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

Cassie Hill, partner at Mishcon de Reya, discusses rebuilding client relationships after maternity leave and the pressures facing women at a pivotal stage of their career
Matthew Asbell discusses why empathy is important in law, being inspired by diverse workplaces and working on the latest, greatest large language model
The new partners add patent trial depth in high-value technology sectors including semiconductors, software, and cloud computing
From seller vetting and proprietary screening technology to brand collaboration and industry partnerships, Temu explains how its intellectual property enforcement programme combats infringement on its marketplace
A handful of US firms have quietly invested in European patent talent. Recent moves by Baker Botts and K&L Gates suggest that trend may be accelerating
Loke Khoon Tan and Stephanie Yip at Dentons explain what brand owners need to know ahead of January 1 2027, when updates to China’s Trade Mark Law come into force
New US bills signal that firms should work with clients to ensure they are complying with potential regulatory requirements
Octavio Espejo of Becerril, Coca & Becerril explains how sweeping patent reforms reshape filing strategies, prosecution, and divisional application practice
The UK Supreme Court’s decision in Tesla v Avanci enhances the UK's attractiveness for global FRAND battles, say lawyers at Simmons & Simmons
PE-backed practices now comprise the majority of ranked firms for patent prosecution in the Netherlands, but competitors are confident about their decision to remain independent
Gift this article