Australian law requires that, in addition to being novel and inventive, a patentable invention must be ‘useful’. Although utility is not an issue considered during examination, lack of utility is a ground for opposition of an Australian application, as well as for re-examination and revocation of a patent.

The recent case of Ronneby Road v ESCO1 was an appeal to the Federal Court of Australia following an unsuccessful opposition to the grant of a patent application2 filed by ESCO Corporation (ESCO). Only one of the three different opponents, Ronneby Road Pty Ltd (Ronneby), appealed the decision, relying on the grounds of novelty, lack of fair basis and inutility.

On appeal, Jessup J considered all of the grounds and found that a number of the claims lacked novelty. He rejected the lack of fair basis allegation raised against certain claims. Significantly, Jessup J also considered the current law in Australia on the issue of inutility and found that all of the claims of the application failed the requirement to be useful, as set out in section 18(1)(c) of the Patents Act 1990.

The opposed application related to a wear assembly for securing a wear member to excavating equipment. In describing the background to the invention, it was said that:

‘Many designs have been developed in an effort to enhance the strength, stability, durability, penetration, safety, and/or ease of replacement of such wear members with varying degrees of success.’ 3

Further, the patent specification stated that the:

‘… invention pertains to an improved wear assembly for securing wear members to excavating equipment for enhanced stability, strength, durability, penetration, safety, and ease of replacement.’ 4

Ronneby argued that the promise of the invention (Figure 1) was therefore the achievement of all of these advantages. As such, these advantages were all to be delivered by the invention as claimed in each and every claim. On this basis, Ronneby submitted to the court that all of the claims of the patent application were:

‘… bad for want of utility because none of them delivered on the promise made in the specification, namely, that the invention would bring all of the six named advantages.’ 5

In response, ESCO argued that the advantages set out in the specification:

‘… were to be understood distributively apropos the claims that related to them respectively, rather than as a composite promise which conveyed the sense that all six advantages would be delivered by the invention so far as claimed in every claim.’ 6

In deciding this matter, Jessup J relied on the decision of Windeyer J in Pracades Pty Ltd v Stanilite Electronics Pty Ltd7. In that case, the patent specification listed six disadvantages of existing technology and promised that as a result of the invention these could largely be avoided. On the available evidence Windeyer J found that the invention did not fully deliver the promised result and that even a partial failure of the consideration given for the patent was sufficient basis for a successful claim for revocation.

Jessup J considered that he was bound to follow the authority of Pracades and held that all of the claims of the ESCO patent application were bad for lack of utility. ESCO has since sought leave to appeal the decision.

Irrespective of the outcome of the appeal, the clear message from this decision is to be very careful to ensure that a specification does not make promises for the invention which are not met by every claim. If certain advantages are only delivered by particular embodiments of the invention, then this should be made clear in the specification. Amendments to the specification to address the issue of utility should be made prior to grant of a patent on the patent application.