What you need to know
- Patents are required to disclose the best method of performing the invention known to the patentee at the filing date.
- BlueScope's alloy-coated steel patents referred to a method requiring "special operational measures". The Federal Court found that BlueScope did not disclose those measures in sufficient detail.
- BlueScope was not permitted to amend its patents to overcome the lack of disclosure for discretionary reasons, including that BlueScope's failure to disclose the best method had given it an unfair advantage to the detriment of the public.
What you need to do
- Patent applicants should ensure that their patent applications clearly disclose the best method of performing the invention known to them at the filing date.
- If you become aware that your patent may not have disclosed the best method, seek to amend it promptly.
Background
BlueScope Steel Limited (BlueScope) owned Australian Patent Nos. 2009225257 (the 257 Patent) and 2009225258 (the 258 Patent) relating to alloy-coated steel strips and methods of producing them. The methods were directed to controlling the degree of variation in the coating thickness, so that there is only a small proportion of magnesium silicide at the surface of the coating.
BlueScope commenced infringement proceedings against Dongkuk Steel Limited (Dongkuk), which imported and sold in Australia a magnesium alloy galvanised steel product. Dongkuk counterclaimed that BlueScope's patents were invalid.
In December 2019, Justice Beach found that Dongkuk did not infringe BlueScope's patents, and that BlueScope's patents were invalid for not disclosing the best method of performing the invention known to BlueScope at the filing date.
The best method requirement
The Patents Act 1990 (Cth) (the Act) requires a patent specification to "describe the invention fully, including the best method known to the applicant of performing the invention" at the filing date. The best method requirement does not require absolute disclosure. It does, however, require enough disclosure so that the skilled addressee can arrive at the best method using routine experimentation, and without ingenuity or undue experimentation.
BlueScope's failure to disclose the best method
The 257 Patent required that "special operational measures" be implemented to keep coating thickness variation under control. However, the 257 patent did not disclose what these special operational measures were. Because the nature of the invention was to keep short-range coating thickness variations below 40%, which required special operational measures to be applied, disclosure of these special operational measures was important. Justice Beach found that, at the filing date, BlueScope knew of four specific operating measures that constituted "special operational measures".
Justice Beach agreed with Dongkuk that there were four reasons demonstrating that BlueScope failed to disclose the best method known to it:
- A skilled addressee would not have understood what "special operational measures" meant in the context of the specification.
- Even if the best operating measures formed part of the common general knowledge, a skilled addressee would not understand the 257 Patent to be referring to those measures, due to the use of the word "special".
- A skilled addressee, even if they were aware of a number of different operating measures, would not be aware of the particular four special operational measures known to BlueScope.
- Neither electromagnetic stabilisers nor air flotation stabilisers, which part of the special operational measures known to BlueScope, formed part of the common general knowledge at the filing date.
It was notable that none of the independent experts in the proceeding would have applied the four particular special operational measures known to BlueScope. Each expert outlined a different set of operational measures to control coating thickness variation.
Even though BlueScope didn't actually produce a commercial product using the 257 patent until 2013, Justice Beach found that its failure to disclose the best method at the filing date in 2009 meant that the 257 patent was invalid.
Justice Beach found the 258 Patent to be invalid on the same basis, despite it not actually using the term "special operational measures". This is because the 258 patent involved the same requirement to control the coating thickness, but did not disclose the best operational measures known to BlueScope for doing so.
BlueScope's amendment application
As part of the same proceeding, BlueScope applied to amend the 257 Patent to specifically disclose the "special operational measures". Justice Beach refused BlueScope's amendment application on discretionary grounds.
Justice Beach considered the following circumstances were relevant:
- the issue of "special operational measures" not disclosing the best method was flagged in the examination report for the 257 Patent, and for similar patents in China, Japan, South Korea and the US;
- BlueScope's lawyers raised the issue around "special operational measures" in 2016, putting BlueScope on notice that the patent may be invalid;
- the amendment request was not made until nearly ten years after filing, some four years after the grant of the patent and two years after the commencement of an infringement proceeding; and
- BlueScope had obtained an unfair advantage to the detriment of the public by failing to disclose the best method and exploiting its statutory monopoly in the meantime.
Justice Beach found that BlueScope knew or ought to have known that the patent did not disclose the best method when it threatened Dongkuk with an infringement proceeding. His Honour concluded:
"At the least BlueScope had constructive knowledge of the need to amend the specification well before it did so and simply made a calculated decision to take its chances with the disclosure it had made, whilst simultaneously benefiting commercially from the best method to the detriment of the public".
Authors: Ian Harris, Lawyer; and Stuart D'Aloisio, Partner.
