Do’s and don’ts when filing a patent

One of the most important, yet also most daunting and complicated tasks in the process of bringing an invention to the market, is securing the appropriate patent. The process can take up a lot of time and resources, and failing to secure a fitting patent is one of the main reasons some inventions never reach the market.


Each year hundreds of patent filings cross our desks. This has given us a unique insight in the difference between a successful patent application, and an unsuccessful one. In this NLC knowledge paper we will highlight some of the most common flaws we see as well as share advice on how to avoid these.

1.The product already exists

Surprisingly often the product does already exist, but is just obscure. This is a direct indication that the need for the product may not be that pressing. Therefore, before continuing the search for ways to launch your product despite a similar product already in existence, it could pay off to thoroughly research the reasons the existing product has not been successful. Do any of these apply to your product as well? Search engines and patent databases like Google Patents or Espacenet can be a good starting point.

2. The invention has already been patented or published about

There is a distinct difference between this, and the problem discussed under point 1. In the first example we talk about an existing product, whereas this relates to an existing patent, or publication. We have seen multiple cases where the problem an invention seeks to address, had already been solved many years ago in the same or a similar manner.

A good example of something we encountered was a supposed novel type of surgical scissors where the exact same solution was patented twenty years earlier, but had never made it to market. As with point 1, this is often an indication that the problem is not sufficiently pressing, or the solution lacks commercial viability.

3. The invention is not patentable because it does not contain an inventive step

We often see that people make the mistake of thinking that combining common technologies and applying them to a new domain is patentable. This is however not the case. In order for your patent application to be successful, there needs to be an inventive step, a new technical measure that delivers a truly novel benefit. The step does not need to be complex, it can even be trivial, but it must not be obvious. It has to be such a measure that when someone ‘skilled in the art’ would encounter the same problem, this expert would typically not come to the same solution.

To illustrate this; we have reviewed several patent applications on hyperspectral imaging. In itself, this is not new technology, and applying it to a specific new field where it has not been used before – for example, perfusion surrounding sutures to reconnect intestines – does not constitute an invention.

4. Rating your chances of persuading the patent examiner after their first refusal too high

Understandably it can be difficult to be objective about one’s ‘invention’. Particularly when point 3 applies and the technology does already exist, but is merely combined or applied in a different way. Though there are many grey areas and one can indeed argue about the examiners interpretation, their opinion carries the most weight at the end of the day. If he/she is not convinced there will be no patent. If the examiner sees a way forward they will typically say so, so it pays off to look carefully at the remarks the examiner makes.

5. Publish the invention before the patent is filed

You cannot patent something that has been published about already. We have an example from one of our own ventures where a patent was filed on a certain aspect of a biomarker panel that was published shortly before. Luckily in this case, the filing was within the grace period for US filings, though this grace period is not applicable in Europe. Also note that any release to the public in any way, shape or form, e.g. a speech at a conference or a post on a bulletin board, counts as a publication.

Though companies have learned to be very diligent when it comes to publishing anything that may contain patentable content, universities – facing pressure to publish – are sometimes not. When working with a knowledge institution like a university, research center or technology transfer office, it can make sense to discuss this topic at an early stage.

6. Filing the patent too early, making it impossible to add key information later on in the process

A lot of people are not aware that once the patent is filed material changes cannot be made anymore. The only way around this is refiling, which is costly and in turn creates the risk of the newly filled patent being too similar to the patent filled in the first place and therefore getting rejected. You need to make sure that you are far enough down the line to get the details right – but not wait too long and risk someone filing a patent or publishing about it before you.

7. The patent does not cover the essence of the product

When a patent is filed on part of a product, but that product evolves into something else, the patent might not cover the essence of your product anymore. Or the other way around, an essential element of the granted claims is missing from the final product.

We have had the case where an implant was only covered if it included an active biocidal compound but the envisaged product did not. The result was a patent that did not cover the product.


How can you improve your filings?

Having discussed some of the most common problems we often encounter during the patent process for our ventures, below we provide some steps to take and questions to ask yourself before pursuing your patent application.

  • Check the market you want to introduce the invention to very thoroughly before applying for the patent. Are there any old patents or publications that solve the same problem? If there are, examine carefully why they have not entered the market. It might be that there is no market for this or it is not really an unmet need.
  • Be very aware of – and critical towards – your own bias. Read the evaluation of the examiner very carefully, do not convince yourself against better judgement that after a critical review, you still have a good chance of securing the patent.
  • Ask yourself if your invention is actually innovative. The technical measure you are trying to patent does not need to be complex, but it does need to add something truly new. If not, you are dealing with an existing technology that you are trying to apply to a new case and this is not patentable, so make sure the invention you want to patent qualifies as innovative.
  • Make sure you have thought about the future of your invention thoroughly. What product is it going to be when you introduce it to the market? Which problem are you trying to solve, and what will the solution be exactly? If this is not yet clear enough, or if it might still change over the course of the product development, it is often better to wait, so you can make sure you have a fitting patent for the right product and market.

Securing a strong patent can be a difficult process. At NLC, being the European Healthtech Venture Builder, we assess the protectability of many inventions on a daily basis, and we have built over 40 healthtech ventures to date. If you want to discuss your invention with us to see if we can help you bring it to the market, feel free to contact us via


Willem Fontijn – Technology Strategist


NLC has been excited from the very first moment we talked about our invention: the Concord Birth Trolley. But they also challenged us with questions that were new to us. Above all, NLC has matched us to a passionate entrepreneur. Without NLC, we wouldn't be able to improve birth for vulnerable babies as we are today.”

Alex Vernooij
PDEng, CTO at Concord Neonatal

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