Taiwan: IP office issues update on unity-of-invention requirement

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Taiwan: IP office issues update on unity-of-invention requirement

According to Article 33 of the Patent Law, invention patent applications should be filed on a case-by-case basis. Where two or more inventions are so linked that they form a single general inventive concept, they may be claimed in a single application. In other words, a single application can cover two or more inventions only when the claimed inventions are in possession of a common feature which is novel or non-obvious over the prior art.

As there are some grey areas in the criteria for determining whether an invention patent application meets the unity-of-invention requirement set out in Article 33 of the Patent Law, recently, Taiwan's IP office, after seeking opinions from practitioners, has introduced amendments to the new criteria implemented from January 1 2019. The following are the main amendments meriting the applicant's attention:

1) An examiner should have completed examination of a set of claims as to novelty and inventive step of the claimed invention when he/she raises the unity-of-invention issue. In other words, it is not permissible for an examiner to issue an official letter/office action merely based on the unity-of-invention issue. In principle, the examiner should choose Claim 1 and its dependent claims as the basis for preliminary examination.

2) If an applicant fails to overcome the lack-of-unity rejection after filing an amendment or argument against an official letter in which the examiner has raised not only the novelty and/or inventive step issue but also the unity-of-invention issue, the examiner may formally reject the application. At that time, it is a must for the applicant who wishes to further prosecute the application to file a request for re-examination.

3) If an examiner has rejected all the claims for being devoid of novelty or inventive step, he/she cannot raise a lack-of-unity rejection afterwards. The underlying rationale is that the applicant should be given full opportunity to file amendments or arguments in an unfavourable situation.

In view of the above amendments, the applicant is advised to: (1) define the most essential feature of an invention in Claim 1 and its dependent claims; (2) file a set of revised claims to meet the examiner's requirement, if acceptable, and to, in turn, obviate the unity-of-invention rejection; and (3) pay special attention to the respective deadlines for filing divisional applications at different stages and file divisional applications at appropriate times.

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Chiu-ling Lin


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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