IP Tribunal upholds infringement finding on hairstyling patent

The IP Tribunal of the Supreme People’s Court has rendered a second-instance and final civil judgment, affirming the Ningbo Intermediate Court’s first-instance judgment that Ningbo Quanli Electric Appliance Co, Ltd infringed an invention patent owned by SEB SA on a rotating brush for hairstyling.


In October 2015, SEB discovered that a rotating brush for hairstyling exhibited by Quanli at the 118th Canton Fair infringed its invention patent.

After collecting and notarising evidence, in April 2018 SEB filed a patent infringement lawsuit in the Ningbo Intermediate Court, accusing Quanli of manufacturing, selling and offering to sell the product in question and thereby infringing its patent.

On 8 April 2019, the first-instance court rendered a civil judgment, finding infringement and ordering cessation of the infringing actions, damages of Rmb300,000 and destruction of the moulds for manufacturing the infringing product.

Quanli’s defence

Quanli appealed to the IP Tribunal, arguing that there was no way to ascertain the exact spatial scope of the wording “close” in the feature “the rod has a cylindrical portion having a first diameter close to that of the handle” of claim 1. As a result, the claim’s scope of protection was unclear, making it impossible to conduct an infringement comparison. Even if a skilled person in the art could determine the specific range of “close”, the accused infringing product did not embody this feature. In addition, Quanli held that the term ‘coupling element’ in claim 1 was a functional limitation and its scope should be limited to the technical features and equivalents that are indispensable for realising the function in the embodiments disclosed in the specification of the subject patent.

Compared to the indispensable features, the corresponding features of the accused product were neither identical features nor equivalents; therefore, the accused product did not fall within the scope of protection of claim 1.

Quanli also cited several precedent judgments issued by the Supreme People’s Court to support its arguments, including the Supreme People’s Court Guiding Case 55, among others.

SEB’s rebuttal

In rebutting Quanli’s first argument, SEB produced internal evidence – including records and drawings in the specification of the subject patent, citing applicable judicial interpretation affirming superiority of internal evidence over external evidence in claim construction – and argued that the wording “close” in claim 1 is clear in the context of this.

With regard to Quanli’s second argument, SEB responded that:

  • the whole technical feature, including the term, is not merely defined by function or effect, and a person skilled in the art could directly and clearly determine the embodiments for realising the function of “coupling” by reading the claim only; and
  • even if the coupling element was deemed a functional limitation, the notch engagement in the specific embodiment of the subject patent is not an indispensable technical feature to achieve this function – the coupling of the accused product (ie, socketing with a hexagonal prism), still fell within the scope of the claim.

SEB also submitted the SPC precedent judgment, (2018) Zui Gao Fa Min Shen (1018) to explain the exception to the functional limitation, as provided in the relevant judicial interpretations.

Finding of the Supreme People’s Court IP Tribunal

The interpretation of claims should be based on the usual understanding by those skilled in the art upon reading the claims and the specification. When the description does not specifically describe a technical term, the interpretation of the claims shall not go beyond the reasonable expectations of those skilled in the art.

In this case, claim 1 of the subject patent describes the rod as having a cylindrical portion with a first diameter close to that of the handle. However, it does not specifically limit the exact value (the difference between the two diameters). However, according to the above-mentioned description, combined with the specification and drawings of the subject patent, those skilled in the art could clearly understand the relationship between the diameter of the cylindrical portion and that of the handle. Therefore, the protection scope of claim 1 of the patent at issue is clear.

Claim 1 recites that the coupling element is mounted on the output shaft of the second motor powering the hairstyling accessory. A person skilled in the art could clearly determine the embodiment of the coupling element by reading claim 1, therefore the term ‘coupling element’ is not a functional feature. The claim does not limit the specific approach as to how the coupling element and the hairstyling accessory interconnect. The notch engagement is only a specific embodiment of the patent at issue. The accused infringing product adopts a hexagonal prism connection rather than the notch-engagement connection, but it still falls within the protection scope of the subject patent.

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