27 October 2011

Contact Lens Cleaning Method ‘Inherently’ Anticipated by Prior Use

Abbott Medical Optics, Inc v Alcon Laboratories, Inc [2011] APO 79 (26 September 2011)

Opposition – novelty – whether claimed method anticipated by prior published instructions and prior use where benefits of method previously unrecognised – whether ‘strict proof’ of prior use required

contact_lensThis decision, issued by Delegate Dr B. Akhurst, concerns methods for the care of contact lenses.  In particular, the invention at issue is directed to the use of a single solution for cleaning and disinfecting contact lenses.

The interesting aspect of the decision is its analysis of novelty in the case that the claimed method may have been taught/performed before the relevant priority date, even though the actual inventive contribution or discovery of the later inventor may not have been previously disclosed or recognised.

In some other jurisdictions, such as the US, this situation would fall under the ‘doctrine of inherency’.  In Australia, there is no formal legal ‘doctrine’ of inherency although – as this decision demonstrates – this does not mean that it is necessarily possible to obtain a patent based merely on the discovery of a previously unknown property of a known process or composition.  In place of any distinct doctrine, the notion of inherency is itself inherent in the established tests for novelty of a claimed invention.


Patent application no. 2004201867, in the name of Alcon Laboratories, Inc (‘Alcon’), is entitled ‘Process for cleaning and disinfecting contact lenses’.  After the application was accepted (on 3 January 2008) it was opposed by Abbott Medical Optics, Inc (‘Abbott’).  As explained by the Delegate at paragraph [19] of the decision:

Before the priority date, products for treating contact lenses had generally been classified based on their intended use or function e.g. as cleaners, disinfectants, rewetting drops or conditioning solutions. Attempts to accomplish two or more functions with a single product had had limited success because combining components tended to reduce their effectiveness. As a consequence, from a purely scientific standpoint, this practice had been discouraged.

The contribution made by the Alcon inventors was discovery of a previously unrecognised property of solutions containing polycarboxylates/polycarboxylic acids, such as: citric acid and its sodium, potassium or ammonium salts or mixtures thereof; succinic, tartaric, malonic and maleic acids and salts thereof; ethanol diglycinate or diethanol glycinate.

Evidence filed in the opposition proceedings established that, before the priority date of the Alcon claims, it was known that a polycarboxylate solution is useful in the disinfection of contact lenses and/or as a storage solution for contact lenses.  However, it was not known that such solutions, particularly in preferred compositions disclosed in the Alcon patent specification, were also capable of removing tightly-adherent protein deposits by soaking over a period of a few hours.  As such, the inventors’ contribution was the discovery that polycarboxylate solutions could form the basis of a combined cleaning, disinfecting and soaking product.


Alcon’s accepted claim 1 reads as follows:

1. A method of cleaning a contact lens with a single solution comprising polycarboxylate(s) or corresponding acid(s) or a combination thereof in an amount effective to clean the lens, wherein said method comprises soaking the lens in the single solution for a time and under conditions sufficient to remove protein deposits attached to the lens wherein said time and said conditions do not only disinfect the lens or remove debris.

Other claims of interest for our purposes here are:
  1. claim 3, which requires the solution and the soaking step to be at a physiological pH; and
  2. claim 6, which adds a pre-treatment step in which the solution is applied to the lens for a time and under conditions sufficient to remove debris and disinfect the lens before soaking the lens in the solution.
The Delegate found that claims 1 and 2 each lacked novelty in view of either one of two US patents (nos. 4,599,195 and 4,808,239), both of which are also owned by Alcon, and name the same inventors as the opposed application.  Both documents were found to disclose the capability of polycarboxylate solutions to remove protein deposits, although neither disclosed any solution having a ‘physiological pH’.  As a result, all of the further claims were found to be novel (and inventive) over these US patents.


As explained in the USPTO Manual of Patenting Examination Procedure (MPEP), Section 2112, the doctrine of inherency may be summarised as follows:

[T]he discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art's functioning, does not render the old composition patentably new to the discoverer." Thus the claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable.

There is no requirement that a person of ordinary skill in the art would have recognized the inherent disclosure at the time of invention, but only that the subject matter is in fact inherent in the prior art reference.

Justice Bennett recently discussed ‘inherency’ under the Australian law in Danisco A/S v Novozymes A/S (No 2) [2011] FCA 282, stating (at [248]) that one circumstance in which an invention may be deprived of novelty despite the lack of any explicit disclosure in the prior art is when a ‘prior publication contains a direction to use a process that inevitably or inexorably results in something within the claim.’  

This is based on the decision in General Tire & Rubber Co v Firestone Tyre & Rubber Co Ltd (1972) RPC 457 (at pages 485-6), where it was stated that a claim would be anticipated if ‘carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim.’  General Tire also establishes that is ‘the prior publication contains a direction which is capable of being carried out in a manner which would infringe the patentee's claim, but would be at least be as likely to be carried out in a way that would not do so, the patentee's claim will not be anticipated’ (although it may nonetheless be obvious).

So while there is no distinct ‘doctrine of inherency’ in the Australian law, it is nonetheless an element of the long-established test for novelty.


Abbott relied upon Alcon’s earlier product Opti-Free® Rinsing Disinfecting and Storage Solution (‘Opti-Free® RDS’), and its accompanying instructions for use, as an anticipation of the opposed patent claims.

Opti-Free® RDS is a solution having a compositions falling within the terms of the claims.  It is/was sold with instructions directing the user to perform a three-step process of ‘clean’, ‘rinse’ and ‘store’.  The cleaning step utilises a specific cleansing product.  The rinse step involves applying a few drops of Opti-Free® RDS and rubbing the lens.  The relevant step in relation to the opposed patent claims is step 3, in which the user is instructed ‘to completely submerge the lens in the single Opti-Free® RDS solution and to soak for at least 4 hours or overnight.’

The Delegate considered that the performance of step 3 would inevitably fall within the scope of at least claim 1 if the lens was still in need of cleaning (i.e. if there were residual protein deposits) after the completion of steps 1 and 2 (see paragraph [71]).  In this case – albeit without necessarily being aware of it – many users would have been inherently performing the claimed method since before the priority date of the claims.

For a number of reasons – not the least of which being Alcon’s recommendation of a weekly clean with an enzymatic cleaner in order to remove residual protein build-up – the Delegate found that claims 1-5, 9 and 11-17 lacked novelty in view of the prior use, and publication of the corresponding instructions for use, of Opti-Free® RDS.

Other claims (such as claim 6) include additional steps not instructed in the Opti-Free® RDS document, and thus (presumably) not previously carried out.  Therefore these claims were found to be novel (and inventive).


Generally speaking, the burden of proving that a claim is not novel based on inherent aspects of a prior disclosure or use will lie with the party seeking to show that the claim is anticipated – particularly in opposition procedings. In this case, however, the burden of rebuttal shifted to Alcon, which had expressly declined to concede that Opti-Free® RDS was available before the priority date.

Once Abbott had provided prima facie evidence of the earlier availability of Opti-Free® RDS, the Delegate considered that the onus was then upon the applicant to establish any contrary facts since ‘Alcon, which developed and produced the product, should be in a unique position to know and be able to provide evidence as to when the product was available to the public’ (at [66]).  Despite having ample opportunity, Alcon failed to do so.


There is no distinct or formal ‘doctrine of inherency’ in Australian patent law.

However, the well-established tests for novelty do not require that all of the inherent effects and/or properties associated with following a particular procedure be known in order for there to be anticipation of a later claim which relies upon the discovery of those effects or properties to support patentability.  It is sufficient that the subsequently claimed process or result can be shown to have been practiced in the prior art, even if this can only be established on the basis of subsequent discoveries.

This is therefore one circumstance in which the evaluation of patentability may utilise hindsight, albeit in a strictly limited fashion.


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