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How private is your product testing, and when should you file for a patent?

11th Sep 2020

Your engineers have been working on an exciting innovation. Their ideas have been developed in secret, and now they are ready for testing, which presents the issue of how to keep these new ideas secret. In the renewable energy sector, machines can be BIG. Consider GE’s Haliade X. This offshore wind turbine is 260 metres tall, and its rotor alone measures 220 metres. How do you test something like this in private?

It’s a difficult issue. An improved blade design, for example, is always going to have to be tested in the open at some point. And no matter how remote the testing spot, today’s technology means that people will be able to take photographs.

Patents are a key tool once an invention is out in the open, because they grant a monopoly to exploit the underlying ideas. But deciding when to file a patent application can be tricky. The initial filing has to include enough detail that someone with a reasonable amount of skill – the notional “skilled person” – could put the invention into practice. This is just what you have to give in return for your monopoly. However, the claimed invention also has to be new and non-obvious compared to what was known at the time the application was filed. And this, in Europe at least, includes “everything made available to the public by means of a written or oral description, by use, or in any other way”.

It is unlikely that you will come up against your own, or someone else’s, prior use in the stages leading up to grant of a patent, while you’re just dealing with patent office examiners, because these examiners are limited to searchable databases of written documents.

However, competitors and other parties are not so limited, and if your patent goes against their interests, it is safe to assume they will be on the hunt for any prior use that might have occurred, to use as ammunition in opposition or other invalidation proceedings, or as a defence in infringement or enforcement proceedings.

The classic case in the UK is Windsurfing International Inc. v Tabur Marine (Great Britain) Ltd, where the alleged prior use related to a sail board built by a 12 year old boy. The boy used his sail board in an isolated coastal inlet. There was no evidence that anybody had observed this, but the judge concluded that the use of the sail board was public in the sense that it had been potentially visible to anyone nearby, and the patent in question was invalidated.

What this means for the renewables sector is that testing and experiments conducted before filing a patent application, in such a way that there is the potential for them to be observed by a member of the public, could count as an earlier public disclosure and have the potential to render the patent invalid.

The best solution is to file a patent application before you start testing in public. By this stage inventors will generally have a good idea of how the invention is going to work, and are in a position to provide the necessary details. However, anyone who has been involved in the patent process will recognise that it can be a minor, but ultimately critical, detail that secures a granted patent. Sometimes those details are only discovered during testing, so that filing (additional) patent applications after testing has started, might the only option.

For patent applications filed after public testing has commenced, the question is, to what extent does this prior use give away the invention?

In general, if a machine is displayed or operated where it can be seen by a member of the public, and they are not bound by secrecy, then all information which our notional skilled person might be able to glean from what they can see is regarded as being publicly disclosed. However, for a disclosure to destroy the novelty of an invention, it also has to be “enabling”. That is to say, it would have to be possible for the skilled person to actually reproduce the invention from what they have seen. So, for example, an invention relating to the shape of a turbine blade would run into prior disclosure problems if the relevant parts of the blade were visible to the public during testing. On the other hand, an invention relating to some hidden internal part to which the public do not have access, is likely to be OK.

Of course, patents are territorial rights, and patent law does vary from country to country. In the US, for example, applicants benefit from a grace period, which means that inventors’ own disclosures made in the 12 months preceding their patent filing date do not count against them. However, it is necessary to be cautious, because prior public use can count against you in some form in most patent systems around the world.

To sum up, it is best to maintain secrecy around a new invention for as long as possible. However, when it is necessary to move to public testing, a patent application should be in place to protect the fundamentals of the invention, before that testing takes place. After testing has started, more patent applications can still be filed to protect new aspects that arise, but caution should be applied where those aspects might have been observed by a member of the public. In practice, the best filing strategy will depend on multiple factors, including the nature of the invention itself, the details that are available, and the point at which it is necessary to move to public testing. At Reddie & Grose our multidisciplinary teams of experienced patent attorneys are well placed to advise on developing bespoke filing strategies that meet the needs of individual companies.

This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.

Georgina Ainscow
Senior Associate
About the author

Would you like to know more? You can talk to Georgina Ainscow who will be able to help. Call +44 (0)20 7242 0901


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