By Alison McMillan PhD

Australian Patent law has a requirement not found in other major patent jurisdictions.  A patent applicant is obliged to disclose “the best method known to the applicant of performing the invention”.  Failure to do so is a ground of refusal or revocation.


Section 40(2)(aa) of the Patents Act 1990 requires that “a complete specification must disclose the best method known to the applicant of performing the invention”. This is a distinct requirement to that of enablement, under Section 40(2)(a) that requires an invention must be described in a manner that is “clear enough and complete enough for the invention to be performed by a person skilled in the relevant art”.  Consequently, even if a manner of performing an invention is self-evident and could be performed by a person skilled in the relevant art without undue burden, applicants are nevertheless still required to set out the best method of performing the invention known to them.

Patent specifications drafted to meet the enablement or written description requirements of other jurisdictions may not be “best” in Australia.

Prior to the Raising of the Bar Act 2012, any alleged deficiency in a patent application in relation to the “best method” could be cured by amendment.  However, post the Raising the Bar Act, amendments to add a best method are not allowed.

Recent Case Law

The best method requirement has not often arisen as a ground of revocation before the Federal Court or as a ground of opposition before the Patent Office.  However, there have been two recent Federal Court decisions that have clarified the law in relation to best method.  The Patent Office has been so guided and has recently refused two patent applications on the basis of failing to disclose the best method.  It is important to note that in each case, the disclosure was considered sufficiently enabling.

Federal Court Decisions


Les Laboratoires Servier v Apotex Pty Ltd [2016] FCAFC 27 (8 March 2016)

The Patent at issue related to and claimed a chemical compound commercially sold under the name COVERSYL for treating hypertension.  Apotex Pty Ltd (Apotex) applied for revocation of the Patent.

The patent claims were directed to the compound only and did not include any method claims.  The specification described a general method of synthesising the compound but did not include specific parameters that guaranteed a result.

Apotex argued that the best method requirement was not satisfied.  Servier argued that as only the product was claimed, it was only necessary to disclose the best product.  The Court acknowledged that this may be the case in some instances, but was dependent upon the nature of the invention.  The Court held that by omitting sufficient description of the synthetic method used, the Applicant failed to disclose the best method of performing the invention.  The Patent was revoked.

Sandvik Intellectual Property AB  v Quarry Mining & Construction Equipment Pty Ltd [2016] FCA 236 (11 March 2016)

The Patent at issue related to extension drilling systems for making holes for roof bolts in mines.

In evidence, one of the inventors acknowledged that “designing an effective water seal was a real issue which needed to be overcome”.  Technical drawings that were available before the application was filed showed an improved water seal arrangement but were not included in the specification.  Further, the seal arrangement was not a limitation of any claim.

It was held that the best method of performing the invention known to the inventors included the improved water seal arrangement and that arrangement was not disclosed.  The Patent was revoked.

Patent Office decisions


Kineta, Inc [2017] APO 45 [Kineta]

The application in question included claims to anti-viral compounds and methods for their use.  The inventors had identified a pathway involved in regulating the immune response to RNA virus infections.  A lead anti-viral compound was proposed based upon its chemical structure.  The inventors’ outsourced synthesis of the lead compound to a third party.  The specification did not disclose any synthetic method at all, nor the name of the company.

The patent examiner objected to the application on the basis of a failure to disclose the best method.  After a number of unsuccessful rounds of argument Kineta requested a Hearing.

Kineta led evidence that a person of skill in the art would have appreciated how to make the compounds on the basis of the common general knowledge and the best method was thus implicitly disclosed.

The Hearing Officer rejected these arguments.  The Hearing Officer acknowledged that at the filing date, the Applicant did not know how to prepare the compounds.  However, it was considered that what Kineta did know was that the compounds could be purchased from the contractor and this information was not disclosed.  The application was refused.

Merial Inc v Bayer New Zealand Limited [2018] APO 14 [Merial]

The patent application related to a tablet formulation with anthelmintic activity for animal administration.  The problem solved was how to formulate a tablet with incompatible active ingredients.  Grant of a patent on the application was opposed by Merial Inc.

In evidence, the inventor provided evidence relating to how the rationale behind the invention and that his evidence reflected his knowledge at 20 December 2006 (the priority date).  The evidence also included the current manufacturing instructions.  The Hearing Officer was satisfied that the current manufacturing process had already been established by the filing date.  The Hearing Officer also determined that important features of the manufacturing process were not disclosed in the specification. The application was refused as failing to disclose the best method.

Take Home Message

Omission of a best method can have fatal consequences for patent applicants and patentees in Australia.

Applicants should be vigilant when filing an application having a priority claim to ensure that the specification discloses the current best method that may have progressed since the priority date.

For further information please contact IP Gateway Patent and Trade Mark Attorneys by telephone on +61 7 38083566 or email us at mail@ipgateway.com.au

Call Now