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Patent Search & Analytics

The When, How, and Why of Patent Validity Search

By June 23, 2021No Comments

In order to patent an invention, it must be novel, non-obvious, and useful. A patent examiner determines whether or not an invention fits these criteria with a prior art search and industry knowledge, as well as the language of the patent claims themselves. However, these criteria are somewhat subjective, and confidently granting a valid patent requires an incredibly detailed look at relevant patent claims and technical literature. For these reasons, some granted patents are stronger than others. A patent validity search (also known as a patent invalidity search) may be required later on in the life of a patent to determine whether or not it is, in fact, novel and non-obvious. 

When to Conduct a Patent Validity Search

A patent invalidity search is—in many ways—comparable to a patentability search as well as the rigorous patent examination process. However, a validity search looks for relevant, invalidating prior art after a patent has been granted. The party pursuing the patent search may be the patent holder or a third-party organization with a vested interest in the results of the search. There are multiple reasons an entity may be interested in knowing whether a patent is valid or invalid. 


A patent validity search is conducted defensively when there is already a concern of infringement. In this case, there may be a question of whether a patent is infringing on an earlier patent, or whether an unpatented technology is infringing on a granted patent. No matter which side of the court you’re on, you’ll likely want a comprehensive patent validity search to back your case. 


Hopefully, your patent validity analysis is more proactive. A validity search can be done when you’re looking to evaluate the strength and value of a patented technology. Knowing whether or not a patent is valid can help you strategically monetize it via licensing, sale, or even mergers and acquisitions. 

How to Do a Patent Validity Search

First, a searcher must determine the patent claims’ priority dates. Under the first-to-file system, this is generally the filing date. Then, all relevant prior art, including patents and non-patent literature, must be identified. The search should include prior art from around the world, not just the country the patent is in. This process begins with the prior art identified in the patent application and by the patent examiner. It can then be expanded to include tangentially related yet uncited (and perhaps undiscovered) literature that may invalidate the patent claims. 

This research is then passed on to an attorney for analysis of the validity of the patent. The attorney will compare any newly discovered prior art to the patent’s Allowable Subject Matter and offer an opinion as to whether the patent is valid.