I meant to produce a tool in China and that the product is for sale in a European Union. I learned that this tool patented and now I have a problem to realize my idea. A company that can make that tool has ISO9001 permission but I'm afraid to sell a tool that is patented in the United States because it is a patented product. The Chinese company would have produced a tool and if I drew attention to a patent but I am afraid that no problems occur if the product I sell. Pat is 75 years old and now the new owner of the patent and I'm not sure whether the term of the patent expired in view of that is that old. The new owner of the patent (which is little changed and the same number of the patent) is of entirely application 15 years ago. I'm a little confused when I saw that even in this patent, there are more companies with their logo? What does that mean, the same patent but different companies have logo. Please, if you take the time and write to me if you have something to do in these situations. Thank you in advance

  • It would be good if you could list the patent #'s
    – 3dalliance
    Jul 13, 2016 at 13:41
  • 2
    Please list the patent and we can help you check its status. If it really is 75 years old, it is certainly expired and will not keep you from using the idea. There may be other patents however.
    – Eric S
    Jan 13, 2017 at 2:41

1 Answer 1


Technology can be licenced from expired patents but it is rare. Usually in the form of trade secrets that have been held back from the patented material, eg: Source code of a patented algorithm. It also simply may mean the these other brands have used the technology of an expired patent which is totally legal and even encouraged by the technology broadcast function of the world patent system.


Be careful that there is not new patents issued that would prevent your freedom to operate or practice the invention commercially. Check the other brands to see if they have patents or pending patents.

  • 1
    Source code of a patented algorithm would generally be protected via a copyright registration. However, @3dalliane, since patent specifications and claims have to be fully enabling, you cannot hold back enabling details as a trade secret. If the information is non-enabling, then it would have been considered obvious from prior art.
    – Kane Chew
    Jul 7, 2018 at 19:58
  • if the specification does not enable making and using the claimed invention then the claims suffer from lack of a written description. This is not at all related to prior art issues.
    – George White
    Aug 31, 2019 at 19:05

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .