A defense against the charge of infringing a patent claim is to show that the existing patents is invalid and was granted in error; due to the existence of previously undiscovered prior art which proves that the claimed invention is not novel or non-obvious.
Why invalidate?
- Invalidity searches can be useful as a defensive tool when a company is concerned about infringing a particular patent
- An invalidity search attempts to uncover issued patents or other published prior art that may render a patent partially or completely invalid.
- In contrast, validity searches can also be used to invalidate an in-force patent thereby allowing a company to practice that technology without paying royalties to the firm that holds the rights to the patent in question
What is required to invalidate?
- Active or lapsed or expired patent/publication
- Non-patent literature
- Scientific literature
- Old sales catalogs
- Trade journals
- Conference etc…
- The most importantly the priority date of source document should be prior to the priority date of the patent to be invalidated, in case of US
- In case of German, the publication date of source document should be prior to the priority date of the patent to be invalidated
Summary
A validity search can serves as a basis for
- A legal opinion against infringement
- As a due diligence prior to selling or license a patent
- Practice technology without paying royalties, if invalidated
