Research On The Application And Restriction Of The Doctrine Of Equivalents

The fundamental goal of the patent system is to protect the patentee's lawful rights and interests, to encourage invention-creation,and based on which to promote the development and innovation of science and technology through making public the scheme of patented technology.However, various patent infringements hinders the realization of this goal, especially the infringement under the doctrine of equivalents. The doctrine of equivalents was established in America about two hundred years ago. Under the influence of America, many developed countries, such as England, Germany and Japan have adopted the doctrine of equivalents in the patent infringement action. So has the World Intellectual Property Organization. So, the doctrine of equivalents has become an international principle on judging the infringement of patent.In the United States, the doctrine of equivalents is not a statutory provision in the patent law, but a set of rules established by a series of cases when courts decide infringement of patent U.S. cases discussed many issues in a deep going way concerning the doctrine of equivalents, is worth of Chinese scholars and judges to take reference from them. Further studies on the DOE does good to set the problem of that kind by offering realistic theories for our legislative and judicial circle, and is of great importance to establish the idea of balancing of interests, widen the realm of intellectual property rights, and promote the development of the patent law, even ,in a sense, the whole intellectual property jurisprudence.A patent claim has two functions: defining an invention and providing a public notice. A patent claim is a key issue in deciding whether an infringement of the patent occurred there. When the determination of patent infringement becomes more and more difficult and complex, the doctrine of equivalents gives the judge a good law foundation.Though its application can protect the patentee's interest effectively, its improper application can spoil the double functions of a patent claim. Thus, there will be something uncertain with the result of Patent Infringement judge and finally infringe upon the public interest. 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 interest of the public, we should not only limit the application of the doctrine of equivalents strictly from the inner aspects, such as its standard, method, etc, but from its outer aspects, such as Estoppel, Prior Art Defense.This paper is a detailed introduction and analysis on the application and restriction of the doctrine of equivalents. The whole article consists of four chapters. Chapter one is a introduction of the Doctrine of Equivalents in Patent Infringement. Firstly it clarifies the necessity of the Doctrine of Equivalents, and determine the the patent claim scope and the patent protection scope. Secondly, it introduces the concept of the Doctrine of Equivalents. Thirdly, it introduces the establishment of the Doctrine of Equivalents in U.S.. Chapter two is to analyze the applicability and the constitutive elements of the doctrine of equivalents in the litigation about patent infringement, such as the"function-way-result"identity test,"element by element"test, etc.. Chapter three is about the restriction of the doctrine of equivalents, such as prosecution history estoppel, Prior Art Defense, and the Public Dedication Doctrine. In the two charpters , particular research is made on the latest cases of the USA to act as an accordance in discussing some issues in detail in the patent infringement determination under the doctrine of equivalents.And, it also introduces the present situation about legislation and administration about DOE in China. At last, it gives several pieces of advice to improve our DOE system on base of research in the previous contents.