Taiwan: Claim amendment during a patent suit

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Taiwan: Claim amendment during a patent suit

A defendant in a patent lawsuit filed before the IP Court may, as a defence, challenge the validity of the patent in suit, and file a separate invalidation action against the patent with the IP Office. Although the IP Court and the IP Office often agree on patent validity in their decisions, there are sometimes disparities.

In a judgment issued in August 2015 in a patent infringement lawsuit, the Supreme Court expressed concern over the different stances adopted by the IP Court and the IP Office toward post-grant claim amendment.

The patent in suit is directed to a method for improving transmission of video data. However, in claim 1 of the patent, the preamble is followed by the expression "characterized in that" rather than "comprising the steps of" or the like. The defendant therefore argued that the patent in suit should be cancelled in view of the indefiniteness of the scope of claim 1 before the court and filed an invalidation action against the patent in suit. The patentee then filed a petition for post-grant claim amendment with the IP Office to replace "characterized in that" in claim 1 by "comprising the following steps".

According to the Examining Guidelines, the IP Office, if prepared to admit a post-grant amendment, should serve a copy of the amended claims on the invalidation petitioner for it to submit any observation thereon.

In this invalidation action, the amendment was indeed served on the invalidation petitioner, namely the defendant. The relevant documents were also entered into the IP Court's docket. In general, the IP Court would take this to mean that the IP Office is prepared to admit the amendment. However, in the infringement lawsuit, the IP Court opined that the claim amendment should not be admitted because claim 1 as amended was still indefinite. The patent was thus deemed invalid by the IP Court.

It was after the patentee filed an appeal with the Supreme Court that the IP Office formally allowed the post-grant amendment. However, the IP Office found that the claims did not involve an inventive step and cancelled the patent.

Noting the disparity between the IP Court and the IP Office regarding the admissibility of the claim amendment, the Supreme Court, in response to the appeal filed by the patentee against the judgment rendered by the IP Court, remanded the case to the IP Court for reconsideration, commenting that since the IP Office had served a copy of the claim amendment on the invalidation petitioner (the defendant), the IP Court's determination that the amendment was inadmissible was questionable.

This case sheds light on the need to review the claims of a patent and file any post-grant amendment, if necessary, when considering filing an infringement lawsuit in Taiwan based on the patent and to file the lawsuit after the amendment is granted.

Tung-Yang-Chang-Tony

Tony TY Chang


Saint Island International Patent & Law Offices7th Floor, No. 248, Section 3Nanking East RoadTaipei 105-45, Taiwan, ROCTel: +886 2 2775 1823Fax: +886 2 2731 6377siiplo@mail.saint-island.com.twwww.saint-island.com.tw

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