Make sure you put your best method forward

Madderns Patent & Trade Mark Attorneys


Madderns is a leading privately-owned Patent and Trade Mark Attorney firm based in Adelaide, providing specialized intellectual property services in Australia and internationally for over 50 years. Their experienced team, including experts with PhD qualifications, works closely with clients to protect their brands and technologies. Serving a diverse client base, Madderns offers strategic advice on patents, trade marks, designs, and domain names to ensure the long-term success of their clients' intellectual property assets in various markets.
When filing a patent application, make sure that the best method of performing your invention has been put forward.
Australia Intellectual Property
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When you're filing a patent application, are you ensuring that the best method of performing your invention has been put forward?

The sufficiency and support requirements under Australian patent law received a significant "upgrade" after the Raising the Bar (RTB) amendments1 were introduced to our Patents Act 1990 (Cth) in 2013. These changes were intended to bring the Australian patent specification disclosure requirements into line with the standards applied internationally in other major jurisdictions.

Perhaps not attracting as much attention as the new sufficiency and support requirements was the fact that the RTB amendments left unchanged the best method requirement under Australian law – the only change being to provide this requirement with its very own subsection.2 While Australia, New Zealand and the US (examination only) have a best method requirement, many major jurisdictions (eg, Europe, China, Canada, Korea, Japan and UK) do not, and so it is timely to review how the Australian Courts and our patent office (IP Australia) have applied the best method requirement in recent times.

Of potential concern to patent owners is the growing number of instances where a challenge to patent validity has failed in relation to assertions of lack of sufficiency and/or support, but succeeded in establishing that the specification was defective, and the patent invalid, due to the best method requirement not being satisfied.

Legal Principles and Some Key Decisions

Section 40(2)(aa) of the Act requires that a complete specification must disclose the best method known to the applicant of performing the invention. The onus lies with any challenger to establish lack of best method, and the balance of probabilities standard applies in both patent office and Court proceedings.3 What can be seen from the wording of the section 40(2)(aa) is that the best method enquiry is substantively a question of fact, ie, it is the applicant's subjective knowledge that is to be assessed as to what they considered to be the best method and then whether that has been relevantly disclosed in the specification. However, there is no requirement for the applicant to identify where in the specification the best method is disclosed, it is enough that it is disclosed.

The leading Australian case on best method is the Full Federal Court's4 decision of Les Laboratoires Servier v Apotex Pty Ltd ("Servier").5 Following a comprehensive review of the authorities, the Full Court set out the following principles that govern the best method assessment including:

  • that the policy reason behind the best method requirement is to allow the public the full benefit of that invention when the monopoly expires;
  • although there is no explicit requirement for a patentee to act in good faith, principles of good faith underlie the best method requirement;
  • the nature and extent of the disclosure required to satisfy the best method requirement will depend on the nature of the invention itself;6 and
  • the nature of the invention is as described in the whole of the specification.7

In Servier, the patent concerned was directed to a new salt of perindropril having pharmaceutical effectiveness for the treatment of heart issues, and the claims were directed to the particular salt.  The evidence established that the patentee knew of two particular methods for forming the relevant salt but the patent specification only referred to using "a classical method of salification of organic chemistry". The Full Court found that this limited disclosure did not provide the "certainty of method" to the skilled person who would be at risk of failure, given all the potential parameters involved in classical salification, and that the method known to the patentee should have been disclosed.8

In Dometic Australia Pty Ltd v Houghton Leisure Products Pty Ltd ("Dometic")9 the question of when the best method requirement is to be assessed for a divisional application was dealt with. At the outset it should be stated that for a standard complete application, and as a result of changes to the amendment provisions following RTB,10 the best method requirement must be met at the filing date of the complete application. This is both in terms of what was the best method known to the applicant at the filing date, and the patent specification as filed contains a disclosure of this best method. Under the more generous patent amendment provisions prior to RTB, it was possible for an applicant to later amend their specification to include the best method if it had been omitted at the filing date.

In Dometic, the Court confirmed that the correct date to assess what was the best method known to the applicant was the filing date of the complete specification, but then went on to find that in the case of a divisional application, this would be the filing date of the divisional application.11 Notably, this date could be a number of years after the original filing of any parent application, but in accordance with Dometic, any improvements to the best method that may have occurred subsequent to the original filing date should be included in the divisional application. To be noted is that Dometic is a decision of a single judge of the Australian Federal Court and the principle that the best method is to be assessed at the divisional filing date is yet to be tested at the appellate level.

Application of the Law – Some Example Decisions

From the principles expounded in Servier, the Court will look to the whole of the specification to determine the nature of the invention.

The case of Sandvik Intellectual Property AB v Quarry Mining & Construction Equipment Pty Ltd ("Sandvik")12 illustrates this point. The patent in Sandvik concerned a drilling system that involved multiple extension rods that in operation were connected together to advance the drill bit progressively into a rock formation. The assertion was that this patent failed to disclose the best method because the embodiments described in the patent specification failed to describe the latest iteration of a "sealing member" at the relevant time and this sealing member was important to deliver water along the drilling system to flush the drill bit.13

The evidence was that developing an effective water seal had been a real issue.14 Even though the sealing member was not a feature recited in the independent claims, failure to disclose the best "sealing member" was held to be a failure to disclose the best method known to the applicant given its actual importance in operating the drilling system.15 Sandvik is a clear warning that even though a component or feature may seem to be relatively mundane in the context of the invention, if the component is important in how the invention works in practice, then it is important that the latest design of that component be included in the as filed specification.

The case of Merial, Inc. v Bayer New Zealand Limited ("Merial")16 is a decision of IP Australia in relation to an opposition to a divisional patent application directed to a tablet formulation with anthelmintic activity for administration to an animal. The patent application was being assessed under the post RTB-enhanced sufficiency and support requirements and the disclosure was found to have met these enhanced requirements but ultimately failed for not meeting the best method requirement.

This matter was notable as it was evidence that was led by an inventor on behalf of the applicant that was most telling, because in that evidence the inventor emphasised important process requirements in the formulation of the tablet that were known to the applicant.17 These details, however, were not evident in the specification, and it was found that the skilled person would have as a result assumed that conventional tableting methods were to be used.18 But again, on the inventor's own evidence, these conventional tableting methods would not have yielded a tablet having the improved stability and bioavailabilty features arising from the undisclosed method.19 It followed that a better method of performing the invention than that disclosed in the patent specification was known to the applicant, and so the patent application could not proceed to grant because it did not satisfy the best method requirement.20

In Blue Scope Steel Limited v Dongkuk Steel Mill Co., Ltd (No 2) ("BlueScope")21, the Court assessed two patents directed to the coating of steel strips with a coating of aluminium, zinc, silicon and magnesium (Al-Zn-Si-Mg). Of importance in the claimed invention was the requirement to restrict the short-range coating thickness variations within a maximum percentage over a specified area. The specification referred to the issue of short-range coating thickness variation in the same terms as the claims but only to the use of "special operational measures" to control this thickness variation without providing any further detail.

Following an assessment of the evidence, the Court found that the best method known to the patentee at the relevant date was the use of four different operating measures22, but the skilled person would not understand the reference to "special operational measures" in the specification to be referring to these four specific measures. This finding refuted an argument by the patentee that these measures formed part of the common general knowledge.23 Echoing the good faith principles that inform the best method requirement, the Court was quite critical of the patentee because it had confidentially used the best method while simultaneously benefiting from the statutory monopoly.24 This was another example where the patents met the requirements for sufficiency but were found invalid because of the failure to disclose the best method.

Given the potential stringency of the best method requirement, the question arises whether the failure to disclose a commercial embodiment of the invention, in those circumstances where it is available, would necessarily result in the best method requirement not being met. This issue was considered in GlaxoSmithKline Consumer Healthcare Investments (Ireland) (No 2) Limited v Generic Partners Pty Limited25 ("Glaxo") where the patent concerned was directed to an improved paracetamol formulation and where on the evidence the details of the commercial embodiment were available to the patentee at the filing date. In this case, an optimised process for forming the claimed paracetamol formulation had been provided as part of a regulatory approval submission, but this optimised method was not disclosed in the specification. The Full Court in Glaxo upheld the decision at first instance that there was sufficient disclosure in the patent specification.26

This decision was decided on its particular facts, but the Full Court maae some useful observations including that the question of whether the best method has been disclosed "should be addressed in a practical and common sense manner"27 and "[i]t does not follow merely because the patent applicant uses a particular manufacturing process or a particular excipient in formulating its commercial embodiment that it will form part of the best method".28 While in this case the patentee was able to survive the best method challenge, had the optimised method been included by the patentee, the risk of revocation on this ground would have been substantially reduced.


From this brief overview, the requirement to disclose in the patent specification the best method known to the applicant of performing the invention is critical. It is important to remember that it is the "nature of the invention" which governs what exactly needs to be disclosed, and this is a broader enquiry than the invention as narrowly defined by the claims.

When it comes time to prepare the complete specification, it is important that you as the applicant advise your Madderns patent attorney of the optimum implementation of the invention that is known to you at the time of filing the complete specification so that this can be described fully. Your Maddens patent attorney will advise you as to what level of detail is required. As can be seen from above, failure to describe the "best method" runs the risk that any patent based on the complete specification may be found to be invalid.


1Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth).

2 Section 40(2)(aa) of Patents Act 1990 (Cth).

3Section 49 of Patents Act 1990 (Cth).

4Full Court of Australian Federal Court which in Australia is broadly at an equivalent precedential level to the US Court of Appeals for the Federal Circuit in relation to patent matters.

5 [2016] FCAFC 27.

6 Servier at [108]

7 Ibid at [124].

8 Ibid at [173].

9 [2018] FCA 1573.

10 Section 102(1) of Patents Act 1990 (Cth).

11 Dometic at [230], [234].

12[2016] FCA 236.

13 Sandvik at [28], [29].

14 Sandvik at [221].

15 Ibid at [224].

16 [2018] APO 14.

17 Merial at [129] to [131].

18 Ibid at [135].

19 Ibid at [159].

20 Ibid at [160].

21 [2019] FCA 2117.

22 BlueScope at [884].

23 Ibid at [890] to [893].

24 Ibid at [956].

25 [2018] FCAFC 71.

26 GlaxoSmithKline Consumer Healthcare Investments (Ireland) (No. 2) Limited v Apotex Pty Ltd [2016] FCA 608.

27 Glaxo at [187].

28 Ibid at [201].

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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