With the development of industry and technology, patent infringement disputes become very common while competitors strive to occupy as big a proportion of the market share in the relative industry as possible. For a business entity, attention should be paid not only to the enforcing of its patent to stop a competitor's infringing upon the patent but also to the defending against the enforcement of a patent by the competitor. For a business entity involved in a patent infringement lawsuit, there are some defences to consider protecting its lawful rights and interests against the plaintiff's allegation of patent infringement. This article aims to give a brief introduction to some of the optional defences, strategies and relative procedures for a defendant in a patent infringement lawsuit.
Invalidity defence
Invalidity defence is one of the most commonly and firstly used defences made by a defendant in a patent infringement lawsuit. By the invalidity defence, two goals may be sought for i.e. having the patent invalidated completely or partly and making the claims of the patent to be limited further or narrowed down in scope and/or clarifying the protection scope of the claims of the patent.
To make the invalidity defence, an invalidation request against the patent is filed with the Chinese Patent Office rather than simply arguing invalidity of the patent before the court handling the patent infringement lawsuit. It would be preferable for the defendant if the invalidation request is filed within the time limit for responding to the plaintiff's complaint. With the invalidation request being filed with the CPO timely, the defendant may file a request for staying the trial of the patent infringement case with the court. If necessary, the court may stay the trial of the patent infringement case in order to avoid a scenario that the court makes a decision of finding infringement upon the patent but later the CPO makes a decision of declaring the patent invalid. According to the Chinese judicial practice, if the CPO makes a decision of invalidating a patent asserted by the plaintiff in the patent infringement lawsuit, the court may simply dismiss the lawsuit. However, the patent right owner may appeal the CPO's decision of invalidating the patent to Beijing Intellectual Property Court in the first instance and further appeal to the Supreme People's Court in the second instance. If CPO's decision of invalidating the patent is finally revoked by the Court, the patent right holder may file the lawsuit alleging patent infringement again.
There is a list of reasons on the ground of which a request for invalidation of a patent right can be filed. A patent right can be declared invalid if it falls in any of the following circumstances: lack of novelty; lack of inventiveness; lack of practical applicability; an invention that contravenes any law or social moral or that is detrimental to public interests; violation of confidentiality examination; inconformity with the definition of invention, utility model or design; belonging to subject matter ineligible for a patent right; amendments going beyond the scope of the initial disclosure; lack of support by the specification or failure to clearly to define the protection scope; failure to record technical features indispensable for solving the technical problem; and double patenting etc. Among these reasons, lack of novelty and lack of inventiveness are the most commonly used ones, but some of the remaining reasons such as lack of support by the specification, failure to clearly define protection scope unclear and amendments going beyond the scope of initial disclosure and failure to record technical features indispensable for solving the technical problem are also useful in some cases.
Sometimes it may be difficult to find a prior art document of category X which deprives claims of a patent of the novelty and prior art documents of category Y which in combination deprive the claims of the patent of inventiveness and the claims of the patent are not declared invalid on the ground of lack of novelty or inventiveness. There is still a possibility that through the procedure of invalidation request against the claims of a patent on the basis of the optional reasons, the claims of the patent are further clarified or narrowed down in protection scope either by amendments to the claims or observations about the invention creation claimed in patent made by owner of the patent right during the procedure of examination of the invalidation request.
Non-infringement defence
For non-infringement defence, all elements rule should be considered firstly. To find infringement of a product or a method upon a claim of a patent right necessitates that the product or method contains technical features identical or equivalent to all the technical features described in the claim of the patent, and no infringement of the product or method upon the claim of the patent can be found if there is one or more of these technical features in the claim of the patent for which the alleged infringing technical solution contains neither technical feature which is identical nor technical feature which is equivalent to the said one or more of the technical features as described in the claim.
Secondly, doctrine of equivalent should be considered. It is not unusual that the alleged infringing product or method differs from the technical solution defined in a claim of a patent and one or more technical features of the latter are not present in the former. In such case, doctrine of equivalents should be considered and the crucial issue is whether there is an infringement on doctrine of equivalent, i.e. whether the alleged infringing product or method has a corresponding technical feature which is determined as equivalent to the technical feature of the technical solution of the claim that is not present in the alleged infringing product or method. According to the judicial interpretations on patent infringement case trial issued by the Supreme People's Court, an equivalent technical feature in an alleged infringing product or method means the feature that uses substantially identical means, realizes substantially identical function and achieves substantially identical effect as the technical feature included in the technical solution of the claim of a patent right which is not present in the alleged infringing product or method, and that an ordinary technician of the pertinent field may associate easily with this technical feature without creative work when the alleged infringement occurs. In short four requirements i.e. triple substantial identicalness plus easy association should be met. With non-infringement defence, the first step is to find at least one technical feature of the technical solution of a claim of a patent right that is not used by the alleged infringing product or method. The second step is to argue that at least one of the four requirements are not met, while the plaintiff argues to the contrary. If successful, one such technical feature solves the whole lawsuit.
Thirdly, file wrapper estoppel may be considered, in arguing for non-infringement on doctrine of equivalent. According to the judicial interpretations of the Supreme People's Court, where a patent right holder reclaims a technical solution, which the patent applicant or patentee has abandoned through an amendment of claims or specification or through observations in the patent prosecution or invalidation procedure, in the scope of protection of a patent in a patent right infringement dispute case, the people's court shall not support it. With this principle, if the patent right holder argues that a technical feature in the alleged infringing product or method, which differs from and corresponds to the technical feature in the technical solution of the claim of the patent and which has been abandoned during the patent prosecution or invalidation procedure, is equivalent to that particular technical feature in the technical solution of the claim of the patent, this should not be supported.
Attention should be drawn to another principle which limits the application of the file wrapper estoppel. According to the interpretations of the Supreme People's Court, where a patentee proves that any restricting modification or observations to the claims, specifications and the attached drawing that have been made by the patent applicant or patentee in the prosecution of patent or invalidation examination procedure of the patent have been explicitly negated, the people's court shall determine such modification or observations do not lead to the abandonment of the technical solution. In view of this, all of the documents in the file wrapper should be studied completely and carefully when file wrapper estoppel is to be applied.
Prior art defence
According to the Chinese Patent Law, in a dispute over patent infringement, if the accused infringer has evidence to prove that the technology or design it or he exploits is an existing technology or design, no patent infringement is constituted. According to the judicial interpretations of the Supreme People's Court, if all the technical features which are alleged to fall into the scope of protection of a claim of a patent are identical to or are not substantively different from the corresponding technical features of an existing technical solution, the people's court shall determine the technology implemented by the alleged infringer as an existing technology. It can be known that for prior art defense, the comparison is made between the alleged infringing technical solution and the technical solution in the prior art with respect to the technical solution of a claim of a patent, rather than a direct comparison between the technical solution in the prior art and the technical solution of a claim of a patent, which is made in examination of novelty of the claim of the patent.
Prior use defence and legal source defence
Prior use defence and legal source defence are not so commonly used as the above three defences, a brief introduction is given below. For prior use defense, if the defendant has made or used a product or a process respectively, which fall in the protection scope of a patent, or has made necessary preparations for making such a product or using such a process prior to the date of application of the patent, the defendant may continue to make such product or use such a process within the original scope, which is not considered as infringement upon the patent. However, the continuing making of the product or using of the process is limited to the original scope of the defendant's making and using before the application date of the patent and no expanding of operation scale is allowed, this is apparently not the most preferable defense for the defendant.
For legal source defense, whoever uses or sells a patented product without knowing that the product was produced and sold without permission of the patentee or a product directly obtained from a patented process for the purpose of production and business operation is not required to bear the liabilities for compensation provided that it or he can prove that the product is obtained from a legal source. For this defense, the defendant should provide a complete chain of evidence to prove the products are obtained from a third party in a normal business mode and the criterion to the evidence is strict. If this defense is supported, the seller of the product should still cease to sell the product anymore, but the user may continue to use the product if the user of the alleged infringing product produces evidence to prove that it has paid the reasonable consideration of the product.
Given above is a basic introduction of some of the optional defenses that may be considered by a defendant in a patent infringement lawsuit. In practice, the situation is usually complicated, and a comprehensive study of the case is necessary to make a strategy to defend in the patent infringement lawsuit to achieve the best possible outcome.
(First published in Managing IP: 2020 China IP Focus )
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
