This case is a real second‑instance civil judgment issued by the Supreme People’s Court Intellectual Property Tribunal of China. All corporate names are anonymized. The plaintiff, Bright Equipment Co., Ltd, held a valid Chinese utility‑model patent for a household humidifier structural improvement. The defendant, Ocean Hardware Manufacturing Co., Ltd, produced and sold competing humidifier products. The core legal controversy focuses on prior‑art defence under Article 67 of the Chinese Patent Law, the comparison rules for prior‑art defence, and judicial standards for “no substantial difference” between technical features国家知识产....
Bright Equipment obtained the utility‑model patent for an anti‑gravity humidifier in June 2021. The patent claims described a unique internal water‑guide structure, which prevented water leakage during tilting. The company invested in mass production and market promotion and obtained stable market sales. Later, Bright Equipment purchased humidifier products manufactured by Ocean Hardware through notarized shopping, and found that the competing product contained almost all technical features recorded in the patent claims. Bright Equipment filed a patent‑infringement lawsuit in an intermediate intellectual‑property court. The plaintiff requested the court to order the defendant to cease manufacturing and sales, destroy inventory products, and compensate economic losses and reasonable litigation expenses.
In the first‑instance proceeding, Ocean Hardware did not deny that its product fell within the protective scope of the plaintiff’s utility‑model patent. However, the defendant raised a statutory prior‑art defence. The defendant submitted product design drawings, internal technical documents and third‑party processing contracts, proving that this set of humidifier structural solutions had been completed and disclosed to cooperative suppliers in July 2020, well before the patent filing date in June 2021. Ocean Hardware argued that the technical solution it implemented belonged to prior‑art publicly known before the patent filing date, and therefore its product should not constitute patent infringement under the Patent Law of China中华人民共....
Bright Equipment counter‑argued that the prior‑art evidence submitted by the defendant was internal enterprise drawings, which had not been publicly released to the whole society. According to the definition under Chinese patent law, prior‑art refers to technologies known to the public at home and abroad before the filing date. Internal design documents that had not been publicly disseminated could not qualify as valid prior‑art evidence. The plaintiff requested the court to reject the defendant’s defence and support all its claims for relief.
The first‑instance court held that the defendant’s design drawings were only circulated among several cooperative suppliers, and there was no open sale, publication or public demonstration. The drawings had not been made available to the general public. Therefore, the submitted materials could not constitute legally‑recognized prior‑art. The court ruled that Ocean Hardware constituted patent infringement and ordered the defendant to stop infringement and pay compensation for economic losses. Dissatisfied with the first‑instance judgment, Ocean Hardware filed an appeal to the Supreme People’s Court Intellectual Property Tribunal.
During the second‑instance trial, the appellant supplemented new evidence, including sample delivery records, social‑media release screenshots and product pre‑order records. These new pieces of evidence jointly proved that the humidifier structure recorded in the drawings had already been displayed and disclosed to potential buyers in public industry channels in July 2020. The appellate court conducted a technical comparison strictly following judicial interpretation rules.
The Supreme People’s Court clarified three key judicial rules for prior‑art defence. First, prior‑art must be publicly accessible to the public before the patent filing date. Confidential internal enterprise documents cannot become prior‑art; partial disclosure to limited business partners does not equal public disclosure. Only when technical information is no longer restricted and can be obtained by relevant persons in the industry can it be recognized as prior‑art国家知识产.... Second, prior‑art defence adopts a single‑document comparison rule. Courts compare the accused infringing technical solution with one complete prior‑art technical solution, instead of combining multiple scattered prior‑art documents to piece together a new technical solution. It is improper to mix different technical features from multiple reference documents to build a contrast baseline. Third, the standard for establishing prior‑art defence is: all technical features of the accused product falling within the patent scope are identical or have no substantial difference compared with corresponding features of one prior‑art solution. Conventional direct replacement of well‑known means in the same field belongs to “no substantial difference” and satisfies the defence condition最高人民法....
After comparing technical features one‑by‑one, the appellate court confirmed that all core structural features of the accused humidifier product were fully disclosed in the prior‑art solution publicly disclosed in July 2020. Individual minor structural adjustments were only conventional equivalent replacement of known technical means and produced no new technical effect. Therefore, the prior‑art defence of Ocean Hardware was legally established. The Supreme People’s Court reversed the first‑instance judgment and dismissed all litigation claims submitted by Bright Equipment.
This judgment delivers important practical guidance for Chinese domestic manufacturing enterprises. Enterprises sued for patent infringement should actively evaluate the possibility of prior‑art defence. It is worth noting that prior‑art defence does not require filing a separate patent‑invalidity petition. Courts may directly apply this defence in infringement proceedings, which greatly improves litigation efficiency. However, defendants must provide sufficient and complete public‑disclosure evidence. Simple internal drawings without public‑disclosure traces usually cannot support this defence. For patent applicants, before filing new utility‑model or invention patent applications, thorough prior‑art retrieval should be performed to avoid applying for patents based on existing public technical solutions.
