Combination Patents: Smith & Nephew v Wake Forest University Health Sciences

In a recent decision, the Full Federal Court has set aside an interlocutory injunction granted against Smith & Nephew in June of this year. That injunction restrained Smith & Nephew from entering the Australian market for negative pressure wound treatment therapies. The case, Smith & Nephew v Wake Forest University Health Sciences, is interesting for the way in which the Court dealt with the interaction that is required between the various parts of a combination patent in order for the patent to be valid.

The invention in the case was directed to negative pressure wound therapy which utilises a suction pump to create negative pressure in the area of a patient’s wound and a foam dressing which is sealed in the wound by means of an adhesive dressing. The pump is then connected to the wound by tubing through which the negative pressure is applied.

Only one claim of the patent (claim 49) was in issue; it is directed to an “apparatus for applying negative pressure to a wound beneath a fluid-impermeable seal”. The wording of the claim details the various components of the apparatus and ends with the words “and wherein said apparatus is in an aseptic package”. This, in the Full Court’s view, was of crucial importance.

Importantly, it was not in dispute that the components (the “integers”) of the claim, apart from the aseptic package, do in fact interact to form “a new product and result”¹. It was also not in dispute that the aseptic package plays no part in the application of negative pressure to a wound.

Footnote

1. Smith & Nephew v Wake Forest University Health Sciences [2009] FCAFC 142 at [17].

The Full Court adopted the well-known formulations from Beecham Group v Bristol Laboratories and Australian Broadcasting Corporation v O’Neill as stating the principles to be applied in determining whether to grant an interlocutory injunction. Those principles can be stated as follows:

“The first is whether the plaintiff has made out a prima facie case, in the sense that if the evidence remains as it is there is a probability that at the trial of the action the plaintiff will be held entitled to relief ... The second inquiry is ... whether the inconvenience or injury which the plaintiff would be likely to suffer if an injunction were refused outweighs or is outweighed by the injury which the defendant would suffer if an injunction were granted.”

The Court noted that in determining whether a patentee has made out a prima facie case, the Court must consider both the patentee’s case for infringement and the respondent’s case for invalidity.

The Full Court considered that the primary judge (Ryan J) failed to consider, as a separate matter from novelty, whether claim 49 comprised a “mere collocation of separate parts” and was, therefore, invalid. This is relevant to the “manner of manufacture” requirement under the Patents Act 1990 (Cth).

Insofar as combination inventions are concerned, the claimed invention must reside in a combination of integers which in combination are not a mere collocation of separate parts but instead "interact to make up a new thing"². In Firebelt v Brambles Australia, the High Court confirmed that:

"… a combination patent in the proper sense of that term … combines a number of elements which interact with each other to produce a new result or product. Such a combination may be one constituted by integers each of which is old, or by integers some of which are new, the interaction being the essential requirement."

In the application before Ryan J, the patentee had argued that, as a matter of construction, the aseptic package is an “essential integer of the combination the subject of the claim”. The Full Court said, “[p]ut another way, the invention claimed by the respondents … included the package as an essential integer”³. The way in which the patentee put its case at first instance was of crucial importance to the Full Court’s decision on appeal.

The Full Court found that the aseptic packaging in which the wound dressing kits were sold did not interact with the other integers in the combination to produce the new result: being the application of negative wound pressure. The Full Court said:

“It is the mere bag in which the device that ‘does the work’ is stored before use. It is discarded before any negative wound pressure is applied. No doubt it is beneficial to have sterile packaging for a therapeutic device, however, the aseptic bag itself does nothing to cause, limit or affect the functional result of negative wound pressure as desired.”

In the Full Court’s view, this was determinative of invalidity. Once the aseptic package was said by the respondents to be an essential integer of the invention claimed, “it must interact purposefully and functionally with the other integers to produce the negative wound pressure”⁴. Its failure to do so meant that claim 49 did not disclose a combination invention in the proper sense of that term. As such, no serious question to be tried arose and the Full Court set aside the interlocutory injunction.

Footnotes

2. Firebelt Pty Ltd v Brambles Australia Ltd [2002] HCA 21 at [21].
3. Smith & Nephew v Wake Forest University Health Sciences at [19].
4. Smith & Nephew v Wake Forest University Health Sciences at [33].

There are difficulties with the way in which the Full Court dealt with the claim to the aseptic package. It is arguable that the Court placed too much importance on the patentee’s characterisation of the aseptic package as “essential”. Of course, claim construction is ultimately a matter for the Court.

In the course of its judgment, the Full Court referred to two earlier decisions: Pugh⁵ and British United Shoe⁶ which, at the very least, are in tension with the Full Court’s decision in this case. In essence, the Full Court distinguished those cases by saying that the language of the particular claim in issue is critical and, in this case, the aseptic package in the claim had been characterised as “essential”.

Despite this, it is clear that the claim in the present case disclosed an invention: a new apparatus formed by the interaction of the integers other than the aseptic package. However, for a third party to infringe that claim, the patentee must show that the alleged infringer has taken all of the “essential” integers of the claim. That would include the aseptic package. A third party can avoid infringement by not doing so. However, it is difficult to see how adding the aseptic package to the claim in the patent means that the claim no longer obtains a “new result”⁷.

On a separate issue, the Full Court usefully confirmed that Smith & Nephew had no legal obligation to “clear the way” for its product by first revoking the patent before entering the market. The Court noted that the fact that a potential infringer goes into a market with “eyes wide open” is simply a factor that a court would consider in making an assessment of whether or not to grant an injunction.

Footnotes

5. Pugh v Riley Cycle Co Ltd (1914) 31 RPC 266.
6. British United Shoe Machinery Company Ltd v Fussell & Sons Ltd (1908) 25 RPC 631.
7. In its judgment, the Full Court referred to the following comments in Bodkin C, Patent Law in Australia (2008) at [2440]: “Where a combination of features is claimed, one or more of which … is new, the claim is not invalid merely because one or more of the features has no working interrelationship with the new feature”.