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What does it mean when an algorithm is patented? Am I allowed to use it as long as I am not making money out of it? I am asking because I am working on a project and I happened to discover a feature detection algorithm that I want to implement, but then it is patented by someone. Can I use the algorithm? It is for a school project


migration rejected from Dec 4 '13 at 13:13

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closed as too broad by MichaelT, gnat, GlenH7, Robert Harvey, Bart van Ingen Schenau Dec 4 '13 at 13:13

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First of all you should state your jurisdiction. In Europe software patents are much more restricted(in theory they don't exist at all here, but there are workarounds) than in the US. – CodesInChaos Feb 13 '11 at 8:59
You should have a look at this question:… – gablin Feb 13 '11 at 10:17
As is, this is not a real question, because there's no hint of jurisdiction. Patent law varies between countries, and even if I knew the laws well for all the countries I couldn't answer this question. – David Thornley Oct 11 '11 at 22:01

4 Answers 4

In the UK a purely mathematical 'invention', which is what an algorithm is, is exempted for patenting. So, just because you have read somewhere that an algorithm is patented, you need to be aware of the true legal situation in the country where you distribute any software. Much internet discourse (in English) is, understandably enough, dominated by the US legal position, but that is not a guide to the universal position.


I'm not suggesting you do this as a matter of course, but I must disagree with some of the other replies here.

A patent owner of anything has an exclusive right to that thing for commercial exploitation, for the period of the patent.

If you use a patented thing but make no commercial gain for yourself AND ALSO you do no harm to the commercial gain made by the patent owner, then it should be no big deal. (Or to put it another way, their chance of discovering you is pretty much NIL, and if they did the chance of a successful legal action is pretty much NIL because there was no loss involved.)

So if you can be really really sure of the conditions (ie that your purpose will never lead to a further exploitation which would cause loss to the patent owner) then you can probably make use of the patented thing. Just be very very sure of yourself.

If the thing you do could conceivable ever be used commercially to make a thing that is sold for money, then you are on shaky ground. That would imply a possible loss for the patent owner.

The trouble with asking is that they may say no. Not asking (and knowing you infringe) will get you some very big damages in a US court - if the legal action succeeds.

This whole topic is not as black and white as it might first appear.


I guess it depends on the owner of the patent. If in doubt contact him and ask for permission to use it.

Some patents for example exist, but are not "used". For example there is a patent on QR-Codes, but the patent owner does not use it. Therefore everybody is free to use OR-Codes. In other cases patent owners may choose to sell it, if it used commercially and give it away free for non commercial projects.

If in doubt use a workaround or ask for permission. If the project is just used by an closed users group you may use the algorithm and hope for the best.

What if the patent is owned by the University of British Colombia? – Hien Feb 13 '11 at 9:07
As i said, if you want to be sure, ask for permission. I guess they will allow it. But we can't say you anymore. If in doubt write them an mail. – user17124 Feb 13 '11 at 9:16

A patented algorithm is owned by the patent holder, and any use whatsoever is subject to their approval. In practice, I doubt anyone will sue you for using their patent in a school project, but the law is definitely not on your side.


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