In a judgment concerning a dispute over infringement of an invention patent, the Supreme People's Court held that the scope of protection of a patent claim shall be determined by the content of the claim. Where a numerical range feature is defined in the claim, if the corresponding numerical value of the alleged infringing product consistently falls within that range and essentially achieves the same technical effect as the patented invention, the alleged infringer's defense that the product is subject to manufacturing tolerances, and that such tolerances do not necessarily affect the numerical range feature defined in the claim, is generally not supported.
This article concerns a dispute over infringement of an invention patent, with the case summarized as follows:
The patentee of the involved invention patent (hereinafter referred to as "the patent") is Company A, which granted Company B a non-exclusive license to use, sell, offer to sell, and import any product protected by the patent in China. Companies A and B filed a lawsuit with the first-instance court, alleging that Companies C and D had manufactured, sold, and offered to sell staple cartridge products infringing the patent without authorization.
The first-instance court issued a civil judgment dismissing the claims of Companies A and B. The court held that the main issue in dispute was whether the alleged infringing technical solution fell within the scope of protection of the patent. The phrase "staples formed at different formed heights" as defined in Claim 1 of the patent was interpreted to include numerical limitations. In the embodiments of the patent, the difference in formed height between staples of different tip lengths exceeded 0.25 mm. The background art, embodiments of the patent, and related products in the same industry all imposed corresponding limitations on the difference in formed height between inner and outer staples to achieve the clamping effect of providing a transition from a tightly compressed hemostatic portion to a non-compressed adjacent portion of tissue. The height difference of the staples in the alleged infringing product ranged between 0.008 mm and 0.121 mm, which was deemed reasonable due to manufacturing and usage tolerances. Furthermore, this height difference was significantly smaller than the values specified in the background art, embodiments of the patent, and related industry products for achieving the beneficial effects of the patent, making it difficult to achieve the intended advantages. Therefore, the technical solution adopted by the alleged infringing product was neither identical nor equivalent to the feature "forming the plurality of staples to have different formed heights" in Claim 1 of the patent and did not fall within the scope of protection of the patent.
Companies A and B was dissatisfied and appealed the decision.
The Supreme People's Court issued a civil judgment overturning the first-instance ruling. It ordered Companies C and D to cease the infringement, with Company C to compensate Companies A and B for economic losses amounting to RMB 2 million, and Company D to bear joint and several liability for RMB 120,000 of this amount. Companies C and D were also ordered to pay Companies A and B RMB 300,000 in reasonable expenses incurred to enforce their rights.
In its final and effective judgment, the Supreme People's Court held that the issues in dispute at the second-instance trial were whether the alleged infringing technical solution fell within the scope of protection of the amended Claim 1 of the patent and the determination of liability for infringement.
The scope of protection of a claim shall be determined by its content, and the interpretation of the claim must align with the inventive purpose of the patent. A person skilled in the art, upon reading the claims and the specification, would understand that the patent aims to achieve, through the cooperation of the staple cartridge and the anvil portion, the formation of staples with different formed heights from identical staples, thereby achieving the clamping effect of tightly compressed inner staples for hemostasis and non-compressed outer staples for clamping. Claim 1 of the patent does not specifically define the numerical difference in the formed heights of the staples. The first-instance court’s finding that the phrase "staples having different formed heights" in Claim 1 includes a numerical limitation was erroneous.
Regarding whether the alleged infringing product possesses the disputed technical feature of "the cooperation of the staple cartridge and the anvil portion causes a plurality of identical staples to be formed with different formed heights", measurement data showed that the groove depths on both sides of the anvil of the 2020 product were configured higher on the outer side and lower on the inner side. Specifically, the difference between the outer and middle groove depths exceeded 0.35 mm, with measured differences ranging from 0.359 mm to 0.375 mm. Offsetting this against the height difference of 0.3 mm in the outer-high, inner-low configuration of the staple cartridge resulted in a difference of 0.059 mm to 0.075 mm.
Based on the tolerance value of 0.05 mm confirmed by Companies A and B, the effective design difference ranged from 0.009 mm to 0.025 mm. Although Companies C and D argued that the design difference in groove depth between the inner and outer sides of their anvil was 0.3 mm, with a tolerance of ±0.1 mm, and that the measured differences of 0.359–0.375 mm fell within this tolerance range, they could not provide valid evidence to support this claim. Moreover, the effective design differences asserted by Companies A and B consistently exceeded 0.35 mm, with no instances below this value. Therefore, there was no sufficient basis to attribute the portion stably exceeding the baseline to tolerance.
Accordingly, it could be confirmed that, based on this design difference, when the alleged infringing staple cartridge was used with the 2020 product, the formed height of the outer staples consistently and stably exceeded that of the middle staples, thereby achieving the clamping effect of providing a transition from a tightly compressed hemostatic portion to a non-compressed adjacent portion of tissue. The 2020 product of Company C, when used with the alleged infringing staple cartridge, exhibited a design difference in staple formed height, enabling the formation of different formed heights from identical staples. In light of the undisputed technical comparisons presented by both parties, the technical solution used in the alleged infringing product fell within the scope of protection of Claim 1 of the patent.
Through this judgment, the Supreme People's Court clarified the evidentiary threshold for the "tolerance defense," providing an operable framework for similar future cases. On one hand, it prevents infringers from evading patent protection under the guise of "tolerances"; on the other hand, it encourages patentees to define numerical ranges and tolerance boundaries more clearly when drafting claims. This ruling holds guiding significance for patent infringement determinations in the field of precision medical devices in China.
(2022) Zui Gao Fa Zhi Min Zhong No. 214
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