One Case a Day | China: Determination of Functional Features - Supreme People's Court Intellectual Property Final No. 369 (2019) "Automatic Elastic Band Machine" Case

Case Introduction
Late at night, continuing with the daily case study.

Following yesterday's discussion on functional features in the U.S., today we share a Supreme Court second-instance precedent from China that provides a highly applicable method for determining functional features.

Article 8 of the "Interpretation (II) of the Supreme People's Court on Several Issues Concerning the Application of Law in the Trial of Patent Infringement Disputes" (referred to as "Interpretation II") stipulates: A functional feature refers to a technical feature that defines the structure, composition, steps, conditions, or their relationships through the function or effect it plays in the invention, except where a person of ordinary skill in the art can directly and clearly determine the specific implementation method to achieve the above function or effect merely by reading the claims. Compared with the indispensable technical features recorded in the description and drawings for achieving the function or effect mentioned in the preceding paragraph, if the corresponding technical feature of the accused infringing technical solution uses substantially the same means to achieve the same function and produce the same effect, and a person of ordinary skill in the art can conceive of it without creative effort at the time of the alleged infringement, the People's Court shall determine that the corresponding technical feature is identical or equivalent to the functional feature.

It is evident that functional features have a clear disadvantage in patent infringement determination, making their identification a focal point of contention among parties in infringement litigation. Let's delve into today's case—Supreme People's Court Intellectual Property Final No. 369 (2019), the "Automatic Elastic Band Machine" case.

Case Information

• Application Number: 201620180916.4
• Invention Title: An Automatic Elastic Band Machine
• First-Instance Information: (2018) Zhe 02 Min Chu No. 1956
• Second-Instance Information: (2019) Supreme People's Court Intellectual Property Final No. 369
• Decision Date: February 25, 2021

Controversial Focus
The involved patent protects an automatic elastic band machine. The relevant claims include technical features such as a feeding device, a pulling device, a flipping mechanical hand device, a feed guide rail device, and a sewing device. The flipping mechanical hand device is fixedly connected to the feed guide rail device. The pulling device includes a clamping mechanism capable of clamping the elastic band and a sliding mechanism that drives the clamping mechanism to move. The clamping mechanism of the pulling device clamps the end of the elastic band at the outlet of the second feeding driving wheel. With the assistance of the second feeding driving wheel, the sliding mechanism drives the elastic band to move through the first and second clamps. The elastic band is then cut by a cutting mechanism located at the outlet of the second feeding driving wheel. After the first and second clamps hold the cut ends of the elastic band, they rotate around the first and second axes, respectively, to fix the ends of the elastic band on the material support frame. The feed guide rail device drives the elastic band to move under the needle of the sewing device for sewing. The second feeding device is equipped with a feeding channel, the upper end of which has a color mark sensor for color block detection of the elastic band, and the feeding channel is equipped with a knot sensing mechanism.

The controversial focus of this case is whether the "sliding mechanism," "feed guide rail," and "knot sensing mechanism" in the claims are functional features.

Views of the Parties
The accused infringing party argued that the "sliding mechanism," "feed guide rail device," and "knot sensing mechanism" described in Claim 1 of the involved patent are functional technical features, and their scope of protection should be determined in conjunction with the embodiments.

The first-instance court held that regarding the "sliding mechanism," "feed guide rail," and "knot sensing mechanism," although the involved patent provides functional descriptions for them, not all technically described features are functional technical features. According to Article 8 of "Interpretation (II)," technical features for which a person of ordinary skill in the art can directly and clearly determine the specific implementation method to achieve the above function or effect merely by reading the claims do not belong to functional features. Specifically, in this case, the "sliding mechanism" and "feed guide rail" are devices used to drive the clamping mechanism to move horizontally, and the "knot sensing mechanism" is installed on the feeding channel to sense knots in the elastic band. A person skilled in the art can understand how these technologies are implemented and their basic structures, so they are non-functional limitations and should not be classified as functional technical features. Accordingly, there is no need to apply the "embodiment + equivalence" interpretation rule for functional features.

Second-Instance Court
1. According to Article 8 of "Interpretation (II)," functional features refer to technical features described using terms that indicate "what they do" rather than "how they do it." Functional limitations must meet the following requirements:

First, they are defined solely by function without using the structural features necessary to achieve the function.
Second, such "functional limitations" do not have a relatively fixed technical structure known to those skilled in the art.

2. Therefore, the following situations generally should not be recognized as functional features:
(1) Technical terms expressed in functional or effective language that have become commonly known to a person of ordinary skill in the art, or technical features expressed in functional or effective language for which a person of ordinary skill in the art can directly and clearly determine the specific implementation method to achieve the above function or effect merely by reading the claims.
(2) Technical features described using functional or effective language but also described with corresponding structural, compositional, material, step, condition, or other features.

3. Thus, the exception "except where a person of ordinary skill in the art can directly and clearly determine the specific implementation method to achieve the above function or effect merely by reading the claims" has two basic meanings:

(1) At the stage of identifying what technical features are functional features, the internal evidence used to determine the specific implementation method of functional features is limited to the claims themselves and does not include other content of the patent document. This belongs to the issue of determining whether a feature is a functional feature. Only when further interpreting already identified functional features or conducting infringement determination for already identified functional features is it necessary to rely on the specific implementation methods recorded in the description and drawings to interpret the already identified functional features or determine identical/equivalence infringement.

(2) A person skilled in the art can directly and clearly determine the specific implementation method from the claims. That is, only technical content familiar to a person skilled in the art can be directly and clearly determined from the claims. At this point, it is not only feasible but also necessary to rely on external evidence to prove that a person skilled in the art can determine the specific implementation method from the claims.

4. The sources of such specific implementation methods typically include:

First, specific implementation methods that a person skilled in the art can already understand from the functional/effective description, i.e., in the relevant technical field, certain functions/effects may have recognized, conventional implementation methods.

Second, the specific implementation meaning of the terminology of the functional executor itself, i.e., technical terms representing the functional executor have a certain degree of structural meaning/certain specific implementation information, and the structural/step meaning of the technical term is sufficient to achieve the desired function/effect.

Third, the specific implementation method directly described by the limitation on the functional executor, i.e., the functional limitation feature adopts the method of "functional or effective language + corresponding structural, material, step, or other features," and the described structure, material, or steps are sufficient to achieve the desired function/effect.

5. Specifically, in this case, the involved patent belongs to the field of mechanical products. The characteristics of this technical field objectively determine that when drafting claims, the technical solution to be protected can usually be defined according to structure and its positional or connection relationships. Therefore, in the mechanical field, component names containing both "structure" and "function or effect" are common. If such mechanical components include relative positional relationships, motion methods, or certain structures in the claims, they do not belong to the "functional features" stipulated in the aforementioned judicial interpretation.

6. For the "feed guide rail device," although "feed" indicates the function of the device, "guide rail device" already clarifies that its structure is in the form of a guide rail. That is, the feed guide rail device is a guide rail device capable of performing the "feed" function, which is the name of a specific mechanical device indicating structural features and does not belong to the functional features stipulated in the aforementioned judicial interpretation.

7. For the "sliding mechanism," the involved patent explicitly defines its relative positional relationships and motion methods in Claim 1. Specifically, Claim 1 of the involved patent records: The automatic elastic band machine includes a feed guide rail device, and the flipping mechanical hand device is fixedly connected to the feed guide rail device. The pulling device includes a clamping mechanism capable of clamping the elastic band and a sliding mechanism that drives the clamping mechanism to move. The sliding mechanism drives the elastic band to move through the first and second clamps. Therefore, the "sliding mechanism" does not belong to the functional features stipulated in the aforementioned judicial interpretation.

8. For the "knot sensing mechanism," a person skilled in the art can directly and clearly determine the specific implementation method of this structural feature merely by reading the claims. Therefore, it also does not belong to the "functional features" stipulated in the aforementioned judicial interpretation.

9. Moreover, in the technical solution of Claim 1 of the involved patent, the "sliding mechanism," "feed guide rail device," and "knot sensing mechanism" are not defined with specific implementation methods. Based on comparison, the accused infringing product includes all the aforementioned structures. The technical features of the technical solution adopted by the accused infringing product are identical to the technical features of the involved patent claims asserted for protection in this case. Although there are differences between it and the specific implementation methods recorded in the description of the involved patent as claimed by the accused infringing party, the specific implementation methods recorded in the description of the involved patent are further limitations on the aforementioned structural technical features made by other dependent claims of the involved patent. However, the patentee did not assert protection for these dependent claims in this case. Therefore, the relevant claims of the accused infringing party lack factual basis and are not supported by this court.

10. The technical features of the technical solution adopted by the accused infringing product are identical to the technical features of the patent claims asserted for protection by the right holder in this case, falling within the scope of protection of the involved patent right.