The Application Of Doctrine Of Estoppel In Judgment Of Patent Infringement

Estoppel is an important principle in judging patent infringement.Some developed countries,especially the United States have formed a completely theoretical System.In china, law and legal interpretation about estoppel still does not legislate.Nowadays,estoppel has been acknowledged and applied in judging cases in our country,its application scope and frequency doesn't match the importance.Judicatory practice shows that the estoppel has not been widely and successfully used in patent infringement cases because of ambiguous definition and lack in patent law.Estoppel is still backward in our country compared to the developed countries in practice and theory,and doesn't fit the actuality of the patent development.The thesis begins from a recent adjudge of United States and analyses the basic concept of the estoppel,then analyses the proper concept about the patent law.This proper concept is the principle of prosecution history estoppel.It is that you can't demand to apply the principle of equivalent,because you have renounced the right in the past.In the following the thesis analyses the origin,theory and development of the principle of prosecution history estoppel. In the third part,the thesis analyses the function and application of the principle of prosecution history estoppel,its function is exhibition of restricting the principle of equivalent, explaining the scope of protection for patents,restricting the holder of patent;One of it's qualification is one has begin to act because he had believed your statement,and these action is impossible to cancel,the other qualification is that it is impossible to judge patent infringement by word.The statement and amendment would result in the restricting of the principle of prosecution history estoppel,the statement and amendment was formed in the procedure of application to patent.In the fourth part,the thesis explains the difference between the relation of the principle of prosecution history and the principle of equivalent.In the fifth part,the thesis introduces and analyses the difference between in the United States and Japan about the principle of prosecution history estoppel.In the sixth part,the thesis introduces the development of the principle of prosecution history estoppel in our country, and gives some advice about how to perfect the principle of prosecution history.The thesis insists on that we must perfect the law about the principle of prosecution history in the first. Only by perfecting the law,can we solve the discomfiture between the lack of law and the wildly applied in patent infringement cases,then we must accurately distinguish those statement and amendment that may be induce to apply the principle of prosecution history estoppel.We should distinguish different cases to apply the principle of prosecution history estoppel.In the end,the thesis gives the way to solve the cases.