The importance of maintaining secrecy before filing for a patent

Innovators developing new technologies have plenty to think about, and maintaining secrecy is not always top of the list. However, a recent case (Claydon Yield-O-Meter v Mzuri) shows how important it is to take care over this to avoid losing patent protection altogether.

The prototype test

The patent in question concerned agricultural technology, although the same principles will apply to other kinds of inventions. Here, the inventor of a new seed drill tested a prototype on private land before filing for patent protection. The innovative seed drill allowed for the planting of seed in a way intended to reduce soil erosion - “conservation tillage”. The inventor obtained patent protection, and his company, Claydon, brought infringement proceedings against Mzuri relating to their ProTil seed drills. Mzuri argued that the patent was invalid due to earlier disclosure of the invention through the prototype testing.

The prototype was tested over two days in 2002. Although this took place in a private field, there was a public footpath nearby with occasional viewpoints into the field. No one actually saw the testing, it seems, and those involved said that they would have stopped the process if anyone had been seen on the footpath. However, the mere possibility was enough to invalidate the patent. If the patent had been valid, Mzuri's products would have infringed.

How to avoid the problem

Clearly this was very disappointing for the patent owner, and many might consider it rather harsh. What can innovators do to protect their position and avoid this kind of problem?

  • Inventors need to be extremely careful as to where and how they test their inventions before they have filed a patent application. Use of a completely enclosed area, or effective restrictions on public access to viewpoints, would have helped the situation here.
  • Where viewers are expected to be present, confidentiality obligations should be imposed on them (a non-disclosure agreement, for example).
  • Remember that it is the possibility that the invention will be seen rather than whether someone actually does see it that matters. The problem arises where a suitably skilled observer could have seen prototype testing, in a situation where they were not subject to appropriate restrictions. 

Find out about our intellectual property services here.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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