Recent case law confirms the priority date of a divisional
patent application is the priority date of the parent patent
application.
Patents provide 20 year monopolies over inventions. However, to
be granted a patent, the invention must be new. This means that use
or disclosure of the invention to the public before the patent is
filed can be fatal to the patent application. Traditionally, a 12
month 'grace period' was allowed and that 12 months was
back-dated from the date that a patent application was filed.
In Mont Adventure Equipment Pty Limited v Phoenix Leisure
Group Pty Limited [2008] FCA 1467, which involved a subsequent
divisional patent application, the issue before the Courts was
whether that grace period for the divisional patent application
should be back-dated from the parent application (which is earlier
in time) or the divisional application (which is later in time and
therefore could potentially jeopardise the patent).
