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

Tatiana Campello reflects on 30 years of practising at the firm, and urges women IP attorneys to think beyond the day-to-day
A David v Goliath battle involving TikTok, and Via Licensing Alliance adding new members to its Voice Codec patent pool, were also among the top talking points
Latham & Watkins bolstered its IP litigation bench in California with the addition of Kieran Kieckhefer, as partner demand for trial-ready expertise shows no sign of slowing
With the launch of a new patent eligibility AI tool, Sterne Kessler is leading a growing movement of law firms taking AI development into their own hands
UPC cases are (very) gradually becoming more distributed across other local divisions outside Germany, which can only be good news for the pan-European forum
Clarification concerning jurisdictional reach and latest stats released by the court were also among the top talking points in recent weeks
Although unanimous decision by the top court clarifies several aspects of the honest concurrent use defence, practitioners say ambiguities remain
Tristan Sherliker says he hopes to solve an access to justice issue by making the automated court bundle tool free to use
The team, comprising two partners and one senior consultant, plans to offer “highly differentiated” services to clients
HGF’s new ownership model frees it from the hiring constraints of traditional partnerships, its CEO told Managing IP
Gift this article