Neurotech patents in Europe: Part 3 - Sufficiency of Disclosure and the Plausibility Problem

Patent laws generally set out a sufficiency requirement that patent applications must satisfy in order to be granted and remain valid post-grant. Patent protection is an exchange – the proprietor discloses their invention in enough detail that it could be performed by a skilled person, and in return they are afforded a monopoly right over the invention for a fixed term. If an applicant obfuscates their invention, intentionally or not, they have not upheld their end of the bargain and likely will not be granted a patent.

European case law combines the legal requirements for sufficiency of disclosure and inventive step into a requirement of plausibility: there must be no serious doubts or evidence that the claimed effect cannot be obtained. Devices are not typically subject to plausibility requirements, although it is not unheard of (T 0575/17). In any case, all medical device patents are subject to sufficiency requirements.

In most cases, it is possible to read a patent application in the field of engineering and use the general knowledge from that field to determine whether the invention would work as described. However, this is not always true in neurotech. Where possible, it is still important to illustrate that certain aspects of the invention are supported by theory, or known from the prior art, as long as the invention has at least one novel feature. Sufficiency objections are uncommon in engineering applications and present an additional challenge for medical devices.

It is important to provide as much specific information in a patent application as possible, even for versatile devices which may be used on different tissue types. Providing at least one worked example allows the skilled person to confirm that the invention works as described without the need for significant trial and error. It may not always be possible to provide a scientific explanation of how an invention works. However, the invention is still sufficiently disclosed if the application contains experimental proof of the technical effect. The skilled person may compare their own results with the experimental data in the application.

Sufficiency of disclosure must be established at the date of filing. Nonetheless, if an invention is plausible, post-published data may be used to confirm the teachings of the application as filed, and in vitro data will often be sufficient. The EPO consider clinical trials to be confidential. If a claimed neuromodulator technology is mature enough to have reached clinical trials, this will not be considered a novelty-destroying disclosure. However, this is not true of all jurisdictions. Where possible, it may be more prudent to delay filing until the experimental results have been gathered and include them in the application.

Ensuring that an invention is novel and inventive is crucial for a successful patent application. However, it is important that these requirements do not overshadow the need for sufficient disclosure. Although it is not always feasible to wait until an invention is fully development to file a patent application, applicants should consider their timing carefully.

Neurotechnology is multidisciplinary, requiring collaboration between neuroscientists, engineers, and surgeons to name a few. It follows that neurotech patents would face challenges associated with both engineering and life sciences. In this brief series I have aimed to highlight aspects of European patent law which may not be familiar to engineers. If applicants are aware of these potential pitfalls, even during the research and development phase, it may help to clear the course towards granted patents.