Can I disclose my invention after an initial patent application has been filed?

Can I disclose my invention after an initial patent application has been filed?

This is a thorny issue. Patent applicants are often under pressure to make non-confidential disclosures of their inventions once a first patent application has been filed. This might be in order to publicise or sell their inventions, or because potential licensees and commercialisation partners are not prepared to sign confidentiality agreements, or because there is a desire to publish an academic paper. However, as the example below illustrates, making a non-confidential disclosure of an invention, even after filing an initial patent application, can seriously or fatally compromise the scope of protection that can validly be obtained.

Many high-technology inventions which are the subject of pending patent applications are commercialised using confidentiality agreements, maintaining secrecy for as long as possible. Indeed, confidential information can be protected by the law of confidence as well as by contract law, where there is a contract. Once information is made public, it cannot in principle be protected with a confidentiality agreement and so this commercialisation option is weakened or lost.

Where our clients are under pressure to disclose their inventions, we help them to understand in detail the risks involved in making non-confidential disclosures and discuss what types of disclosure minimise risks. We review whether their patent application(s) already on file are likely to be adequate, or whether they may need to file further patent applications before disclosures are made. We aim to enable our clients to make an informed decision as to what to disclose, to whom, how and when.

The following example serves to illustrate the problem posed by non-confidential disclosures made after the filing of a first patent application.


Imagine that an inventor is the first person to devise the idea of a bicycle which has a bell. He files a patent application for this idea. A week later, the inventor issues a press release describing the bicycle with a bell and demonstrates it in public, putting the idea firmly into the public domain. The patent application already on file is not in itself affected by these disclosures.

A week later, the inventor realises that the idea could have broader application and that a bell could usefully be fitted to a train, a car, a truck or any other type of vehicle. The inventor wishes to obtain patent protection for this broader idea and files a revised patent application including the broader concept of a vehicle with a bell.

If he had not disclosed his invention, the revised patent application might have led to grant of a valid patent for the broader idea of a vehicle with a bell. Unfortunately, as a result of the disclosures, the idea of a vehicle with a bell is not now new. This is because one example of a vehicle with a bell (namely the bicycle with a bell) is already known to the public due to the press release and demonstration. Thus, a broad claim to a vehicle with a bell is now invalid due to a lack of novelty, at least in Europe. (Claiming priority from the first application does not help as the earlier application only disclosed a bicycle with a bell and so this priority claim would not be valid under current European Patent Office practice).

Specific claims to, for example, a train with a bell, or a car with a bell, may be new but it would be very difficult to argue that any of these concepts are inventive over public disclosure of a bicycle with a bell.

In this example, disclosure has prevented the inventor from broadening the scope of his protection, at least by way of a UK or European Patent. Disclosures after the filing of a first patent application can also cause serious or fatal problems in other circumstances, for example, where:

  1. the patent applicant subsequently wants to narrow the scope of protection sought to include specific features which were not fully disclosed in the initial patent application;
  2. the patent applicant subsequently wants to otherwise amend the scope of protection sought in a way which was not disclosed in the initial patent application, perhaps as a result of becoming aware of previously unknown prior art;
  3. it is discovered that the initial patent application is invalid or cannot be used as the basis for a valid priority claim, perhaps because the example given in the initial patent application turns out not to enable the skilled reader to carry out the invention.


In order to avoid compromising the scope of patent protection that can be obtained, the best legal advice is to not make non-confidential disclosures of an invention even once an initial patent application has been filed. If commercial realities mean that it is desirable to make non-confidential disclosures, then it is important to take legal advice beforehand in order to understand and, if possible, minimise the risks involved.

Further information about disclosing inventions is summarised in this PDF.

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