Timing of filing divisional applications in Taiwan
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Timing of filing divisional applications in Taiwan

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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.

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