as demonstrated by the post-filed data, could be taken into account for the assessment of inventive step. The objective technical problem was therefore formulated as the provision of a tablet formulation comprising a solid dispersion of amorphous Compound 1 which exhibits optimized dissolution, and the claim was ultimately found to be inventive.
In addition to the advantages of the invention being clearly described in the original application, fall backs had also been included to provide basis to limit the claims to a more specific composition. Together, these two aspects paved the way for the patentee to rely on post-filed data that demonstrated that the stated advantages were achieved by the specifically claimed composition.
As we have seen, G2/21 does offer an insurance policy for dealing with prior art – and other new facts and objections – not known at filing. However, this should not be considered a free pass, and EPO case law comprises examples where post-filed data was rejected under the regime of G2/21.
In T852/20, a particular compound in crystalline Form 1 was claimed. The CPA disclosed that same compound in a different crystalline Form 2.
In formulating an objective technical problem for the purpose of inventive step, the patentee therefore sought to provide evidence that the claimed Form 1 offered an improved technical effect over Form 2. Post-filed data was submitted, showing that Form 1 had the superior bioavailability.
However, not only did the application not directly disclose – nor provide any pointers in the form of data or description – that Form 1 was more bioavailable than Form 2, the application instead taught that crystalline forms in general have lower bioavailability than alternative amorphous forms. The Appeal Board thus found that an improvement from Form 1 over Form 2 was not derivable from the application as filed, in contradiction of the test in G2/21. This was despite the application identifying improved bioavailability as a goal of the invention.
The Board summarised:
…if anything, the skilled person would derive from the application as filed that amorphous forms are more soluble and bioavailable than crystalline forms. By no means could the skilled person derive from the application as filed that one particular crystalline form, namely the claimed Form 1, has good solubility and bioavailability, let alone solubility and bioavailability that is better than that of another crystalline form (Form 2) ... Therefore, [the post-filed data] cannot be taken into account for formulating the objective technical problem, in accordance with G2/21.
Having discarded the post-filed data, the problem to be solved had to be formulated as the mere provision of an alternative form of the compound. Under this problem, Form 1 was considered an obvious alternative, obtainable from a routine and arbitrary selection of reaction conditions. Inventive step was refused.
The outcome of this case suggests that “name-dropping” a desired result is not sufficient for a technical effect to be derivable. Instead, the application as filed needs to tell the story of how this result is achieved by the claimed invention. By initially disparaging the performance of the crystalline forms, the application in this case perhaps also fell into the trap of “saying too much”, restricting the room for manoeuvre when new arguments needed to be developed.
We think this speaks to the importance in patent drafting of contingency planning. Should things not go as planned during examination or opposition, it is important to have considered what fall-back positions you might adopt, both for claim amendments and accompanying arguments. When drafting the application, it might therefore be important to ask: does the application include anything which compromises these fall backs? Does the application at least begin to tell the story of how these fall-backs meet the different aims of the invention? What data might be required to finish the story if needed, and have we laid the ground-work for its inclusion?
Finally, when an evidenced technical effect cannot be relied upon, this case demonstrates the difficulty in arguing for inventive step at the EPO when the objective problem is formulated as the “provision of an alternative for X”, rather than the more ambitious “provision of an improvement in Y”. In the latter case, even a simple difference might not be considered obvious, provided that the related improvement would not have been expected. Without a technical effect, it is much more difficult to argue that an alternative feature or ingredient would not have been contemplated by the skilled person.
Conclusion
In summary, there is nothing barring a patent applicant or proprietor from submitting post-filed data to the EPO. However, as outlined in the example cases above, whether the post-filed data can be used to assess the inventive step of a claim depends upon whether or not the requirements of G2/21 are met. With this in mind, we would encourage drafting your application in a way which tells the story of your invention, explaining how and why it offers an improvement over the known prior art, with a mind to potential fall back positions. This will improve the chances of any future data being deemed encompassed by the original teachings, and should smooth the path to inventive step.
