During the 1990s Australian courts have focused more closely on the wording of patent specifications when assessing validity. In many cases, granted claims have been held to be novel and inventive but nevertheless invalid due to the failure of the claims to comply with section 40 of the Australian Patents Act 1990. Section 40(2) requires that a complete specification 'describe the invention fully, including the best method known to the applicant of performing the invention' while section 40(3) requires that 'the claim or claims must be clear and succinct and fairly based on the matter described in the specification'. While it is possible to amend a patent specification during infringement proceedings, an Australian court has the discretion to refuse the amendments1 and there are also issues regarding recovery of damages before amendments.2
In order to minimise the risk of patent invalidity, a number of concerns should be addressed during patent prosecution.
The meaning of 'comprising'
The debate on the interpretation of 'comprising' in patent claims was recommenced in the 1990s with the Asahi v Grace decision.3 Recent judgments4 by the Australian Federal Court have continued the debate for both mechanical and chemical inventions and have highlighted the potential dangers when using 'comprising' in Australian patent claims.
There are three possible interpretations for the term, namely, an inclusive meaning, 'include', or an exclusive meaning, 'consists of' or indeed may be ambiguous. Giving 'comprising' an inclusive meaning provides the broadest definition of an invention but may lead to the claim being held invalid as not being 'fairly based' if all of the essential integers are not recited in the claim or the description in the specification does not provide adequate information about other materials or integers which may be included. On the other hand, the difficulty with providing an exclusive meaning to 'comprising' is that the scope of the invention is narrower and non literal infringement arguments may be required for a successful infringement action. However, an exclusive meaning usually improves the prospects of the claim complying with section 40. The use of the term 'comprising' has not generally been held to be ambiguous and thus lack of clarity is usually not a problem.
Irrespective of which meaning is intended, in order to avoid ambiguity, it is important that the term is used consistently throughout the description and claims. While in the majority of cases the meaning of 'comprising' will be inclusive, to avoid the possibility of introducing inconsistencies into the specification, we would advise against the addition of an inclusive definition clause at the time of filing.
In most cases the meaning of 'comprising' can be ascertained from the specification, and if clarification to remove inconsistencies or ambiguities is required, amendments can be made. As this important task requires a good understanding of the invention, we recommend that clarifying statements or definitions, if required, be inserted during the examination process rather than at the time of filing. We also recommend that, before infringement proceedings are initiated, the specification be thoroughly reviewed with respect to section 40 issues so that amendments, if required, can be undertaken before the action is commenced.
Under Australian drafting practice, statements corresponding to at least the independent claims are often included in a patent specification at the time of drafting. These 'consistory' statements assist in establishing that the claims are fairly based on matter described in the specification.
During examination, however, the claims are frequently modified. In a recent Australian Federal Court decision,5 an apparently slight inconsistency between the definition of a feature in the claims ('fluid pervious') and the description of that feature in the body of the specification ('vapour and/or fluid permeable') resulted in the Court finding that the claims were invalid since the invention as claimed was not fully described in the specification. In this case, the claims were novel, inventive and infringed but the patent was invalid because of the inconsistency between the essential features and terminology in the description and the defined features of the claims. Had a consistory statement corresponding to at least the claims been inserted into the description as the Summary of the Invention during examination, or at least prior to the commencement of the infringement action, it is likely that the invention would have been considered to have been fully described and hence valid.
We therefore strongly recommend the introduction of consistory statements corresponding to at least the independent claims, as accepted for grant, during the examination process.
Foreign patent specifications frequently include a number of sentences setting out several aims or objects of the invention. This practice is particularly useful in the prosecution of patent applications before the European Patent Office and the USPTO. In European patent applications, for example, such sentences are used to set up several problems with the existing prior art. Since the independent claims in such applications must include all features essential to solving only one of the problems of the existing prior art, as described in the specification, the inclusion of several object statements provides for greater flexibility in claim amendment during the examination procedure.
However, under Australian practice, the object statements serve a very different purpose. If a claim in an Australian patent specification does not include all essential features of an invention, it is not fairly based and will fail to comply with section 40(3). These integers which constitute 'the essential features of an invention' are determined by a more literal analysis of the patent specification. Any statement—such as an object statement—in the specification that points to a result that the invention is said to achieve can be interpreted as meaning that the features that enable the invention to achieve that result are essential to the invention. The inclusion of several such statements in the specification can mean that every feature required to achieve the result of all object statements are essential features of the invention, and independent claims which do not fulfill all of the objections and by implication include all of the essential features required to fulfill all of the objectives, will be held to be invalid. The Australian Patent Office has held that features relating to all aims of an invention should be included in all independent claims.6
We therefore recommend that during the examination process all but the most general of object statements be either deleted, or amended so that the results sought are no longer aims of the invention but merely desirable features.
The death of modified examination?
It is possible to request either ordinary or modified examination of an Australian patent application. If modified examination is requested, the specification of the Australian patent application must be brought into exact conformity with a granted corresponding United States (US), United Kingdom, Canadian, New Zealand or English language European patent. A simplified form of examination is then conducted by the Australian Patent Office, which does not include matters under section 40 but does include novelty and lack of inventive step.
However, as discussed in earlier points, the foreign patent upon which modified examination is based may not be in compliance with Australian requirements for fair basis and clarity, and any Australian patent subsequent granted may be inherently invalid.
Other problems can also arise. Consider the following scenario: an Australian patent application may have resulted from the national phase entry in Australia of a PCT application, claiming priority from a US basic patent application. The US claims are then narrowed under US examination but in accordance with US practice the body of the specification is not amended to reflect the narrower claims. Under modified examination no amendment is allowed of the body of the specification and this may lead to the patent ultimately being held invalid as the description is inconsistent with the claims.
We therefore strongly advise against requesting the modified examination of Australian patent applications.
Limited ability to amend post-grant
Although an application has been accepted there are additional restrictions in the scope of the amendments allowed. In particular, amendments that lead to a broadening of the claims is not allowed except for amendment of clerical or obvious errors. After grant the written consent of any registered mortgagee or licensee is also required. If legal proceedings have commenced amendments may only be made by an order of the court and thus is a discretionary power.
A further limitation in post-acceptance amendment is that section 115(1) provides that damages shall not be awarded in respect of any infringement of the patent before the date of the decision or order allowing or directing the amendment unless the specification was framed in good faith and with reasonable skill and knowledge. This may present problems.
In summary, it is best to amend the specification if possible before acceptance and normally this would be during examination. If after acceptance amendments become necessary to ensure the validity of a patent, these should be carried out as soon as practicable and certainly before infringement action was commenced.
During the examination process of an Australian patent application, careful attention must be paid to the construction of the description and the claims. Failure to appropriately amend the claim language, object statements and consistory statements, when required, can result in an invalid patent.
1Patents Act 1990 section 105.
2Patents Acts 1990 section 112.
3Asahi v WR Grace (1991) 22 IPR 491.
4General Clutch Corp. v Sbriggs Pty Ltd (1997) 38 IPR 359; Bristol-Myers Squibb Company v FH Faulding and Co Ltd (1998) 41 IPR 467; Mond Nickel Co Ltd's Application  RPC 189.
5Arico Trading International Pty Ltd v Kimberly-Clark Australia Pty Ltd  FCA 1191.
6Avid Marketing Inc. v Microchip Identification Systems Pty Ltd (1999) APO 37.
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.