Research On The Doctrine Of Equivalents In Patent Infringement

The doctrine of equivalents is an important judicial principle which was put forward by American Court in the practice of Patent Infringement. It has a history of nearly 200 years and it has grown into a rather perfect theory system. The doctrine of equivalents has being accepted word-widely under the influence of America. The Supreme Court of China set some principled regulations over it in 2001, too. Though its application can protect the patentee's interest effectively, its improper application can spoil the double functions, defining invention and informing public, of patent claim. Thus, there will be something uncertain with the result of Patent Infringement judge and finally infringe upon the public interest represented by defendant. Therefore, in order to apply the doctrine of equivalents objectively, definitely, fairly and reasonably and to make a perfect balance between the patentee's interest and the public's interest, when applying it, we should not only limit strictly from the inner aspect, such as its standard, method, etc, but from its outer aspect such as Estoppel, Prior Art Defense.