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Limitations on Claimed Patent Scope from Recited Interaction with External Components
Article 58, Paragraph 4 of the Patent Act dictates “the scope of patent rights shall be determined by the claims, and the specification and drawings may be referred to when construing the claims.” Accordingly, the technical features recited in a claim must, in principle, all be incorporated into the scope of the patent rights, and none may be arbitrarily severed or selectively disregarded. In practice, however, claim content may encompass not only the structure of the product, but also signal transmission or interactive relationships between the product and external environmental components. Whether such recitations should be construed as limiting technical features, or merely incidental descriptions of the product's operating context with no significant limitation imposed thereby, has long been a point of dispute. The question becomes especially acute when a patentee, facing unfavorable infringement comparisons in litigation, contends that such recitations of external components are mere surplusage rather than limiting conditions. Acceptance thereof by the court was addressed by the Intellectual Property and Commercial Court (“IPC Court”) in its 2025 (114) Min-Zhuan-Shang-Zi No. 2 civil judgment, which answered in the negative.
In this case, the appellant was the patentee (the “Patentee”), owner of Taiwan Utility Model Patent No. M611958, entitled “Starter Battery for Electric Vehicles” (the “Patent”). The Patentee alleged that Gogoro compact batteries (Model Nos. GPB-1000S and GPB-1000A, together the “Accused Products 1 and 2”) manufactured and sold by the appellee, Guang-Lun Enterprise (“Guang-Lun”), infringed on their patent rights, and brought suit on such basis. While Claim 1 of the Patent is directed to a “starter battery for electric vehicles,” disclosure thereof recites not only the constituent units of the battery itself, but also the signal transmission and interactive relationship between the battery's internal components and the electric vehicle's ECU control unit and electrical energy storage unit. The Patentee argued that the claim language recites only that the protection unit is “electrically connected” to the rechargeable battery pack, the ECU control unit, and the electrical energy storage unit, and contains no language characterizing such functions as “controlled by the ECU control unit,” with the first-instance court, the Patentee contended, having improperly added such limitation without adequately providing reasons for the same. Guang-Lun countered that, for Accused Product 1, charge/discharge protection is performed autonomously by a protection IC built into the battery, which monitors the voltage of each individual cell and automatically outputs a control signal to cut off the charging circuit once a threshold is reached, a process that requires no control signal to be transmitted to the vehicle and no intervention by the vehicle's system whatsoever. Accused Product 2, Guang-Lun further argued, is not even equipped with a battery protection chip circuit, and therefore cannot in any way be equated with the protection unit of the Patent.
The IPC Court dismissed the Patentee's appeal in the referenced 114 Min-Zhuan-Shang-Zi No. 2 judgment, for reasons summarized as follows.
1. As to claim construction, the court expressly held that a claim's recitation of interaction with external components falls within the scope of the rights defined by the claim, stating “While Claim 1 of the Patent is directed to a starter battery for electric vehicles, its body recites not only the constituent units of the battery, but further recites that the respective component units within the battery bear a signal-transmission and actuation relationship with the ECU control unit and the electrical energy storage unit of the electric vehicle in which the battery is used… Accordingly, the battery's constituent components as recited in Claim 1 of the Patent, together with the control and actuation relationship between those components and the electric vehicle's ECU and electrical energy storage unit, all fall within the scope of the claim, and must likewise be treated as technical features against which the Accused Products are compared in determining infringement.”
2. As to the disclosure in the specification, the court, with reference to the specification of the Patent, found the operating mechanism of the Patent to be “The protection unit of the Patent operates such that protection unit 12 transmits the charge level of rechargeable battery pack 11 to ECU control unit 21 via charge-detection unit 14, and the ECU controls the opening and closing of the protection circuit based on that charge level, thereby controlling the charging and discharging of the rechargeable battery pack.”
3. As to the Patentee's shift in position during litigation to circumvent the foregoing, the court likewise took issue therewith, noting “The Appellant's assertion that ‘the protection unit does not need to be controlled by the electric vehicle's ECU control unit’ is inconsistent with, and contradicts, both the content disclosed in the specification and the Appellant's own submissions and statements made in its earlier briefs and during the preparatory proceedings, and is therefore not credible.”
4. Finally, regarding the infringement comparison, the court confirmed that the charging protection mechanism of Accused Product 1 is determined and executed autonomously by the protection IC inside the battery, requiring no control signal to be transmitted to the vehicle and no intervention by the vehicle's system in controlling charging; Accused Product 2 is not even equipped with a battery protection chip circuit, and therefore objectively cannot correspond to the protection unit of the Patent. Applying the All Elements Rule, the court found that both Accused Products 1 and 2 lack multiple key technical features recited in Claim 1 of the Patent, including being “controlled by an external ECU”, and therefore do not fall within the scope of the Patent. The court accordingly held the appeal to be without merit, affirmed the noted judgment, and dismissed the Patentee's claims for injunctive relief and damages.
This case makes clear that a technical feature recited in a claim, even one describing the interactive relationship between a product and external environmental components, must still be incorporated into the scope of the claim, and that courts will not exclude such a feature from the infringement comparison based merely on the presence of external components. Patentees drafting claims are therefore well advised, where the subject matter to be protected is a single product, to focus the claim language as much as possible on the structural features of the product itself, and avoid unnecessarily incorporation into the claims of the product's interactive relationship with external components, to avoid possible interpretation of such language later as limiting the scope of the claim. At the specification-drafting stage, it is likewise advisable to disclose all possible embodiments (such as both externally-controlled and internally self-controlled configurations), supported by corresponding dependent claims, to avoid a narrowing construction based on a single disclosed embodiment. Litigation counsel should also strive for consistency in construing and presenting technical features throughout the proceedings, avoiding a last-minute change in position that creates internal contradiction and risks having the statement disregarded by the court as inconsistent.