Australia: Australia´s Highest Court Just Made It Harder To Invalidate Patents

Last Updated: 24 May 2007
Article by Duncan Bucknell
Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [2007] HCA 21
Copyright Wednesday, May 23, 2007 Duncan Bucknell
Take home

Earlier today (23 May 2007), a unanimous Australian High Court handed down the long-awaited decision in the Lockwood v Doric patent dispute.

For those who aren’t patent lawyers - the decision means that it is now harder to invalidate patents in Australia as an often relied upon attack (the ‘Threshold Test’) has been all-but removed, and the requirements for proving obviousness are now more difficult.

Having said that, the decision has brought Australia into better alignment with many other jurisdictions, by putting admissions in a patent specification into proper context and by (all but) removing the ‘Threshold Test’ of inventiveness.

For those in patent law - in relation to obviousness, the court stated (some would say restated) that:

obviousness is a question of fact;

‘obvious’ means ‘very plain’

a ‘scintilla of invention’ remains sufficient in Australian law to support the non-obviousness of a patent;

in contrast to the situation in Europe, the ‘problem-solution’ approach may be useful but is not determinative of obviousness under Australian law;

admissions made in a specification about prior art and common general knowledge are not determinative of their contents, but must be weighed against other evidence presented to the court (such as that from technical experts);

the role of secondary evidence (such as commercial success, satisfying a long-felt want or need, the failure of others to find a solution to the problem at hand and copying by others) should not be discounted in obviousness cases (secondary considerations have been used to great effect in the USA).

In addition, the Court held that the infamously confusing Australian ‘Threshold Test’ of inventiveness does not exist. In the words of the Court: "The decision in Microcell has not always been properly understood; it does not involve a separate ground of invalidity or a discrete "threshold" test."


The decision reinforces the differences between Australian law and that of Europe in which the ‘problem-solution’ approach prevails. This is not to say that the problem-solution approach shouldn’t be used in Australia, just that it isn’t determinative.

On the other hand, in the USA, secondary considerations are oft-cited in obviousness arguments and litigants can expect their prominence to increase in Australia in light of this decision.

Admissions made in a patent specification have at last been put in their proper context by this decision. Based on the Wrigley and BMS decisions, there has been a widespread view that the content of such admissions was unchallengeable.

The Threshold Test

Another nail in the coffin of this infamously confusing test can only be a good thing. The test exists no where else in the world (as far as I am aware), and came about by misinterpretation of obiter comments in earlier decisions in different contexts. While the High Court has clearly stated here that there is no such test, there is High Court authority that could be used to argue against this position, and the comments in this decision were not part of the ratio.

Section 7(3) prior art

Under Australian law, obviousness is tested against (a) the common general knowledge of the person skilled in the art either alone or combined with (b) prior art information that could reasonably have been ascertained, understood and regarded as relevant by the person skilled in the art. The High Court made some confirmatory observations about the operation of this section which are also well worth a read. Most interesting of these is that ‘regarded as relevant’ for the purposes of this test may vary with each claim in a patent.

Background to the patent and the invention

The priority date of the Patent is 14 February 1996. The application for the Patent was filed on 11 February 1997 and Lockwood was entered on the Register as the proprietor on 2 November 2000. The Patent claims a "key controlled latch":

"This invention relates to latches of the kind which are controlled by a key operable lock and which are intended for use on doors and other movable members adapted to close an access opening ...

Latch assemblies for doors commonly include a turn knob or handle which is generally located at the inside of the door and which is rotated to withdraw the latch bolt into its casing. In order to improve the security of such assemblies, manufacturers have included a key operated lock which is operative to releasably hold the turn knob or handle against rotation."

The specification further explains:

"Such locks are typically arranged so as to be operated from the inside of the door and are not operable from the outside of the door. In particular, key operation of the latch from the outside of the door will not release the lock. That can lead to serious problems in circumstances where the door needs to be opened urgently from the inside, particularly if the lock key has been misplaced or is not conveniently accessible.

It is an object of the present invention to provide a key controlled latch which can be released from a locked condition by use of a key at the outside of the door or other member with which the latch is used."

The litigation

The proceedings were commenced on 12 October 2000. Doric, sought relief under s 128 of the Patents Act 1990 (Cth) ("the Act") on the grounds that Lockwood had unjustifiably threatened Doric and its two distributors with infringement proceedings. Lockwood cross-claimed against Doric for infringement of the Patent; in a second cross-claim Doric sought revocation of the Patent on the basis that it was invalid.

For a copy of the decision, click here.

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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