The Full Federal Court has confirmed that if a patent specification contains a composite promise for an invention, a failure to attain any one of the elements of the composite promise in any claim will render that claim lacking in utility. However, while the decision in ESCO Corporation v Ronneby Road Pty Ltd [2018] FCAFC 46 confirmed the legal approach adopted by the judge below, its application of that test resulted in a finding that the claims in issue did not lack utility.

The Full Court reviewed a number of authorities dealing with the test for utility, ultimately concluding that if, properly understood having regard to the whole of the specification including the claims, a patent contains a ‘composite’ promise, a claim must meet each element of that composite in order to be useful. The question then was – what is the promise for the invention?

The judge below had held that paragraph 6 of the specification contained a composite promise by stating that:

“The present 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.”

The Full Court found that this language was used to recite those things to which the invention related, identifying the topics or subject matter of the invention rather than ‘promises’ for it. It placed significance on the fact that none of the paragraphs of the specification describing various embodiments of the invention sought to come to grips with describing aspects that captured each and every one of the features recited in paragraph 6.

It was also noted that in order to determine the promise of the invention, it may be necessary to have regard to the claims to determine which promise found in the specification was relevant to those claims. This was particularly so where the specification described a number of aspects of an invention, only some of which were the subject of the claims. The Full Court identified statements in paragraphs 15 and 16 of the specification which it found contained the promises relevant to the aspect of the invention as claimed.

Although the decision permits a more flexible approach to determining the promise of an invention by reference to the claims, patentees must continue to take care in describing outcomes said to be achieved by their inventions.