Since commencement of the Raising the Bar patent reforms in 2013 there has been a potentially fatal trap in the Australian rules relating to divisional applications. I have always thought it inevitable that someone would eventually fall into this trap – and practically certain that when it did happen, the applicant would be from the United States. A recent decision of the Australian Patent Office, in which a US-based applicant has been denied the opportunity to convert an application into a divisional of an earlier filing, in order to avoid having one of its own previous applications cited as invalidating prior art, has confirmed my prediction: Magnum Magnetics Corporation [2019] APO 3. Of course, this may not be the first time this situation has arisen. To the best of my knowledge, however, it is the first time it has resulted in an actual Patent Office decision highlighting the issue.In this recent case, Magnum Magnetics Corporation (‘Magnum’) filed an independent patent application in Australia when (as it subsequently turned out) the application should really have been filed as a divisional of an earlier application. So far, its efforts to correct this error have been unsuccessful.
As most readers will be aware, a divisional patent application is a type of patent application which is based on a previously filed application, commonly called the ‘parent’ application. A divisional application inherits the parent’s filing date and, to the extent that it discloses and claims subject matter that was also present in the parent, those claims are entitled to the same priority date. The primary purpose for which divisional applications were originally created was to enable further inventions that may have been disclosed in an initial application to be protected, since as a general principle a single patent may only claim a single invention. However, over the years many other practical and strategic uses of divisional applications have been developed. For example, it is permissible to update or add new subject matter in a divisional application, although any claims based on the added matter will not usually be entitled to the benefit of the parent’s priority date.
Historically, it has been very easy in Australia to convert between ‘regular’ and divisional applications, requiring only a straightforward amendment to the patent request. Such an amendment could be made at any time during the lifetime of the application/patent. However, the Raising the Bar reforms changed the rules, adding additional restrictions on when an application may legitimately be converted to a divisional. These restrictions will rarely be an issue for applicants that are making appropriate and well-informed use of the Australian patent application system. However, a failure to appreciate the limitations of the Australian system – and, to be honest, this is something I have seen on a number of occasions from US practitioners, since their system is quite different – can get an applicant into trouble.
Unfortunately, this appears to be what happened to Magnum, although I think that there may still be some hope of saving its application.

