Intellectual Property Law Update When “opposites” attract infringement

Intellectual Property
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M Marcus
C Cunliffe 2
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Illinois Tool Works Inc v Airco Fasteners Pty Ltd [2022] FCA 495

Patents – where invention claimed is a fuel cell for use in a combustion tool – construction of patent – meaning of “close proximity” – meaning of “opposite”. Application for extension of time in which to file an appeal against decision of Commissioner to allow certain amendments to patent in suit. Application for judicial review decision to amend patent (and extension of time in which to lodge said application).

Federal Court


This patent infringement case concerned Illinois Tool Works’ patent claim to a metering valve used in fuel cells that provide a dose of fuel into a combustion chamber of, for example, a nail gun. The case turned primarily on the proper construction of the patent claims, including the meaning of the terms “opposite” and “close proximity”. There was also an attempt by Airco to seek judicial review of an amendment made to the patent some years before. Justice Rofe found that Airco’s products infringed Illinois Tool Works’ patent and that it was unnecessary to engage in a review of the amendments to the patent which concerned additional patent claims to those found to be infringed.


A popular form of nail gun uses a controlled explosion to provide the necessary force to drive a nail into wood. The explosion occurs in a combustion chamber which, in order to work safely and consistently, must receive a particular amount of propellant from a separate storage tank, or “fuel cell”. Broadly, the invention described in Illinois Tool Works’ patent is such a fuel cell which includes an internally mounted metering valve arranged such that a measured dose of fuel is dispensed each time the stem is pressed into the “open” position. The patent also explains how the invention can be used in relation to cosmetics – a somewhat frightening proposition.

Claim 1 of the patent provided for a (emphasis added):

“fuel cell for use with a combustion tool, comprising:

a housing defining an open end enclosed by a closure;

a main valve stem having an outlet, disposed in operational relationship to said open end and reciprocable relative to said housing at least between a closed position wherein said stem is relatively extended, and an open position wherein said stem is relatively retracted;

a fuel metering valve associated with said main valve stem, including a fuel metering chamber disposed in close proximity to said closure and configured so that when said stem is in said open position only a measured amount of fuel is dispensed through said outlet;

said housing including a separate fuel container,

wherein said fuel metering valve is located within said housing and includes a valve body having a second end opposite said fuel metering chamber located within said container, and wherein the flow of fluid out the outlet of the fuel cell is solely from said separate fuel container.

The bolded terms above were those which Airco contended meant its product did not infringe the patent. While her Honour addressed the question of construction of the claims of the patent before revealing the detail of Airco’s allegedly infringing fuel cell, in order to understand why these bolded terms were important, it is worth explaining why Airco said its fuel cells were arranged such that they did not infringe the claim. An Airco fuel cell is depicted below. Importantly, the fuel metering chamber is positioned at the end of the fuel metering valve which is furthest from the closure.

Fig 1

Her Honour rejected Airco’s contention that “in close proximity” has the same meaning as “closely proximate” or “adjacent or next to”. Her Honour found that the requirement that the fuel metering chamber be disposed in “close proximity” to the closure is “to be determined by assessing the relative locations of the fuel metering chamber and the closure within the context of the fuel cell as a whole, with the two components being sufficiently nearby or close to each other in that context that the same measured dose of fuel is dispensed for each combustion event”. Unsurprisingly, her Honour found that the Airco’s fuel metering chamber was in “close proximity” to the closure.

Next, her Honour considered whether the Airco fuel cell’s “fuel metering valve … includes a valve body having a second end opposite said fuel metering chamber located within said container.” Airco contended that the meaning of the word “opposite” in claim 1 was to be assessed by determining whether the fuel metering chamber is located closer to the identified “first” end of the valve body, being a fixed location, in other words, at the other end of the valve body to the first end. Illinois Tool Works contended that the question was whether the second end of the valve body is “opposite” the fuel metering chamber in the sense of “facing” or “across from it”, which involves a spatial relationship between the two identified objects.

The patent appeared to use the word “opposite” consistently to mean at opposing ends of a particular object. Furthermore, the preferred embodiment in the patent shows the fuel metering chamber being in the top end of the valve body (ie, at the opposite end to the lower/second end of the valve body), consistently with Airco’s construction. However, her Honour noted that the claim is describing the relationship between two objects – the valve body and the fuel meting chamber, and so need not be using the term “opposite” consistently with the description of a single object. Furthermore, her Honour observed that when the word “opposite” is used to define the relationship between two separate objects, that does not convey that those objects are as far away from each other as is possible. Her Honour gave the example of two people sitting opposite each other at a table.

The difficulty for Airco may have resided in the fact that the claim defines where the second end of the valve body is by reference to the position of the fuel metering chamber (which is not previously identified as being in a particular position) rather than, for example, saying that the “fuel meting chamber is within the valve body and opposite to the second end of the valve body”. While her Honour accepted Illinois Tool Works’ construction of “opposite” we note that, at least on the passages from the patent identified in her reasons, minds could reasonably differ.

It will be interesting to see whether Illinois Tool Works appeals this decision based on construction, and whether the Full Court would supplant Rofe J’s view, which is an evaluative one of a primary judge, even if it concluded that it might take a different view.

Given the finding that claim 1 was infringed, her Honour did not need to grapple with Airco’s complaints about amendments made to add claims 17, 20 and 21 to the patent before the proceeding had commenced. Nevertheless, her Honour first observed that the only person having a right under section 104(7) of the Patents Act 1990 (Cth) to appeal a decision of the Commissioner to allow an amendment to a patent, is a person who opposed the making of the amendment in the first place. Accordingly, Airco’s application for an extension of time within which to file a notice of appeal from the Commissioner’s decision was futile. We note that the extension of time that Airco likely needed was one in which to file a notice of opposition to the grant of the amendments (although it did not apply for it).

Justice Rofe also dismissed Airco’s application for an extension of time under rule 31.02 of the Federal Court Rules within which to lodge an application for an order of review under section 11(1)(c) of the Administrative Decisions (Judicial Review) Act 1997 (Cth), to review the Commissioner decision to allow the amendments. Given Airco had not provided any explanation as to why it had not availed itself of the right to oppose the amendments when allowed by the Commissioner, her Honour concluded that it was unlikely that an extension of time would be granted.

Finally, Rofe J also dismissed Airco’s application pursuant to section 39B of the Judiciary Act 1903 (Cth) for review of the Commissioner’s decision to amend the patent. Her Honour observed that non-compliance with section 102 and 104(5) of the Patents Act does not render the Commissioner’s decision to allow amendments, invalid. In particular section 26(2) provides that a patent is not invalid merely because an amendment of the specification has been made that was not allowable. In the present case, her Honour observed that, although there is no prescribed time limit in which to bring an application under section 39B of the Judiciary Act, the remedies available are discretionary and delay can be a relevant factor in refusing relief.

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