Study On References Of Doctrine Of Equivalents To Inventive Step Determination Principles

Doctrine of Equivalents is a concept regarding patent infringement determination, while Inventive Step, also called non-obviousness is a concept applied in patent examination procedure. These two concepts are employed independently for a long term. In practice, one-by-one feature determination is commonly implemented according to Doctrine of Equivalents. In this way, each feature of the sued subject matter is compared with a corresponding feature of subject matter in an involved patent. Thus, it is rather difficult to practice Doctrine of Equivalents. Courts or judges often made conclusions different from each other at all on the same case, which takes immensely adverse influence on development of Doctrine of Equivalents. This paper establishes relevance of Doctrine of Equivalents and Inventive Step for referring to various experience of Inventive Step in patent infringement determination, and addresses an issue of an infringement determination according to Doctrine of Equivalents, in which the sued subject matter as a whole is compared with subject matter in a patent claim. Further based on the relevance of Doctrine of Equivalents and Inventive Step, a variety of usual methods and conceptions in determination of Inventive Step, such as a ghost three-step determination method, a scope of ghost prior art, a ghost person in the pertinent art, technical guide and so on, can be applied in the patent infringement determination according to Doctrine of Equivalents, achieving desired certainty in application of Doctrine of Equivalents. In application, above all, a scope of ghost prior art and a ghost person in the pertinent art is determined for establishing a certain determination standard. During patent infringement determination, technical guide is considered to determine whether or not the sued subject matter can be reached by combining the involved patent with the ghost prior art. Referring to determination of inventive step, some auxiliary determination methods, such as overcoming prejudice, solving long-standing problems, incurring unexpected technical effects and achieving commercial success, might be applied in patent infringement determination. In addition, prosecution history estoppel can be applied to limit the patent's border based upon applicant's concession during patent prosecution. Also, Principle of Superfluity Establishing could be applied to prevent against inappropriate limitation on the patent owing to inadvertency. Based on the relevance of Doctrine of Equivalents and Inventive Step, defense depending on prior art limits a certain ghost scope of prior art. Thus this measure could assist in patent infringement determination to achieve a certain and accurate conclusion.