Engineering patent law 101 – 2 February 2016
A recent decision  of the Full Federal Court  provides a lucid tutorial on various oft-debated aspects of Australian patent law pertinent to engineering inventions.
Two innovation patents were in issue. Both claimed a garden hose that increased in length under the influence of the water pressure within. Whilst the patentee has thus far prevailed, (in the glare of hindsight) it is clear that the patentee would have been better served by claims that were worded differently, and the infringing party has applied for leave to appeal to the High Court  so the patentee is not out of the woods yet. The case serves as a useful reminder for patent draftsmen.
‘A garden hose’ is construed  as ‘a hose capable of being used as a garden hose and performing the functions one would ordinarily expect a garden hose to perform’. The decision not only confirms that under Australian law the preamble to a patent claim is limiting but goes on to demonstrate that the preamble can itself constitute a characterising feature sufficient to sustain at least an innovation patent.
‘Between [the ends of the hose]’ is construed as ‘within the hose’.  Scope to argue as to the interpretation of ‘between’ in a patent claim seems inescapable. Whilst the patentee won the argument on this point, the argument could have been avoided by the inclusion of the less-debatable wording ‘within the hose’ or similar.
A stepwise approach to the innovative step  assessment is provided and it is made emphatically clear that there is no need for the departure from the prior art to be ‘great’, ’weighty’ or even advantageous.
A tension between purposive vs literal claim interpretation is resolved in the patentee’s favour. One of the claims in question specified that a ‘fluid flow restrictor creates an increase in water pressure’ and ‘said increase in water pressure expanding [various components] and thereby substantially increasing a length of said hose’ (our emphasis).
The majority  note that this is an exceptional case  and opine  that the Judge of first instance was correct to construe the underlined wording as ‘a reference to the overall increase in water pressure within the hose resulting from the tap turned on’.
The case is a reminder that:
- whilst Australian courts have consistently warned against over-meticulous verbal analysis, meticulous analysis is called for at the drafting stage; and
- in the context of a freedom to operate assessment, one cannot disregard a competitor patent on the bases of ‘some literal and grammatically parsed constructions devoid of practicality and context’. 
Our patent attorney engineers are ideally placed to advise on the foregoing matters.
 The court of first appeal for Australian patent matters
 Australia’s most authoritative court
 At paragraph 47
 At paragraph 65
 An innovative step is to an innovation patent as an inventive step is to a standard patent
 Justices Kenny and Beach
 At paragraph 111
 At paragraph 94
 Words drawn from paragraph 26