We recently received a question from ‘James’ via the Ask Patentology page about the effect of ‘prior use’ of an invention on a subsequent patent obtained by somebody else. Although James elected not to leave an email address, we consider the topic to be of sufficient interest to warrant a post of its own.In a nutshell, the question is: how are the rights of a patent owner weighed up against those of other people or businesses, which may have been using similar technology for some time prior to the filing of the patent application, but which are then subsequently accused of infringing the patent? And how does this relate to the concept of ‘prior art’?
James was specifically interested in the case of a software-based invention, however the Australian patent law makes no distinction between different fields of technology. Nonetheless, it is probably fair to say that software inventions can, in some cases at least, be more easily ‘used’ without it necessarily being apparent how the software works, or what exactly it does, which has some impact on its prior art effect, so we will address this specific issue towards the end of the article.
The short answer is that under the Australian Patents Act 1990 a prior use of an invention might be used in one, or both, of two different ways to fend off an accusation of patent infringement. Firstly, it might be possible to employ the prior use as a form of prior art in order to attack the validity of the patent claims. Alternatively, section 119 of the Act provides that, in appropriate circumstances, the use of a patented invention before the priority date of the patent claims acts as a defence to an accusation of infringement.
There is also a ‘shortcut’ tactic, known as the ‘Gillette Defence’, which essentially says that if the accused infringer is doing nothing more than what was already done before the priority date of the patent claims, then either the patent is invalid, or the claims are not infringed. The defence runs that it does not matter which, because either way the accused is off the hook! This is a shortcut, because in principle it enables the court to dismiss a patent case without actually addressing the substantive questions of infringement or validity. There is, however, considerable doubt as to whether this is a legitimate form of legal reasoning under the current Act – quite aside from anything else, it has the potential to leave an invalid patent on the Register, to be used again another day! This issue arose in the recent Australian case of Otsuka Pharmaceutical Co., Ltd v Generic Health Pty Ltd [2012] FCA 239, which we wrote about in Australian Federal Court Blocks Generic ABILIFY (Aripiprazole), so we will not dwell on it again here.
Tags: Australia, Infringement, Prior art, Prior use defence
