Same patent by others in different country?

If an earlier applicant obtains a patent first in their own country, can others subsequently patent the same invention in a different country? The simple answer “should” be no. The reality, however, is more complicated. What happens in the real patent world does not always follow what should happen.

Various factors come into play. Are we dealing with design or utility patents? How thorough of an examination will be undertaken by the foreign patent examiner? Does a particular foreign patent office grant patents without any examination (e.g., utility models in Asia)?

Prior art is international

Nearly every patent office throughout the world will examine a patent application before allowing it. After a patent application is filed, a patent examiner will be assigned to review the claims and then search the prior art.

The patent examiner can, and sometimes does, search for prior art internationally. The examiner is not limited to prior art in their own country. In other words, the prior art effect of a past patent filing extends beyond the geographical boundaries of the country in which the patent was issued or published. For example, a US patent or patent publication would serve as prior art against subsequently filed patent applications not only in the US, but also in foreign countries. Similarly, a foreign patent or publication would also serve as prior art against a subsequently filed US application. Prior art, therefore, has a worldwide effect in blocking future applicants from patenting the same thing.

When patent rights are described as territorial, the geographical limitations apply only to an issued patent’s enforceability. A US patent can be enforced only in the US. This means that the patent owner can stop others from making, using, selling or advertising the patented product or process in the United States. The blocking impact of prior art against future patent applications, however, is worldwide. A prior patent in one country, therefore, could and should be an obstacle against subsequently filed applications in all countries.

What if later filed patents in other countries are not the same?

If prior art has no geographical boundaries, then why do others seem to get away with patenting a similar invention in a different country? One possible explanation may be that the the claims had been modified in the later patent application. By amending the claims, later applicants can argue that their patent application does not cover the same invention shown in the prior art patent.

Suppose you own a US patent and a foreign manufacturer wants to patent the same invention in their country. Would it be more likely that they would apply for the identical invention or for a modified invention?

Another possibility is that the patent examiner did not conduct an international search of prior art. US patent examiners, for example, typically focus on US patents and patent publications. Occasionally, a US examiner might find a foreign patent reference and refer to its English abstract.

Utility model: skipping patent examination altogether

Some foreign patent offices offer the option of a utility model, an automatic grant of patent rights without examination. It’s called a utility model which is popular in Asian countries, such as Taiwan, China and Japan. The utility model system enables an applicant to get instant patent rights without a prior art search. If and when the utility model is subsequently challenged, a substantive review would then occur which may lead to the cancellation of the utility model. A utility model can be thought of as a temporary patent.

Defensive purposes for filing patents

The worldwide blocking effect of patent applications adds to the incentive to apply for patents as a defensive measure against future filers. Even if the success of a utility patent application is unsure, the publication of the patent application can serve to hinder later filers from patenting the same invention around the world.

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Vic Lin

Startup Patent Attorney, Cofounder at Innovation Capital Law Group
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