Since 2022, Taiwan’s Supreme Court and Supreme Administrative Court have repeatedly vacated and remanded appeal cases concerning a programmable controller patent, in which the Intellectual Property and Commercial Court (the IPC Court) had found the patent to lack inventive step.
The grounds for remand rendered by these highest courts primarily concern the following issues in the review of inventive step:
The importance of determining the level of ordinary skill in the art at the time of the patent application;
The need to properly define the ‘primary prior art reference’;
The distinction under the ‘could/would’ approach between a motivation to try and a motivation to implement, in determining whether a person having ordinary skill in the art would combine prior art to arrive at the claimed invention; and
Whether patent licensing to competitors may serve as evidence of commercial success supporting inventive step.
Recent case law
In response to the most recent remand, at the end of December 2025, the IPC Court rendered a second-remand civil judgment (2024 Min Zhuan Shang Geng Er Zi No. 5) and a second-remand administrative judgment (2025 Xing Zhuan Geng Er Zi No. 1) in this series of cases. The reasoning in both judgments is largely consistent, as the IPC Court synthesised and applied the key points identified by the supreme courts.
First, with respect to the level of ordinary skill in the art at the time of filing, the IPC Court adopted the written submissions and in-court testimony of the defendant’s expert witness as the basis for its subsequent inventive step analysis.
Second, in assessing inventive step in a combination prior art scenario, the IPC Court first identified the primary and secondary references, compared the technical features of the patent-in-suit with those of the primary reference, and determined that the differences were disclosed in the secondary reference.
Third, regarding the motivation to combine, the IPC Court found that the references were from related technical fields and addressed similar problems, functions, or purposes. It further held that a person having ordinary skill in the art could, based on the technical content of the primary reference, program the control device, and thus would have been motivated, under specific conditions, to adopt the technology disclosed in the secondary reference, rather than merely relying on hindsight to suggest a motivation to try combining prior art references. Accordingly, in both of these second-remand judgments, the IPC Court concluded that the patent lacked inventive step.
As to the fourth issue – i.e., whether the patentee’s licensing activities constitute commercial success – the IPC Court, in both the civil and administrative remand proceedings, not only reviewed the contemporaneous licence agreements but also, after formulating questions with the parties, issued inquiries to the licensees of the patent-in-suit. These inquiries focused on the reasons for entering into the licences, including what technical problems existed at the time of the patent application, whether the claimed invention could resolve those problems, and whether the licensing agreements were based on the claimed technical features.
Most of the licensees responded that, due to the passage of time, they were no longer able to recall the relevant circumstances. Although some licensees affirmatively indicated that the patent could resolve the technical problems at the time, it still could not be confirmed whether the licensing decisions were actually based on the technical content of the patent.
In addition, the IPC Court found that the licence agreements themselves did not establish that the licensees had obtained licences based on the claimed technical features. Consequently, the IPC Court determined that the patentee failed to prove a direct nexus between the patent licensing and the technical features of the patent.
Key takeaway
The four key points repeatedly emphasised by the Supreme Court and the Supreme Administrative Court in their decisions have now effectively become a checklist for the IPC Court in its recent review of inventive step. These points merit careful attention by litigants, who should be well prepared to address them in advancing or defending patent validity in litigation.
