EPO considers what data can support patent applications

Nicole Jadeja, Jules Fabre and Sarah Taylor of Pinsent Masons, the law firm behind Out-Law, were commenting after the European Patent Office’s (EPO’s) Enlarged Board of Appeal (EBA) was asked to determine what evidence must be included in the patent as filed and to what extent evidence published after a patent application has been filed can support claims made about the inventiveness of the process or product covered by the application. The EBA is the final arbiter on interpreting the European Patent Convention.

“The answer to this question is key for applicants to decide when to file their application: whilst they may be tempted to file early to secure protection and avoid prior art, they must also ensure that there is sufficient data available at the time of filing to be included in the specification” said Fabre.

To demonstrate that their inventions are patentable, applicants must, among other things, show that an inventive step has been taken that advances the known art and is not obvious to a person skilled in that art. At the EPO this is assessed by reference to the so-called problem-solution test.

Under that test, an applicant may rely on a particular technical effect attained by the invention to establish inventive step. Such effect must be supported by data and a question that arises then is whether the supporting data must be in the application or whether additional, post-published, data can be filed during examination, post-grant opposition or even litigation.

The EPO has developed the concept of ‘plausibility’ to answer that question and avoid purely speculative patents being granted. It said that when the applicant relies on a particular technical effect to establish inventive step, that effect must be plausible at the date the patent was filed.  Different lines of EPO case law in respect of plausibility and admissibility of post-published evidence have then arisen. According to a first line of case law, post-published evidence is admissible if the technical effect is made plausible based on date in the patent as filed. However, the EPO has also adopted a more flexible approach in other lines of case law.

To ensure uniform application of the law, the EBA has been asked to determine whether data, or other evidence, should be automatically disregarded if it has been published after a patent application has been filed and is the only evidence being relied upon and, if so, whether it can nevertheless be admissible applying a certain plausibility standard on data contained in the application.

Jules Fabre said the concept of plausibility has also been developed by case law in national courts and has become particularly relevant in the context of pharmaceutical patents.

“French courts, in particular, have developed significant case law on the evidence required for pharmaceutical patents, notably second medical use patents, to satisfy either the inventive step or the sufficiency requirement and reject patents which, due to the lack of data in the specification to support the alleged technical effect, are deemed speculative,” said Fabre.

For instance, in a 2019 judgement handed down in a case involving MSD against generic manufacturer Ethypharm on the anti-emetic drug aprepitant the Paris Court of Appeal specifically applied the concept of plausibility in the context of assessing inventive step. It said that to satisfy the criteria of inventive step under patent law it is not required to demonstrate the alleged technical effect in the patent specification with experimental data, provided the effect is specified in the patent and is plausible. The court reached that view following a 2017 landmark decision from the French Supreme Court in the case of MSD v Teva concerning finasteride, in which the Supreme Court said, in the context of sufficiency of description, that data in the patent must “directly and unambiguously reflect the claimed therapeutic application”.

In the UK, the Supreme Court, in a case involving pharmaceuticals manufacturer Warner-Lambert in 2018, considered the concept of plausibility in relation to whether the technical effect claimed by a patent had been disclosed sufficiently clearly and completely – ‘sufficiency’ of disclosure is a requirement of patentability set out in patent law.

Sarah Taylor of Pinsent Masons, the law firm behind Out-Law, said the referral of the questions around the admissibility of post-published data by the EPO’s Board of Appeal to the EBA was rare and significant.

Taylor said: “Plausibility is a hot topic both in a number of European courts, such as France and the UK and before the EPO. It is interesting that the EBA reviewed the UK Supreme Court’s decision in the Warner-Lambert case when considering this referral. There are recent examples of the UK courts  considering EPO and EU case law in relation to the issue, which shows the potential influence of decisions in other European jurisdictions.”

“However, the EBA did not refer a question on whether plausibility should be considered in respect of inventive step or sufficiency. There may therefore remain an area of divergence between EPO and approaches adopted in some European countries. It is likely to be a couple of years before the EBA decides the matter, and therefore entirely possible that there will be some national decisions on plausibility in the meantime, which further refine this area of patent law,” she said.

“We hope that the fact that this topic is being further considered by the EPO and national courts will provide further clarity for pharmaceutical companies on the question of how much data is needed to support any patent application. This is important because it feeds into the key question of when to file for a patent, a particularly important consideration for start-ups and SMEs in the life sciences sector often needing to demonstrate patent filings to support funding applications,” Taylor said.