Australian Courts have repeatedly rejected1 the notion that what the applicant says during prosecution can be held against the patentee during later litigation. However, the general absence of a doctrine of prosecution history of estoppel in Australian practice should, in no way, be taken as tolerance by the Courts for representations which stray into misdirection.

This is well exemplified in the recent decision by the full Federal Court of Australia in Morellini v Mizzi Family Holdings Pty Ltd2 which highlights the extent to which Courts may go to revoke a patent under Section 138(3), if they believe it was granted due to false suggestion or misrepresentation.

The specification of Innovation Patent No 2010100955 (the patent) employed the phrase "It is found..." in a statement suggesting that a claimed feature of the invention provided a particular functional advantage. The Court took the view that the phrase implied the patentee had established a level of factual support between the feature and the advantage. Thus, when the statement was found to be merely conjecture on the part of the inventor, the Court revoked the patent.

Interestingly however, the feature related to the "false" statement was not that which conferred the invention with novelty and an innovative step over the prior art. Moreover, the statement was only relied upon by the patentee when responding to objections raised in respect of the parent standard application. Nevertheless, the Court was satisfied that the statement ultimately materially contributed to the Commissioner's decision to grant the subsequent innovation patent, thereby invoking Section 138(3) of the Patents Act 1990 (Cth).

The Dispute

Mizzi Family Holdings Pty Ltd (MFH) had sued Mr Morellini (Morellini) for infringement of their innovation patent entitled "A cane billet planter". Morellini denied infringement and filed a cross-claim seeking revocation of the patent on various grounds of invalidity, and damages for unjustified threats of patent infringement.

The primary judge concluded that no ground of invalidity had been established, but also that no infringement had been proved and so the claim of unjustified threats succeeded. Both parties appealed the decision.

Cane Billet Planter – "The Invention"

The patent is directed toward a method of planting sugar cane crops whereby short cuttings of sugar cane stalk, known as "billets" are laid horizontally on a prepared "bed" and covered with soil. The specification describes the need to properly position the billets to optimum levels of warmth and moisture so that they sprout and grow into cane plants. The invention also aimed at increasing the number of billets planted across the mound row in order to maximise planting and harvesting efficiency.

Claim 1 of the patent is directed toward a mechanised cane billet planter able to prepare a planting bed, plant the billets and cover them with soil to form a shaped mound, all in a single pass. In particular, the mound is shaped by a "mound profiler" adapted to provide the mound with a relatively flat top and "sides at an incline of between 20° to 60°".

Claim 4 also defines the shape of the mound however specifies that, "each side of the mound is inclined at an angle which promotes warming of the soil by the sun".

The judgment at first instance

The primary judge extensively examined the construction of these two claims, in view of an argument that the inconsistency indicated a lack of clarity and support. While the judge was able to resolve those issues, in the course of the analysis it was revealed by the patentee that the range of 20° to 60° recited in claim 1 was associated with the natural angle of repose of the soil rather than any warming effect by the sun. Armed with this evidence, and with reference to the specification, the primary judge concluded that any "warming effect" was instead due to the existence of the mound above ground level. The primary judge then turned to review novelty and innovative step.

Based on the evidence at hand, the novel difference between the prior art and the invention was regarded to reside in the sequence of steps involved in planting the billets and forming the mound. In the invention, the mound is formed after planting of the billets whereas the prior art indicated otherwise. Furthermore, since this difference substantially contributed to the working of the invention, the claims were seen to include an innovative step.

False suggestion or misrepresentation

On appeal, the Full Court agreed with both the reasoning and the decision of the primary judge on the issues of novelty and innovative step. However Morellini had also argued for revocation based on the ground of false suggestion or misrepresentation tied to the notion of an advantageous warming effect due to the angle of the sides of the mound. This relationship is promoted a number of times in the specification, for instance in a passage referred to as the "Statement":

"In one form, the invention resides in ... profiling the mound such that the soil about the billets [is] better warmed by the sun's rays ... It is found that the mound can be much better kept warm by the sun if each side of the mound is an [incline] of between 20-60° and typically about 40°"

Morellini argued that the Statement comprised representations that not only can the mound be much better kept warm by the sun given the specified angle of incline of the sides; but also, that experiments had been undertaken to establish this as fact.

In response, MFH relied on the primary judge's dismissal of the argument and submitted there to be some advantage in planting cane in a mound and that the "finding" to which the Statement refers is "readily capable" of being Mr Mizzi's own experience and conclusions. Significantly however, MFH did not provide any evidence supporting the Statement admitting they would need to do testing to provide the Court with such evidence.

MFH's response was rejected by the Full Court who determined that the Statement clearly conveys a relationship between the stated profile of the mound and the resultant "better warm[ing]" and advances it as a fact which has been "found". Furthermore, their Honours concluded that the representations were false at the time they were made.

Contribution

Having determined that the representations made were indeed false, the Court addressed the connection between those representations and the grant of the patent. In Ranbaxy Australia Pty Ltd v Warner-Lambert Co LLC3 it was found that a patent could be regarded as being obtained by a false suggestion or misrepresentation if the representation materially contributed to the Commissioner's decision to grant the patent – even if other circumstances or causes also played a part.

Turning to the background of the patent, the limitation that the formed mound be a "shaped mound in which each side of the mound is an incline of between 20° and 60°" was first introduced into the claims of the parent application as an amendment during the course of opposition proceedings. In support of the amendment, it was submitted to the Commissioner, that "the specification teaches that in order for the billets to be kept warm within the mound, the mound should have angled sides" and the Statement was referenced in support.

However the Court was not swayed by the degree of separation between the parent case and the patent, inferring that by association "MFH was intending to present the invention described and claimed in its divisional application as one that was both novel over (the prior art) and involved an inventive step." Thus that the Statement was intended to contribute, and did contribute, to the Commissioner's decision to grant the patent.

The appeal was allowed on the ground of false suggestion or misrepresentation.

Conclusions

Given that their Honours concluded that the representations were false at the time they were made and this is the appropriate time for assessing their truth, it goes without saying that experiments should ideally be undertaken to confirm statements made in a complete specification before filing a patent application.

However, this case is perhaps less relevant to instances of clear statements of advantage and the corresponding existence of hard experimental data. Rather, the decision sounds a note of caution to those drafting and reviewing patent specifications. While they might initially appear innocuous, there is little doubt that phrases such as "It is found..." are designed to impart a level of legitimacy to a perceived advantage of an invention or feature. If made without due consideration or a factual support, their inclusion may be ultimately self-defeating rather than advantageous, particularly if relied upon to establish patentability.

When presented with expected advantages provided by a particular invention, those who draft patent specifications should ensure they properly interview inventors and are fully apprised of the basis on which those advantages are put forward.

Footnotes

1 Bradken Resources Pty Ltd v Lynx Engineering Consultants Pty Ltd [2015] FCA 1100
2 Morellini v Mizzi Family Holdings Pty Ltd [2016] FCAFC 13
3 Ranbaxy Australia Pty Ltd v Warner-Lambert Co LLC (2008) 77 IPR 449

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