Patent infringement cases apply to the basic elements of ordinary civil infringement cases, that is, the act is illegal and has harmful consequences. There is a causal relationship between the two, and the actor is at fault. At the same time, patent infringement cases also have their own particularity, which is particularly noteworthy when both parties submit their own evidence. Proof and evidence of the plaintiff 1. Proof of right 1. The plaintiff's qualification certificate, including the identity certificate of a natural person, the business license of an enterprise or institution or the registration certificate of an institution. 2. Patent certificate, which proves the ownership status of the patent right when it is authorized. 3. Copy of patent registration. In a sense, the copy of the patent register is more important evidence than the patent certificate, because the patent certificate records the ownership status of the patent when it is authorized. After authorization, the ownership status of the patent may change, such as the transfer of the patent right and the invalidation of the patent. These contents cannot be reflected in the patent certificate, but will be recorded in the copy of the patent register. In litigation, this kind of evidence is often ignored by the parties or agents. 4, patent authorization announcement text, different patent announcement text is also different. Invention or utility model refers to the patent claim, specification, abstract and appended drawings; Announce the pictures or photos authorized by the design and a brief description. The text of patent announcement can clearly reflect the scope of patent protection and has direct probative power to the infringement facts. 5. The annual patent fee receipt can prove that the patent continues to be valid. In fact, if a copy of the above patent register is provided, the evidence can be omitted. Because in the bottom line of the copy of the patent register, it is indicated that "the annual patent fee has been paid to a certain day." In judicial practice, the patentee provides proof of the patent annual fee receipt to show that the patent has paid the annual fee and the patent is still valid. However, in the practice of patent payment in China National Intellectual Property Administration, even if the patent has been declared invalid, or the patent right is terminated due to failure to pay the annual fee, the patent fee can still be paid, so as to obtain a patent annual fee receipt. Therefore, it is not sufficient and sometimes even wrong to prove that the patent continues to be valid through the annual patent fee receipt. In this way, a copy of the aforementioned patent register is extremely important. The author thinks that the reason why the patent annual fee receipt is used to prove the continued validity of the patent in practice may be influenced by Article 4 of the Supreme People's Court's Provisions on Applicable Laws for Stopping Infringement of Patent Right before Litigation, which stipulates that the patentee shall submit documents to prove the authenticity and validity of his patent right, including patent certificate, patent claim, specification and patent annual fee payment voucher. Here, the patent annual fee payment certificate is one of the true and effective certificates of the patent, but there is no mention of the copy of the patent register, which cannot be said to be a defect. 6. The utility model patent search report. Article 8 of the Provisions of the Supreme People's Court on the Applicable Law in the Trial of Patent Disputes stipulates that if the plaintiff files a lawsuit for infringement of the patent right of utility model, he shall issue a search report made by the patent administration department of the State Council at the time of prosecution. Therefore, after the promulgation of the judicial interpretation, many courts refused to accept the patent infringement lawsuit of utility model without providing the search report of utility model. However, this practice obviously does not conform to the provisions of Article 108 of the Civil Procedure Law. Subsequently, the Supreme Court made it clear in its reply to the request of the Beijing Higher People's Court that issuing a search report for utility models is not a condition for bringing a patent infringement lawsuit for utility models. However, if the search report is not provided and the defendant requests invalidation of the patent, and there are no other circumstances that cannot terminate the lawsuit, the people's court shall terminate the lawsuit. Therefore, it is best for the plaintiff to provide a search report of the utility model patent when suing to avoid the case being suspended. 2. Infringement evidence 1, documentary evidence, and general notarization. After the patentee discovers the infringement through market investigation, he will generally apply to the notary office for notarization of the process of purchasing the infringing products and the purchased infringing products, or investigate and notarize the infringing site (such as promising to sell) or the installation place of the infringing products, and obtain a notarization certificate, thus proving the defendant's infringement. In the process of notarization and evidence collection, the patentee had better take the initiative to ask the seller for the product description, business card, purchase invoice or receipt of the seller of the infringing product, so as to further clarify the producer and seller of the product. At the same time, the patentee may ask the notary office to explain the source and authenticity of the above materials and record them in the notarial certificate. In addition, by the way, you should also consider it when choosing a notary office. For example, in provincial capital cities, you can choose provincial notary offices instead of district notary offices. One possibility is that the district notary office lacks experience, and the other possibility is that the district notary office excuses for various reasons out of local protection or fear of retaliation. In addition, when choosing a notary office, we should also pay attention to the provisions of Article 14 of the Rules of Notarization Procedure: Notarization matters shall be accepted by the notary office where the parties have their domicile, habitual residence, behavior or fact occurred. Notarization matters involving real estate shall be accepted by the notary office where the real estate is located. Notarization practice area refers to the geographical scope of notarization institutions accepted by the judicial administrative organs of provinces, autonomous regions and municipalities directly under the Central Government according to the provisions of Article 25 of the Notarization Law and Article 10 of the Measures for the Administration of Notarization Institutions, as well as the planning for the establishment of local notarization institutions. Therefore, when choosing a notary office, we should pay attention to the double restrictions of its jurisdiction and practice area, so as to avoid the rejection of the application or the procedural defects of the notarial certificate due to wrong acceptance. 2. Physical evidence, infringing products purchased by the patentee from the market. The purchased infringing products are sealed and photographed by notaries. Before submitting it to the court, the plaintiff should ensure that the seal is intact, otherwise the defendant can raise an objection during the cross-examination and refuse to admit the infringing product. As mentioned earlier, the process of obtaining material evidence is notarized. The patentee or his agent, together with the notary, goes to the infringer as an ordinary consumer to buy the infringing product, and then seals it up. In the notarial certificate, this process will be explained, but many notarial certificates do not specify the sealed products in detail. For example, the author handled a trademark infringement case. As the agent of the defendant (seller), the author found that the notarial certificate did not mention the model and specification of the infringing product submitted by the plaintiff in court and stamped by the notary office. Although the sealed bag is airtight, there are no figures on it indicating that it is consistent with the notarial certificate. However, the plaintiff has notarized and obtained evidence and litigated a large number of sellers, which cannot absolutely rule out the possibility that the sealed material evidence in this case is not betrayed by the defendant. After cross-examination and debate in court, the judge also agreed with this opinion. Three. Evidence of loss 1. Patent licensing contract. Nowadays, in judicial practice, few plaintiffs provide evidence of direct or indirect losses, mainly because it is difficult and costly to prove such evidence. At present, a large number of patentees sign patent licensing contracts with others and claim compensation according to the agreed licensing fees. Although some patent enterprises will sign nominal patent licensing contracts with business units, they will also handle the filing procedures and payment and tax payment vouchers for the corresponding patent licensing fees, but the licensees have not actually produced patented products. In this case, strictly speaking, the license fee agreed in the contract should not be used as a reference for compensation. In this regard, although the defendant can raise a defense, in view of the strong probative force of the patent licensing contract and the clear provisions of the law, the judge will generally adopt it. 2. Financial audit report. According to the relevant provisions of the Patent Law, the amount of infringement compensation is determined with reference to the aforementioned patent license fee, as well as the losses suffered by the obligee or the interests gained by the infringer due to infringement and the legal compensation amount. When the plaintiff claims that the amount of compensation should be based on the losses it has suffered, it shall provide a financial audit report on the profitability of its products, and take the product of the total sales reduction caused by the defendant's infringement or the number of infringing products manufactured by the defendant as the basis of the plaintiff's loss amount; When the plaintiff advocates taking the defendant's profits as the basis for compensation, the plaintiff usually applies to the court to preserve the defendant's financial accounting books, and after being audited by an independent third party, the defendant's infringing profits are determined by the audit conclusion, so as to clarify the basis for compensation for the defendant. Finally, in the statutory compensation, the plaintiff can provide some auxiliary evidence to prove the defendant's infringement plot and the market value of the patented product, which can be used as a reference factor for the court to determine the specific compensation amount, such as the relevant contract signed by the defendant and the third party, the price of the infringing product on the defendant's website and other publicity materials. The defendant's cross-examination and proof After receiving the notice of responding to patent infringement litigation, the defendant should not blindly negotiate with the plaintiff for settlement, but should comprehensively analyze the evidence provided by the plaintiff and collect evidence that is beneficial to him according to the defense claim. In practice, the defendant has a variety of defense claims, and the defendant has the following different defense claims against the above plaintiff's claims. First, the defense of the right defect When the defendant puts forward the defense of the right, it usually defends the plaintiff's subject qualification, the ownership of the patent right and the effectiveness of the patent right. Patent infringement litigation is usually initiated by the patentee himself, but in some cases, the licensee brings a lawsuit. In this case, the defendant should first review the licensing method. According to the provisions of judicial interpretation, only the licensee of exclusive license can bring a lawsuit as a plaintiff, while the licensee of general license and exclusive license cannot bring a lawsuit as a plaintiff without the permission of the patentee, which involves the question of whether the plaintiff has the qualification of litigation subject. Some original patentees still file infringement lawsuits in the name of the patentee after the patent right has been transferred to others, which is obviously not in line with the law. The defendant can provide a copy of the patent register to prove that the patent right has been transferred, and the plaintiff does not have the qualification of litigation subject, and requests the court to reject his claim. Another situation is that the patent right may have been terminated, but the plaintiff filed an infringement lawsuit against the defendant for the sake of competitive strategy. In this case, it is also very necessary for the defendant to provide a copy of the patent register. According to the detailed rules for the implementation of the Patent Law, anyone can apply to China National Intellectual Property Administration for a copy of the patent register. Therefore, as long as the necessary fees are paid, there are no legal or practical obstacles for the defendant to provide a copy of the patent register. A special case is that the patentee brings a lawsuit against the manufacturer or seller who manufactured or sold the same product during the period from the date of patent application to the date of patent announcement authorization. According to the law, the manufacturing or selling behavior during this period does not constitute patent infringement, so the defendant can also defend as a seller or manufacturer. Second, the basic principle of non-infringement defense infringement judgment is the principle of universal application. If the defendant defends against infringement, it shall prove that the infringing product lacks the necessary technical features in the claim, or that the technical features of the infringing product are substantially different from those in the patent claim, which does not constitute equivalence. In this regard, the defendant can only draw a conclusion by comparing the patent claim provided by the plaintiff with the infringing product, and can also apply for identification if necessary. But if the defendant claims no infringement, the reason is that the product was produced by others as the defendant. In this case, how should the court allocate the burden of proof? Does the plaintiff prove that the product is indeed produced by the defendant, or does the defendant prove that the product is not produced by itself? The author thinks that the burden of proof should be borne by the plaintiff. First of all, proving that the defendant's infringement is the core element of the plaintiff's lawsuit. In addition, as far as the principle of proof is concerned, it is easier to prove action than inaction. The third situation is that the defendant advocates the principle of estoppel without infringement. In order to prove the plaintiff's estoppel, the defendant should prove that the plaintiff made some restrictive interpretations of his patent claim or specification in the process of patent application or invalidation, or in the national intellectual property certificate or the opinion statement made by the Patent Reexamination Board or other patent-related documents. However, in the patent infringement litigation, the plaintiff advocates applying the principle of equivalence to determine the defendant's infringement, which expands the scope of patent protection. This is not good for the defendant and the public, nor does it conform to the principle of good faith, so it is not allowed for the patent office. To this end, the defendant should know all the patent documents in detail. Like the above-mentioned copy of the patent register, anyone can apply to China National Intellectual Property Administration for copying patent documents. Therefore, after receiving the complaint from the defendant, the patent defendant should first apply to China National Intellectual Property Administration for copying the patent documents involved. Three. Defense of known technology (design) The so-called known technology (design) refers to the technology (design) that was published in domestic and foreign publications, used publicly in China or known to the public in other ways before the filing date of the invention, utility model or design patent. To this end, the defendant shall provide publications that are the same as or equivalent to the technical scheme adopted by the infringing products, or products with exact sources, sales or use time, and relevant supporting documents, such as product manuals, product atlas, sales invoices, witness testimony, etc. Some defendants, after learning that they were accused of patent infringement, the first thing they did was to find the above evidence to prove that the plaintiff's patent right was not novel and declare it invalid. This point is mainly used in the litigation of design patent infringement, because the application for design patent is relatively easy, and the patent office does not conduct substantive examination after accepting it, which makes the "effective" patent have the risk of "invalid". Fourth, the defense of the right of first use Although the right of first use will not lead to the invalidation of the plaintiff's patent right, it is a clear defense that does not constitute infringement. In practice, many defendants will choose to use the preemptive right to defend, but few of them succeed, mainly because of insufficient evidence. Usually, the defendant should provide the following evidence: 1, design drawings and process documents before the plaintiff's patent application date; 2. Information on the quantity and production capacity of the equipment purchased by the plaintiff before the patent application date. V. Contract defense There is such a case: the patentee signed an exclusive license contract with others. But soon after the contract was signed, the patentee signed a license contract with another person. Being kept in the dark, the exclusive licensee later found that the products of the general licensee entered the market, so he filed an infringement lawsuit against the general licensee. At this time, the general license licensee took out the contract defense, and the plaintiff had no choice but to withdraw the lawsuit and file a breach of contract lawsuit with the patentee. This case is a typical successful case of contract defense. In another case, the defendant obtained the license of the same or equivalent technical scheme as the plaintiff's patent from others. In this case, the defendant should provide the court with a license contract. Although the evidence can't exempt the defendant from tort liability, the defendant can apply for an additional assignor as the defendant, and the assignor and * * * shall be liable for compensation to avoid directly assuming all tort liabilities. This is also a litigation skill. When it is inevitable to bear the responsibility, try to bear as little as possible, that is, part of the exemption. The intransitive verb argues that the infringement profit is lower than the amount of compensation demanded by the plaintiff. When bringing an infringement lawsuit, the plaintiff usually takes the patent license fee as the basis of the amount of infringement compensation, or the legal compensation limit of 500 thousand yuan as the basis of compensation. The latter, because of the law, many plaintiffs simply file a lawsuit directly according to the upper limit of 500,000 yuan. If the defendant's infringement is established, but the profit is obviously lower than the plaintiff's claim, the defendant can defend the plaintiff's excessive compensation with the amount of his own infringement profit. Therefore, the defendant should provide a credible financial audit report to prove its profitability. At the same time, you can also provide other supporting evidence, such as the company's business license, which proves that the time interval between the establishment date and the infringement is short, so as to further reduce your liability for compensation. Seven. According to the second paragraph of Article 63 of the Patent Law, anyone who uses or sells a patented product that he doesn't know was manufactured or sold without the permission of the patentee, or a product directly obtained according to the patented method for the purpose of production and operation, shall not be liable for compensation. Therefore, this article provides a good legal basis for the defendant, who should make full use of it. To this end, the defendant should provide accurate evidence from legal sources, such as sales contracts, lease contracts, invoices, transport documents and all other evidence to prove that the transaction is legally established. At the same time, the defendant can provide other relevant evidence, such as sealed samples and product pictures. In order to avoid the defendant's objection to the relevance of the above evidence. Of course, this is aimed at a more formal defendant company. In practice, some self-employed individuals are usually unable to provide the above detailed evidence due to management problems, and will face the adverse consequences of being liable for compensation because they cannot provide legal sources.