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

Managing IP is part of Legal Benchmarking Limited, 1-2 Paris Gardens, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

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.

lin.jpg

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

more from across site and SHARED ros bottom lb

More from across our site

Michelle Lee discusses reaching milestones at the USPTO, AI’s role in legal work, and empowering women in tech and IP law
Executive chair Matt Dixon, who reveals a new associate hire, says the firm wants to offer a realistic pathway to partnership while avoiding the ‘corporate machine’ route
Mayer Brown’s role in cardiovascular technology dispute reflects how firms are pursuing precedent-setting cases to try and guide AI and patent law
Kevin Mack, Via’s new president, emphasises the importance of collaborative licensing structures and shares how AI tools can help create new lines of business
A Tokyo District Court ruling concerning movie spoilers, and a second chance for VLSI against Intel were also among the top talking points
Practitioners believe new AI tools at the USPTO will not replace lawyers or disrupt revenue, but instead expose where a trademark attorney’s value lies
Leighton Cassidy Legal hopes to leverage its founder's international experience and provide clients with a rare chance to receive litigation and prosecution under one umbrella
UKIPO rejects trademark application for 'Cristiano Ronaldo Origins' following opposition by Beck Greener client in a rare case that considered actual use
Partners at both firms have voted in favour of the tie-up, which marks ‘the largest law firm merger in history’
Head of IP, Andrew Brennan, and new partner, France Delord, explain how tech provides an edge in the battle for global brand owners’ business
Gift this article