Divisional application practice and the five-year deadline

Practitioners familiar with US and European patent systems often assume that divisional applications remain available throughout much of prosecution. In New Zealand, the interaction between acceptance requirements and the five-year examination deadline can significantly narrow the window for filing a divisional application. This article outlines the key differences between Australian and New Zealand practice and explains how to avoid common filing pitfalls.

Why file a divisional application?

A divisional application splits one application (the parent application) into two or more applications, while keeping the parent application’s filing date.

Common reasons for filing a divisional application include:

• The examiner says that your claims cover more than one invention – a divisional application lets you retain the subject matter you would otherwise need to remove.
• You want claims towards a different invention – to target another commercial embodiment or a competitor’s product.
• You need to keep prosecution alive – if the current application is likely heading towards refusal or time is running out to overcome the examiner’s objections, a divisional application provides a further opportunity to pursue protection for supported subject matter.

For many practitioners, these reasons will be familiar. However, what may not be known is that New Zealand imposes a five-year deadline on filing divisional applications. Understanding this deadline early lets you keep your amendment options open and allows you to use divisional applications in your filing strategy, rather than discovering later that they are no longer an option.

Importantly, examination is not automatic in either Australia or New Zealand and must be requested. Timing of your examination request is an important part of a divisional filing strategy in New Zealand.  

How it works, and how Australia and New Zealand differ

In Australia, you can file a divisional application from a standard patent application up to three months after the date of acceptance of the parent application is published. You can a request to postpone acceptance to ensure the application doesn’t go straight to acceptance if a clear examination report issues. That can provide more time to consider claim strategy. Acceptance will only occur once the postponement request is explicitly withdrawn. The Australian application will lapse if you do not withdraw the postponement request before the acceptance deadline.

New Zealand is stricter. A divisional application must be filed before the parent application is accepted. There is no three-month window after acceptance for filing a divisional application. Acceptance can also be postponed in New Zealand. This is the usual mechanism to provide time to decide whether to file a divisional application. The postponement period runs for up to 12 months from issuance of a first examination report. Unlike Australia, the application will automatically proceed to acceptance when the postponement period expires if the application is in order for acceptance.

The five-year deadline in New Zealand

This is where New Zealand differs significantly from US and European practice and where applicants can easily lose divisional filing opportunities.

Under Regulation 71 of the Patents Regulations 2014, examination must be requested within five years of the filing date of the complete specification. Because a divisional application takes the parent application's filing date, those five years run from the parent application's complete specification filing date or the international filing date for a PCT national phase application.

While this deadline is strictly the deadline to request examination rather than to file, a divisional application that is filed after the five-year deadline cannot be examined. So, in effect, the rule limits the filing of a divisional application to five years from the parent’s complete specification filing date.

As a result, an applicant could request examination of the parent application close to the five-year deadline without realising that the opportunity to file a divisional application is about to pass.

What makes the deadline significant in New Zealand is the typical examination timeframe. The Intellectual Property Office of New Zealand (IPONZ) publishes the expected timeframe from requesting examination to receiving a first report (the following as of 23 July 2026):

Australia is considerably faster, with IP Australia aiming to issue a first report within 12 months, or within eight weeks if examination is expedited.

You can ask IPONZ to examine your application ahead of the queue, either by giving good and substantial reasons in the form of a statutory declaration or affidavit, or through the Patent Prosecution Highway (PPH) if corresponding claims have already been allowed elsewhere. This significantly shortens the examination timeframe. However, there is no set timeframe within which an expedited or PPH application will receive its first examination report.

Practical tips

• Consider your divisional strategy early to ensure you can make a decision before the five-year deadline.
• Request examination on filing in New Zealand to account for examination delays and to ensure any unity objections are identified before the five-year deadline.
• Request postponement of acceptance if a divisional filing is under consideration to keep the parent application pending while the decision is made.
• Keep track of the five-year deadline calculated from the parent application’s complete specification filing date, not from the divisional application’s filing date.
• If the five-year deadline is close, file your divisional application and request examination at the same time as a divisional application that cannot be examined can never be granted.

Conclusion

Divisional applications are useful tools in both Australia and New Zealand, letting you preserve subject matter following a unity objection, pursue claims towards a different commercial embodiment, and keep prosecution alive where a parent application has stalled.

In Australia, the three-month window after acceptance is published gives you time to make that decision. In New Zealand, the five-year deadline means the decision needs to be made considerably earlier, and the typical examination timeframe means that requesting examination on filing is the most reliable way to make an informed divisional application filing decision before the deadline.

Accounting for these differences from the outset can help preserve divisional options and ensure a smoother prosecution strategy across both jurisdictions. Please contact us for case-specific divisional application filing strategy.