Timing of filing divisional applications in Taiwan

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

Timing of filing divisional applications in Taiwan

Sponsored by

saint-island-400px.png
taiwan-4743542.jpg

Fiona Yin of Saint Island International Patent & Law Offices provides a guide to the considerations for patent applicants in deciding when to submit a divisional application

In the patent filing process, applicants may need to file divisional applications to address unity of invention concerns raised or expedite the securing of protection for allowable claims. Therefore, it is essential for applicants to understand when to file a divisional application and what to be aware of during the process.

Taiwan's patent system adopts a relatively lenient attitude towards the filing of divisional applications for inventions. In other words, so long as the parent application is pending or is within three months of receiving a notice of allowance, whether it is an originally filed application or an application that has already been divided, it can serve as the basis for filing a divisional or sub-divisional application, taking advantage of the priority or filing date of the parent application. However, a divisional application can no longer be filed for cases that have received a final office action, since the examination process has been completed.

Furthermore, according to the Patent Act, a divisional application cannot go beyond the description or drawings of the parent application and what is claimed should not be identical to the inventions called for in the approved claims of the parent application.

If a divisional application is filed during the pendency of the parent application, the examination of the divisional application continues from the procedure left unfinished in the parent application. To be more specific:

  • If a divisional application is filed during the preliminary examination stage of the parent application, the examination of the divisional application will start from the preliminary examination stage; and

  • If the divisional application is filed when the parent application has already entered the re-examination stage, the divisional application will directly enter the re-examination stage.

The difference between starting the examination of a divisional application from the preliminary examination stage and starting from the re-examination stage mainly lies in the number of opportunities for the applicant to respond to the rejection by the Taiwan Intellectual Property Office. If a divisional application is filed during the preliminary examination stage, the applicant will have at least three opportunities to file arguments or amendments; namely against:

  • The first examination opinion pre-notification in the form of an official letter;

  • The first formal office action; and

  • The re-examination opinion pre-notification (an official letter).

On the other hand, if a divisional application is filed during the re-examination stage, the applicant may only have one opportunity to respond; specifically, to the re-examination opinion pre-notification. If the rejection cannot be overcome, the applicant will receive a final office action. In that case, there will be no further opportunities for division.

The following diagram illustrates the different stages of a divisional application in Taiwan which enters the preliminary examination or the re-examination stage, depending on the timing of filing the divisional application. This information is provided to help applicants to decide the most appropriate time to file divisional applications so as to better plan their patent filing strategies.

Saint Island graphic.svg
more from across site and SHARED ros bottom lb

More from across our site

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
Anton Hopen, shareholder at Trenam Law, shares how counsel should construct Section 101 claims as early 2026 PTAB data shows reversals rising in technical cases
Gift this article