Finding prior arts for a non-English patent

Finding prior art can be like looking for a needle in a haystack. Further, when one has to do it to find a prior art for non-English language patent, it becomes a bigger challenge.

Although we may find prior arts for non-English patents in an English patent, though it is always recommended to do an exhaustive search in the same language (non-English) patents as the possibility of finding linguistic synonyms and their equivalents becomes higher.

In general, the most Important non-English patent jurisdictions are China, Japan, Korea, Taiwan, Singapore, Germany and France. These countries publish high-end cutting-edge research literature on a huge scale.

Generally, the databases which are used for getting English translation for non-English prior art searches are Google Patents, Derwent Innovation, Questel Orbit Espacenet. As the English translations from different databases can be different in their sentence and word choices, it helps to read through all the versions and compare them with one another, giving us insights as well as some key keywords related to the idea of the invention.

For example: Translation of a Japanese publication (JP2016008417A) claims from Google patents is as below;

The same patent when translated through Espacenet gave us claims as;

Translation of the same from PAJ  showed different text with different sentence formation and the keywords as below.

In all of the three cases, the preamble of the Japanese publication is different since all the three different databases use their own translation engines.

Google Patents Espacenet PAJ
A latch mechanism that detachably locks the striker and has an operation receiving portion for releasing the lock of the striker; A latch mechanism having an operation receiving portion for releasably locking the striker and releasing the lock of the striker A latch mechanism having an operation receiving part for detachably locking the striker and releasing the lock of the striker


Also, the synonym of detachable is mentioned by Espacenet translation i.e. releasable. In the same fashion, other keywords and linguistic synonyms can be found. These synonyms therefore, can be used for performing a more exhaustive prior art searching.

Different methods which can be deployed to effectively find prior arts for non-English patents are

  1. When a relevant result has been identified, its citations are checked to identify more relevant prior arts. It happens that more relevant prior art is found, then it is checked why the prior art did not showed up in the initial search. It may be due to non-inclusion of relevant keywords or technology classes. Therefore, an iterative process can be deployed wherein keywords and technology classes are updated simultaneously.
  2. We should also use reverse search string strategy can be utilized i.e. converting the search strings into the language of the subject patent using translators and then searching them on the local language database or normal databases such as Google itself. For example,
    1. is one of the engines used for prior art search in the Japanese language,
    2. is the State Intellectual Property Office website of China,
    3. is a database for Chinese Academic Journals,
    4. is the official German register for patents, utility models, trademarks and designs.

The results obtained from such non-native language databases are then translated to English, for better understanding and comparison. Thus, the search is comprehensive, leaving no corner unscanned, yielding the best results.

  1. Further, in case the patent has images that clearly depicts the novelty of invention, then image analysis should be done as an important sub-part of prior art search process as images overcome any linguistic variations and interpretations.
  2. In any case, associates must be trained in specific native languages so that they can perform prior art searches in local language databases effectively.


Searching for prior arts in non-English language has its own challenges, though the process becomes smooth, efficient and fast with the combination of the right databases, experienced researchers and some smart tips and tricks. Nonetheless it is always better to have researchers who can deploy the strategies along with having proficiency in the language in which the patent is filed.


We at ResearchWire Knowledge Solutions, have associates that have proficiency in different languages and they deploy various search strategies to find most promising prior arts for any non-English language patent.

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