Under local practice, any person who considers a patent, which has been granted and published by the Intellectual Property Office (IPO), substantially the same or easily conceivable by persons in the art with reference to prior art can initiate a cancellation action against the patent by submitting relevant prior art exhibits and a brief stating the reasons. If the IPO decides to revoke the patent right in the cancellation procedure, the patentee can file an administrative appeal with the Ministry of Economic Affairs (MOEA), the authority supervising the IPO; if the MOEA affirms the IPO's decision against the patentee, the patentee can then file an administrative suit requesting the administrative court to review the case. Such administrative cases are generally handled by the administrative panel of the IP Court.

The IP Court's recent judgments show that in addition to the disclosure of prior art exhibits, the court pays more attention to whether prior art exhibits provide any motivation for persons with ordinary skill in the art to combine two or more prior art exhibits if lacking an inventive step is a critical issue in the administrative suit. In the IP Court's judgment no. 103-administrative-patent-suit-85, which was issued on 31 March 2015, the IP Court further voluntarily initiated evidence investigation to review another two prior art exhibits which were not submitted by the cancellation petitioner and then concluded that the feature not disclosed by the prior art exhibits submitted by the cancellation petitioner is common knowledge in the art; the judgment affirms the IPO's decision of revoking the patent.

The IP Court's judgment no. 103-administrative-patent-suit-85 is mainly to establish whether a patent relating to a fire-resistant sheet and the method of manufacturing the same lacks an inventive step. The IPO's opinion given in the cancellation decision is that the combination of the prior art exhibits 3, 4 and 5 are sufficient in negating the inventive step of Claim 1 of the patent at issue. The patentee stressed in the cancellation and appeal procedures that the combination of the individual prior art exhibits fails to provide a reasonable connection between the steps of the process as recited in the claim. The IP Court then noticed that prior art exhibits 3, 4 and 5 fail to disclose four of the steps recited in Claim 1 (i.e., (1) opening blended staple fibers, (2) dispersing on a conveyor belt, (3) reeling and (4) packaging).  The IP Court considered step (1) and step (2) to have been common knowledge in the relevant field long before the patent at issue was filed and thus voluntarily provided two prior art documents, one of which is a China laid-open patent case and the other is the patent no. TW I261636, to substantiate its opinion; the court also asked both parties to review the two documents and provide a response. As to step (3) and step (4) relating to reeling and packing, because the specification of the patent at issue fails to explain what effects these steps achieve in comparison with the prior art, and since the patentee (i.e., the plaintiff) failed to provide evidence supporting the inventive step achieved by these steps, the IP Court did not consider that Claim 1 would have an inventive step because it recites the steps of reeling and packaging.

The plaintiff argued that the court should not voluntarily review prior art exhibits other than those submitted by the cancellation petitioner. However, the court's judgment emphasizes that according to Articles 125 and 133 of the Code of Administrative Suit, an administrative court should voluntarily initiate an evidence investigation proceeding in such a suit if necessary, and that according to Article 8 of the Intellectual Property Adjudication Actmutatis mutandis Paragraph 1 of Article 34 of the same Act, if the court already has professional knowledge in some aspect and has given an opportunity in the procedure for the parties to the suit to respond and debate, such knowledge can serve as the basis of the court's judgment.

In the past, the scope of examination of a cancellation action was limited to the prior art exhibits submitted by the cancellation petition and the issues that the cancellation petitioner requested the IPO to review. In the administrative appeal procedure, the MOEA would not review any argument or evidence not reviewed by the IPO in the cancellation action procedure. However, according to the current Examination Guidelines issued by the IPO in 2013, the IPO can voluntarily review issues and/or exhibits not raised or submitted by a cancellation petitioner if necessary (but such "voluntary review" needs to meet some requirements). It seems that the administrative panel of the IP Court now also tends to take its initiative in probing some exhibits not submitted by a cancellation petitioner to solve the issue disputed by the parties to the administrative suit. With regard to the issue on whether the feature recited in a claim but not disclosed by prior art exhibits was commonly known to persons in the art before the filing date of the patent at issue, the IPO failed to thoroughly investigate it and find the fact in the cancellation action. The court could have expressed its opinion on this matter in the judgment and decided to remand the case (requesting the IPO to investigate this issue and revise the decision according to the court's opinion), but the IP Court apparently tends to solve this issue on its own. It is worth observing whether the IP Court will keep doing so. Further, with regard to said "common knowledge in the art" based on which the inventive step is determined, it remains an issue as to whether it is sufficient to prove the common knowledge by providing another prior art document to cure the insufficiency of the cancellation prior art exhibits or it is not sufficient unless new evidence can further prove that persons with such common knowledge are capable of combining the prior art exhibits to accomplish the claimed invention.