Purposive Construction Does Not Support “Any Arguable Interpretation That Would Uphold the Patent”

ABB Technology AG v Hyundai Heavy Industries Co, Ltd, 2015 FCA 181 Stratas JA: Webb, Near JJA aff’g 2013 FC 947 and 2013 FC 1050 (costs) Barnes J
            2,567,781 – 2,570,772

In my post on Barnes J’s decision in ABB v Hyndai 2013 FC 947, I remarked that it is “a fairly straightforward case which turned largely on its facts.” It is therefore not surprising that the FCA has affirmed the holding that both patents at issue are invalid, largely on the basis of a deferential standard of review.

The most interesting point was one of claim construction, which the FCA reviewed for correctness. The invention was a viewing window to allow visual inspection of the position of the grounding switch in gas-insulated switchgear. The crucial claim term used to describe the grounding switch was "a moveable switch-contact element" [32]. The patentee, ABB, acknowledged that the prior art disclosed the use of viewing windows to observe the position of knife blade switches [33] and argued that this term should be construed to encompass only sliding contact switches [33]. ABB argued that the principle that a claim should be required to “afford the inventor protection for that which he has actually in good faith invented” Consolboard ([1981] 1 SCR 504, 521) implies that an interpretation should be adopted which favours validity [50].

My post on the decision of Barnes J had a long (and now that I re-read it, somewhat convoluted) discussion of the possible tension between a purposive and textual analysis* of the claim. Whatever the merits of that discussion, the case at hand does not raise any such tension, because as Barnes J held and the FCA affirmed, all considerations point in the same direction [46].

The important principle emphasized by the FCA is that “Redrafting [the claims] would undermine the public notice function of patents, which entitles readers to clear and definite guidance concerning the extent of the monopoly conferred” [51]. If a construction favouring validity had to be adopted, then the claims could never be construed without a search to identify potentially invalidating prior art. It is reasonable to say that the patent should be construed in light of the common general knowledge which a skilled reader already possesses, but prior art for the purposes of anticipation, as was at issue in this case, is not necessarily part of the cgk.

More broadly, the statement that a patent should be construed to give protection to that which the inventor had actually invented was not intended as an overriding rule of law, but rather as a reminder that patents serve a public good in providing an incentive to invent, and consequently, “There is no occasion for being too astute or technical in the matter of objections to either title or specification” (Consolboard 520). But that is not to deny that obscure or poorly drafted patents can be a disservice to the public, regardless of the merits of the invention. While the inventive function of patents should not be ignored, neither should the notice function; the construction must be “reasonable and fair to both patentee and public” (ibid).

Barnes J’s costs award 2013 FC 1050 was also appealed. As described in my blog post, Barnes J awarded costs with a slight premium above Column IV of the tariff. The FCA affirmed. The main point of legal interest is that the FCA affirmed that its decision in Imperial Manufacturing 2015 FCA 100 sets out the appropriate standard for a review of a discretionary order, which is the same as the standard for a ruling of mixed fact and law [88]. On the facts, Barnes J's departure from the tariff was justified [90].

*It is somewhat confusing that the modern approach to claim construction is referred to as “purposive construction.” There is a distinction to be made between an overall "approach" to interpretation, and an analysis which may be part of that approach. So, the modern approach to statutory interpretation considers text, context and purpose, and seeks to arrive at a harmonious interpretation of the legislation in light of all three analyses. The portion of that analysis which looks to the purpose is referred to as the purposive analysis, while the approach as a whole is usually referred to simply as the “modern approach.” The approach to interpretation which would consider purpose of the statute as the overriding consideration, rather than merely one component, was referred to as a “purposive approach.” The modern approach to claim construction, like the modern approach to legislative interpretation, also considers text, context (in the form of the skilled readers cgk) and purpose. It is referred to as purposive interpretation because Catnic emphasized the need to consider purpose as a reaction to an excessive reliance on parsing the text. But Catnic never said the text should be ignored, and indeed the text of the claim itself remains of dominant important, just as the text of the legislation is the most important consideration in legislative interpretation. Thus “purposive construction” is not the same as a “purposive approach,” nor is it the same as a purposive analysis. It would be easier simpler if the current approach to claim construction were simply referred to as the “modern approach” to claim construction.