How to Search Prior Art

Usually when people talk about prior art, they mean those patents which have been registered in patent offices and which are related to their project of interest. Because the patents registered in USPTO, EPO, PCT, and JPO covers more than 90% of patents filed worldwide, a prior art search is usually a search of patents that have been registered in those patent offices. You can use the old-fashioned manual search by visiting patent offices and various libraries to dig out the mountains of files to get the information you need. This was a typical search approach in the past, and even now some people still use such a manual search because they have the experience to know which mountains of files contain the required information.

With the rapid development of IT technology, on-line searching is becoming the dominant approach to search for prior arts on a variety of proprietary databases maintained by DIALOG, LEXIS, WESTLAW, and other commercial databases, in addition to the internet.

On-line searching is much more powerful, cost efficient, and thorough than old-fashioned manual searches. However, there are thousands of databases (for example, in Japan only there are more than 2000 databases) covering trillions of pieces of information, which make the search extremely difficult, if the searcher does not have enough skill and knowledge. Even if the searcher has all required search skills and knowledge in the associated areas, if he/she does not have the required language skills (English, Japanese, Chinese, etc.) or is not familiar with the area, a high quality search result can not be expected.

In our Japanese prior art search, we usually use following Japanese patent databases:

• Patolis: mainly for classification search;
• NRI: mainly used for full text search;
• JP-NET, mainly for file history/legal status search.

In our Japanese non-patent literature search, following databases are used:

• JSTPlus;
• JMEDPlus;
• G-Search; and
• A few other supplemental databases including READ, NINii, GENii, Kaken, etc.