The patentee who wants to enforce his patent in China should pay attention to the principle of allocating the burden of proof which is one of the most important factors affecting whether the intended goal could be achieved in patent infringement litigation.
Generally, the basic principle adopted for allocating the burden of proof in patent infringement litigation is "Burden of Proof Borne by Claimant". Therefore, in patent infringement litigation, the patentee bears the burden of proof. The standard of the principle is high probability criterion, i.e., the fact can be determined by the Court if the evidence provided by one party can prove that the fact involved has happened with high probability. However, it doesn't request for a perfect evidence chain to be provided by the patentee, as long as there is a higher possibility to enable the judge to affirm the fact asserted by the patentee based on the existing evidence and in connection with the life experience and transaction practice etc. When there is no evidence or the evidence is not strong enough to support the patentee's allegation, the patentee shall undertake unfavorable consequences, even the risk of losing the lawsuit.
An only statutory exception to the basic principle mentioned above is the provision for reversion of the burden of proof. But, the provision is only applied for the patent infringement case relating to a manufacturing method of a new product, i.e., the accused infringer should bear the burden of proof to prove the method he used is different from the patented method. Accordingly, applying the provision for reversion of the burden of proof requires two preconditions, i.e., the patent is a method patent and the product manufactured by the patented method is new. The provision for reversion of the burden of proof cannot apply for other types of method patents, such as application method, processing method, etc.
In practice, unfortunately, the patentee faces a lot of difficulties when collecting evidence in many special types of infringement lawsuits, and applying the principle of Burden of Proof Borne by Claimant will result in that the right of the patentee cannot be protected effectively. In recent years, with the increasing of IP protection in China, the Court assigns the burden of proof reasonably to the parties based on the actual situations during the trial of the infringement lawsuits, which alleviates the burden of the patentee to some extent and can be referenced by the patentee.
Hereinafter, based on some latest cases from the Court, the practice and tendency of the principle on how the burden of proof is allocated in Chinese patent infringement litigation will be discussed.
1. Case Relating to Large Scale Equipment Type of Products
When enforcing a product patent, generally, the patentee can collect evidence by purchasing the infringing product in the market. But for the large scale equipment, there are several problems as below when collecting evidence. First, due to the high price of the equipment, purchasing the infringing product brings severe economic pressure to the patentee. Second, some of the equipments are customized made, so it is hard to purchase it in the market via regular channels. Third, the equipment is usually controlled directly by the accused infringer, so the patentee can hardly obtain it. Accordingly, the patentees of such products can hardly collect the infringement evidence with the regular measures and then it's hard for them to enforce their own rights.
In Lupke v. Zhongyun Co., et.al, the alleged product is a part of a large scale equipment and cannot be obtained without disassembling the equipment, so it's hard for the patentee Lupke to obtain the alleged product in the market via regular channels. Because the infringers Zhongyun Co., et.al refused to provide the equipment drawings and refused the request for disassembling the equipment, the patentee failed to provide sufficient evidence to support his allegation after he had adopted many ways to prove the infringement facts. The first instance and the second instance courts both support the allegation of the patentee based on the existing evidence according to the provision of the Regulations on Civil Action Evidence issued by Supreme People's Court,Article.75, During the retrial, the Supreme Court held that,
"The equipment in this case is of high price and large size, and is actually controlled by the infringers, so there're lots of actual difficulties for the patentee to collect evidence by himself. The patentee could be believed to fulfill his responsibility if the ways he had adopted almost covered all the legitimate ways of evidence collection. The infringers should undertake the unfavorable consequences in the case that the patentee already provided the evidence as possible as he could and the evidence could preliminarily prove that the infringement fact is established; the infringers refused to provide the drawings of the alleged equipment and refused to cooperate on the identification without any justified reasons which made the identification couldn't be done; and the infringers did not provide evidence to prove that the technical solution of the alleged equipment is different from the patent and doesn't fall into the protection scope of the patent. So according to Regulations on Civil Action Evidence issued by Supreme Court, Article 75, it can be inferred that Lupke's allegation is tenable."
Finally, the Supreme Court rejected the retrial request of the infringers.
2. Case Relating to Manufacturing Method for Non-new Product
In the infringement actions referring to a manufacturing method for product, it's hard for people to learn the details of the manufacturing method adopted by the infringer, because the manufacturing method is generally used within the enterprise of the infringer. For most of the manufacturing methods for existing product, it's hard for the patentee to collect infringement evidence.
In view of the practical difficulties, the Opinions on Trial Functions into Full Play the Role of Intellectual Property to promote development and prosperity of socialist culture and promote the coordinated development of economic autonomy Issues drafted by the Supreme People's Court indicates that "In the situation that the product manufactured by the patented method is not new, the patentee can prove that the infringer manufactures the same product, but cannot prove with reasonable efforts that the infringer uses the patented method, according to the specific conditions and combining with the existing facts and daily experiences, if it can be determined that it is highly possible the alleged product is manufactured by the patented method, the patentee shall no longer be requested for further evidence, but the infringer shall submit the evidence to prove that its manufacturing method is different from the patented method in accordance with the relevant regulations of judicial interpretation on civil litigation evidence."
In Yibin Changyi Pulp Co., Ltd. v. Weifang Henglian Paper Pulp Co., Ltd., the dispute focused on how to allocate the burden of proof for parties due to the manufacturing method patent for non-new product. The plaintiff Changyi provided preliminary evidence to prove that the alleged method and the product manufactured by the alleged method are the same as the patented method and the product manufactured by the patented method. The first instance court assigned the burden of proof to the defendant Henglian in consideration of the above evidence. But the defendant refused to prove that the alleged method is different from the patented method, so the first instance court decided that the alleged method fell into the protection scope of the patent. The second instance court rejected the appeal of Henglian based on the same reason. During the retrial, the Supreme Court held that,
"Generally, the specific process steps or the data of manufacturing method can be learned only in the manufacturing site or by checking the production record. In the situation that the evidence on the manufacturing method of a product is fully controlled by the infringer, it's hard for the patentee to access the manufacturing site and production record to get the complete evidence on the manufacturing method. In this case, the Changyi has tried its best to prove the manufacturing method fell into the protection scope of the patent by using various ways. Meanwhile, the Henglian didn't cooperate with the court for the evidence preservation on the manufacturing method it controlled, which resulted in that the court could not obtain the evidence of the alleged method. Based on the above evidence and daily experiences, it can be inferred that the Henglian has a high possibility of infringement. In the case that the Henglian doesn't provide effective evidence to prove the manufacturing method it used is different from the patented method, the Henglian should undertake the unfavorable consequences."
The Supreme Court rejected the retrial request eventually.
3. Case Relating to Features Determined in Operation State
Regarding product claim, it's generally defined by structure features, but in some special cases, it can be defined by function features, effect features, method features, physical and chemical features or usage state features, and the like. When comparing these non-structural features of the infringing product with those of the patent, these features can't be reflected by the structure of the product, so generally it's hard for the patentee to determine if the alleged product falls into the protection scope of the patent before filing a lawsuit.
In Staubli Faverges Co., Ltd. v. Changshu Textile Machinery Co., Ltd., the patent related to rotating dobby. The claim of the patent includes a feature defining the working state of the actuator, which is "when said levers are engaged with said wedging surfaces, one of said lever is out of range of an actuator belong to said reading device". During the first instance, the court confirmed the alleged product had the same function with the function to be achieved by the patent and its structure was the same as the structure of the patent according to the demonstration and analysis. Therefore, it could be inferred that the alleged product had the above feature in actual operation. The first instance court held that the alleged product fell into the protection scope of the patent. After the defendant Changshu Textile Machinery appealed against the decision, the second instance count rejected the appeal based on the same reason.
It can be learned from the typical cases discussed above, the Court will assign the burden of proof reasonably between the patentee and the infringer based on the actual conditions. But above all, the patentee should try his best to take the responsibility of the burden of proof so as to make it possible for the court to shift the burden of proof to the infringer. Under the conditions that the patentees are not able to get the alleged product or access the alleged method, they should try their best to take various measures to enable the court to believe a high possibility of infringement.
Law of Civil Procedure, Article64, Paragraph1 stipulates: the parties have the responsibility to provide evidence for their claims.
<Several Provisions of the Supreme People's Court on Evidence in Civil Procedures, Article2, Paragraph 2 stipulates: where any party cannot produce evidence or the evidence produced cannot support the facts on which the allegations are based, the party concerned that bears the burden of proof shall undertake unfavorable consequences.
Civil Ruling (2012) Min Shen Zi No. 39 by the Supreme People's Court on December 18, 2012.
 The Article 75 stipulates: where a party makes statements for its allegations but fails to provide other relevant evidence, the allegations thereof shall not be affirmed, unless the other party so affirms.
Opinions on Trial Functions into Full Play the Role of Intellectual Property to promote development and prosperity of socialist culture and promote the coordinated development of economic autonomy Issues9drafted by the Supreme People's Court, No.18 (2011).
 The Civil Ruling Paper of Min Shen Zi No.309 (2013) by Supreme People's Court.
 The Civil Ruling Paper of Su Zhi Min Zhong Zi No.0290 (2012) by Jiangsu Province Supreme People's Court.
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.