Allocation of burden of proof is an area of great concern in a process patent infringement dispute. In practice, the accused infringing process is usually strictly controlled by the accused infringer and hard to approach, which poses great challenges for a patentee of a process patent to produce evidence and enforce its legitimate right. Fortunately, a patentee of a process patent for manufacturing a new product doesn’t have to bother with producing evidence showing the defendant’s infringement, as the Patent Law and the Rules of Evidences in Civil Procedures both set forth that the accused infringer shall furnish proof to show that the process used in the manufacturing of its products is different from the patented process as long as the patentee can prove that the process patent directs to a new product and that the accused infringer have made identical products. However, a patentee holding a process patent for manufacturing a known (not new) product will not be so lucky. In his case, the patentee has to struggle with collecting evidence with respect to the defendant’s process, as no law or interpretation has specified the allocation of burden of proof in such circumstances so the general principle that “He who alleges shall bear the burden of proof” will be followed.TRIPS agreement provides a bypass for the patentee under the above situation by stipulating a presumption to be invoked and a reverse of burden of proof in certain circumstances. As set forth in Article 34, “members shall provide, in at least one of the following circumstances, that any identical product when produced without the consent of the patent owner shall, in the absence of proof to the contrary, be deemed to have been obtained by the patented process: (a) if the product obtained by the patented process is new; (b) if there is a substantial likelihood that the identical product was made by the process and the owner of the patent has been unable through reasonable efforts to determine the process actually used.” The judicial trial in China has explored the invocation of the presumptions in patent infringement disputes over manufacturing process of a known product. This article will provide a brief introduction to it.

Invocation of Presumptions

The legal basis for invoking a presumption lies in the general spirit when allocating burden of proof pursuant to the Civil Procedures; all parties in possession of evidence shall be obliged to provide evidence to prove facts, and the burden of proof shall be allocated to each party based on the principles of fairness, integrity and good faith to the extent that facts are maximally identified. On 16 December 2011, the Supreme People’s Court issued The Opinions on Exerting the Function of Intellectual Property Rights Judgment to Facilitate Socialist Cultural Development and Prosperity and Promote Independent and Coordinated Economic Development[i], pointing out that “where products acquired in a patented method are not new products, and the patentee can prove that the alleged infringers have manufactured identical products but are unable to prove after reasonable efforts that the alleged infringers have used the patented method, if it may be determined that it is highly likely that the identical products have been produced in the patented method on the basis of specific circumstances of the cases and in light of known facts and common sense, the patentee may no longer be required to provide further evidence in accordance with relevant judicial interpretations on civil evidence; under the circumstances, the alleged infringers shall be required to provide evidence that their methods for producing the products are different from the patented method.”

In accordance with the guideline provided by the Supreme People’s Court, in order to implement the presumption that the accused product has been manufactured through the patented process, the prerequisite is that the plaintiff has to provide evidence showing that the accused defendant manufactures identical products and devote reasonable efforts to providing such evidence, and the key is to show that there is a substantial likelihood that the accused infringer uses the patented process. The defendant shall bear adverse legal consequences should it fail to meet the burden of proof that his manufacturing method is different from the patented method. Then, how shall the plaintiff establish before the court that the defendant is highly likely to have infringed? After going through typical cases, we find out three effective approaches:

  • providing evidence showing that the accused infringer has access to the patented process;
  • presuming the manufacturing process used by the accused infringer by reverse engineering;
  • requesting evidence preservation after devoting reasonable efforts to providing evidence.

The Accused Infringer Has Access to the Patented Process

In a patent infringement dispute where the products manufactured by the patentee and the accused infringer are identical, if the accused infringer has access to the patented process via legitimate or illegitimate ways, it is easy to conclude that the accused infringer probably used the patented process based on common sense. Therefore, the patentee shall present relevant evidence, if any, to the court, and the burden may shift from the patentee to the accused infringer.

For example, in the patent infringement case of Li Chenglin v. Shenzhen Guangming Chuangbo Biological Products Company and Wuhan Guangming Company [ii] tried by Hubei Higher People’s Court, the plaintiff Li Chenglin held a process patent entitled “A Demineralized Human Tooth Matrix and Its Manufacturing Method”. The plaintiff had entered into a patent license agreement with the defendant Shenzhen Guangming Company which was terminated later on due to disputes. The plaintiff found that the defendant Shenzhen Guangming Company continued to manufacture products identical to those manufactured through the patented process after the termination of the license agreement, and another defendant Wuhan Guangming Company sold such products. The court held that according to the circumstances of the particular case, in light of the known facts and common sense, there was a substantial likelihood that the defendant used the patented method, therefore the burden of proof shifted to the defendant to prove that its manufacturing method was different from the patented method. The defendant argued that its manufacturing method was imported from the United States, but failed to provide any substantive evidence thereto and refused to present its original operation records to the court without due cause. Therefore, the defendant was presumed to have infringed the process patent.

Another example is the patent infringement case of Ashland Licensing and Intellectual Property LLC, Beijing Angel Specialty Chemical Technology Co., Ltd. v. Beijing Response-Chem Specialty Chemicals Technology Co., Ltd., Suzhou Ruipu Industry Auxiliary Co., Ltd, and Wei Xingguang et al.[iii], which is one of the Eight Cases of Judicial Protection of Intellectual Property Rights published by Supreme People’s Court in 2013. The plaintiff Ashland Company is the patentee of the invention patent entitled “Method for the Production of Water-In-Water Polymer Dispersions”. Angel Company was the licensee of said patent in China. One of the defendants, Wei Xingguang, who had served as an executive at the plaintiff Angel Company, later left to join the defendant Response-Chem Company as a shareholder and director, and after the establishment of another defendant, Ruipu Company, served as a director thereof. Response-Chem Company and Ruipu Company manufactured and sold aqueous polymer concentrates that were identical to those produced in the patented method.

The plaintiff failed to purchase the accused products from the market since it was an industrial chemical targeting specific customers. The plaintiff also failed to provide evidences that could prove the defendant’s entire process although they tried various means including requesting evidence preservation and notarization. It was noted that Wei and other technical personnel of Ruipu Company used to work for Angel Company and had access to the patented method. The court held that there was a substantial likelihood that the defendant used the patented method in light of the known facts and common sense. Therefore, the burden of proof was reversed to the accused infringer. Ruipu Company claimed that its production process was different from the patented method, but refused to provide corresponding evidence to support its claim. Therefore, the court presumed that the defendant used the patented method.

Presuming the Manufacturing Process by Reverse Engineering

Product analysis is commonly seen in product patent infringement cases and directs to evidence proving infringement. In disputes over process patent infringement, product analysis is also critical. The plaintiff can prove that the accused infringer manufactures identical products by dissecting the accused product. The analysis result may also shed light on the process of the accused infringer. It is possible to presume the process of the defendant by analyzing characteristic traces left by the steps and materials used during production, thus indirectly proving the substantial likelihood of the accused infringer’s infringement.

A typical example of presuming manufacturing process by analyzing components in the final products is the case of BASF v. Nantong Shizhuang Chemical Engineering Company[iv]. BASF is the patentee of the invention patent for “Preparation of Substantially Dust-Free Tetrahydro-3, 5-Dimethyl-1, 3, 5-Thiadiazine-2-Thione Granules”. In this case, BASF presented its internal analysis report of the accused product to the court, showing that the product contained three specific byproducts. BASF also commissioned the testing center of Shanghai Institute of Pesticides to analyze the accused product, and the report of Shanghai Institute of Pesticides was consistent with BASF’s internal analysis report. BASF alleged that the three specific byproducts were the characteristic features of using the patented method, which prove the defendant has used the patented method. The defendant defended that it did not use the patented method, but failed to prove that the three specific byproducts could be derived from other methods. Therefore, the defendant was presumed to have infringed the patent.

Another typical case is the patent infringement case of “Ancient Architecture Color Painting”[v], which is one of the Top 10 Innovative Cases of Intellectual Property Judicial Protection published by Beijing Higher People’s Court in 2017. The plaintiff, named Zhao Liangxin, holds the patent of “Manufacturing Method of Ancient Architecture Color Painting”. During his trip to Chengde, Hebei in December 2013, the plaintiff found that the ceilings of Anyuan Temple painted by the defendant Chinese Academy of Cultural Heritage used the patented method. The patented method employs a technology called screen printing, while the defendant claimed that the ceiling of Anyuan Temple was hand-painted. The plaintiff requested the court for judicial appraisal to determine whether the ceiling was painted by hand or by screen printing. The appraisal report studied the characteristic features of the ceilings of Anyuan Temple and concluded that the ceiling of Anyuan Temple was painted with a method identical to the patented method. Therefore, the court held that “although Zhao Liangxin did not provide evidence to prove that the steps taken by the Chinese Academy of Cultural Heritage to produce the ceiling of Anyuan Temple were identical to those of Claim 1 of the patent, the patentee has already devoted reasonable efforts to providing evidence within his ability. It is proved that there is a substantial likelihood that the Chinese Academy of Cultural Heritage used the method identical to the patented method when painting the ceilings of Anyuan Temple. At this time, the burden of proof shall be reversed to the Chinese Academy of Cultural Heritage, which shall prove that its method was different from the patented method of Zhao Liangxin.” The defendant failed to present substantive evidence to prove its claim of hand-painting, therefore was presumed to have used the method protected by the patent.

Requesting Evidence Preservation after Reasonable Efforts to Provide Evidence

Evidence preservation is a powerful legal weapon which allows the patentee to provide evidence via the power of the court. Where the subject matter of the patent in dispute relates to a process for manufacturing an existing product, patentees may request evidence preservation and thereby obtain the manufacturing processes of the accused infringer. While in practice, sometimes the patentee hesitates to request preservation, fearing that the preservation may not work due to the court’s lack of incentives or the opponent’s refusal to cooperate. In fact, nowadays judges tend to grant requests for evidence preservation with due cause after taking serious consideration. Furthermore, any uncooperative behavior of the defendant may not only fail to conceal evidence, but also cause the judge to believe that there is a substantial likelihood that the defendant did infringe.

A representative of such cases is the retrial case of patent infringement dispute between Weifang Henglian Pulp & Paper Co., Ltd., Yibin Changyi Pucheng Co., Ltd. and Chengdu Xinruixin Plastics Co., Ltd before the Supreme People’s Court[vi]. Yibin Changyi holds a patent directed to a process for manufacturing a modified wood pulp and sued the defendant Weifang Henglian for using its patented method, and the defendant Chengdu Xinruixin for selling the products manufactured in the patented method. Yibin Changyi proved that the defendant’s product was identical to the product obtained in the patented method, and devoted reasonable efforts to providing evidence. Yibin Changyi presented video footages showing the plant, the machinery, and the raw material delivery process of the defendant. In the meantime, the plaintiff requested the court for evidence preservation, which was granted by the court. The court visited the plant of the defendant twice to collect evidence of its manufacturing process; but all the efforts were in vain because the defendant refused to cooperate. The court held that according to the circumstances of the particular case and in light of common sense, there was a substantial likelihood that the defendant used the patented method, therefore, the defendant shall bear the burden of proof to show that its method was different from the patented method. However, the defendant failed to meet its burden of proof as it refused to present evidence of its manufacturing method without due cause, and therefore was presumed to have infringed the patent.

Conclusion

A particular fact, when its existence is hard to prove or disprove, can be presumed to exist or not exist based on the existence of other relevant facts and be determined by employing logics and common sense. The invocation of a presumption reduces risks of failing to provide proof for patentees and provides a smoother way for them to enforce their legitimate rights, especially when they assert patents of manufacturing processes of known products.

Invoking the presumption is not commonly seen yet. On the one hand, whether a presumption can be established is closely related to specific circumstances of each case; the evidence presented by the plaintiff and the plaintiff’s ability to and attitude towards providing evidence may all affect the inner conviction of a judge. On the other hand, lack of relevant laws and interpretations render patentees unfamiliar to the presumption. It is hoped that more cases involving presumption will be tried and published and the invocation of the presumption will be codified, so as to effectively solve the difficulties patentees face in providing evidence and to encourage patentees to actively enforce their rights and further to demonstrate China’s attitude to and determination in intellectual property protection.