Validity /Invalidity Search

A validity search is conducted after a patent issue, to find prior art that the patent examiner missed during the office action phase so that the patent or certain claims can be declared invalid. Such a search might be required for a number of reasons including litigation, valuation, licensing, etc.

A patent validity search (invalidity) focusing on Japanese is the most extensive and in-depth search we perform. Often a client comes to us after they have already performed thorough searches in English. Asian language, especially Japanese, usually is at the last phase of a validity search (invalidity) project because of language barrier and cost involved. However, the chance of uncovering good Japanese prior art is higher considering the fact that it is really not an easy task for the patent examiners and the English searchers to search Japanese documents at the previous stages. This is how we come to play such an important role. We work for attorneys, IP managers of multinational corporations for their litigation case relating to infringement, or patent valuation, licensing.

Before the search, we usually have to decide following aspects by consulting with our clients: claim interpretation, claimed features to be focused, cut-off date, previous search history and results, etc.

We often cover the entire body of potential prior art starting from the prosecution history / file history of the target patent, to Japanese (and/or Chinese, Korean) patent and non-patent literatures using commercial databases as the primary tools and official patent office database such as IPDL provided by JPO as useful supplementary sources.

Due to the huge number of patent documents stored at Japanesse Patent Office, and non-patent literatures stored at multiple information providers' databases such as JSTPlus, and also due to language barriers, Japanese prior art search is considered to be the most difficult one and is the most expensive one.

Validity search or invalidity search can be a long journey and a searcher can continue looking for a needle in a haystack till a useful prior art is uncovered or till the budget is exhausted.

Japanese patent databases and non-patent literature databases we often use

For Japanese patent, we usually use following databases:
1) Patolis: mainly for classification search;
2) NRI: mainly used for full text search.
3) JP-NET, mainly for file history/legal status search.

To reduce download cost for full copies of patent documents, we use a tool named GetIPDL to download full patent documents from IPDL provided by JPO, which usually can save quite a big expense.

For Japanese non-patent literature, we usually use:
1) JSTPlus;
2) JMEDPlus;
3) G-Search;
4) J-Global;
5) And a few other supplemental databases including READ, NINii, GENii, Kaken, etc.

We have a much higher success rate in uncovering relevant art in validity search than other firms. This is because we focus on Japanese prior art, which in most cases have not been searched by a patent holder before filing the patent, nor by the USPTO patent examiners before issuing the patent, due to the difficulties and high cost involved.

The average patent litigation costs are estimated to be $1 - 4 millions. Often a litigation takes years to settle. Therefore, spending a few thousand dollars in validity search at the onset of a litigation or licensing is a very good investment.

In a comprehensive invalidity search, a searcher may continue looking for a needle in a haystack till a useful prior art is uncovered or till budget or time is exhausted. We usually have to screen and review hundreds of even thousands of documents in local languages.


Japanese patent validity search is our more sought service. We have performed hundreds of invalidity searches for patent attorneys, IP managers of multinational corporations.