Tuesday, November 29, 2011

The "Inventive Concept" and the Problem-and-Solution Approach to Obviousness

Allergan Inc v Sandoz Canada Inc / combigan (NOC) 2011 FC 1316 Crampton J

The Federal Court seems to be expanding the roster of judges assigned to patent cases, as we have had three decisions recently that appear to be the first patent decision for the judge in question: Rennie J’s anastrozole (NOC) decision, Scott J’s decision in Hollick Solar and now this decision from Crampton J. The fresh eyes have brought a new perspective on some old problems: Rennie J set out a structured framework for determining the promise of a patent; Scott J resurrected the Improver questions for determining whether an element is essential to a claim; and in this case Crampton J has addressed whether the claims or the inventive concept are the focus of the obviousness inquiry. While Crampton J resolved the question correctly, in my view, I suggest that the difficulty which arose in this case reflects a problem with the Windsurfing / Pozzoli test itself. This problem could be avoided, and the analysis simplified, by invoking the problem-and-solution approach that is standard in the European Patent Office.

COMBIGAN is Allergan’s brand name for a composition of two active ingredients, brimonidine and timolol, along with the preservative benzalkonium chloride, in specified proportions. COMBIGAN is indicated for reduction of intraocular pressure (IOP) associated with glaucoma. Sandoz sought an NOC to make a generic version. Allergan sought a prohibition order based on two listed patents:2,440,764, which covers the specific composition for the treatment of glaucoma; and 2,225,626 which covers a class of compounds including brimonidine for protecting the optic nerve against neurological damages (“neuroprotection”).

The sole allegation respecting the 764 patent was that it was invalid for obviousness. Various IOP lowering medications, including the two active ingredients in COMBIGAN, were commonly used in combination to provide the best IOP reduction, but this was normally done concomitantly, with a waiting period between the administration of the two drugs. The preservative benzalkonium was also commonly used in the prior art. The case therefore turned on an obvious-to-try analysis. A preliminary point arose at the second step of the Windsurfing / Pozzoli approach: “Identify the inventive concept of the claim in question or if that cannot readily be done, construe it” (Sanofi 2008 SCC 61 [67]). This implies that it is never really necessary to identify the inventive concept, since if any difficulty is encountered, it may be ignored. In Pozzoli itself Jacob LJ treated the inventive concept as a sometimes convenient but dispensable shortcut: he said that identification of the inventive concept “can develop into an unnecessary satellite debate” and in such cases “the sensible way to proceed is to forget it and simply to work on the features of the claim,” as “[i]n the end what matters is/are the difference(s) between what is claimed and the prior art” 2007 EWCA 588 at [19]. Similarly, in Actavis v Novartis [2010] EWCA Civ 82 at [20] Jacob LJ said that “[t]he ‘inventive concept’ can be a distraction or helpful. It is a distraction almost as soon as there is an argument as to what it is. It is helpful when the parties are agreed as to what it is.” But if this is so, why should the court ever bother to identify the inventive concept in the first place? After all, the general principle is that validity is to be determined on the basis of the claims as construed, without importing limitations from the disclosure.

Accordingly, in this case Sandoz argued that the inventive concept must be discerned solely from the claims [46]. This presumably would have made it easier to establish obviousness, as there was no inventiveness in the manufacturing the composition. Crampton J disagreed, saying that where the inventive concept is not readily discernable from the claims, it is both permissible and “necessary” to look to the specification as a whole [51]. This holding was based directly on Sanofi at [77], but Crampton J sharpened the point by saying it was “necessary” where the SCC in Sanofi had used the word “acceptable.” Consequently, Crampton J held that the inventive concept included the various advantages of the claimed composition over the prior art, and the question was whether those advantages were obvious.

In my view Crampton J was undoubtedly correct on this point. The reason is that “[p]atents are essentially about information as to what to make or do.” (Aerotel Ltd v Telco Holdings Ltd [2006] EWCA Civ 1371, Jacob LJ [32]) Similarly, as Lord Hoffmann said in Biogen Inc. v. Medeva Plc [14], “[w]henever anything inventive is done for the first time it is the result of the addition of a new idea to the existing stock of knowledge.” The quid pro quo for a patent is not the thing claimed, but the information disclosed in the specification: Consolboard Inc. v. MacMillan Bloedel (Sask.) Ltd., [1981] 1 SCR 504, 517. So for example, claims to a pharmaceutical in combination with a particular pharmaceutically acceptable salt may be structured identically in two different patents, but it may be that in one case the inventive concept is that the pharmaceutical itself is useful for treating a certain condition, while in other it is that the combination of the particular salt and the particular pharmaceutical has superior manufacturing properties. The obviousness analysis must be conducted very differently in the two cases. As another example, failure to identify the inventive concept in a combination patent may result in an erroneous focus on individual elements: see Rockwater Ltd v Technip France SA & Anor [2004] EWCA Civ 381 esp. [125-28] rev'g [2003] EWHC 812 (Ch), in which the Court of Appeal criticized Laddie J. on this ground. A further example, provided by the Supreme Court in Sanofi at [77], is that of a chemical compound. If the compound itself is new, it may be claimed per se, but the compound must have some use in order for the claim to be valid. An arbitrary compound cannot be claimed; is it the information that the compound is useful for some purpose that supports the validity of the patent: Sanofi SCC [77]. Note that in Pozzoli Jacob LJ remarked at [20] that a chemical class claim is an example where “it is not even practical to try to identify a concept.” The contrary position of the Supreme Court in Sanofi, that this is an example where it is not only practical, but necessary to identify a concept, is more persuasive.

The real question is why the courts would ever simply construe the claim rather than identify the inventive concept. The answer is that identification of the inventive concept can be an uncertain task. There is no generally accepted approach to identification of the inventive concept in Canadian law. Consequently, the concept seems nebulous and akin to looking to the "spirit of the invention," which was so roundly disparaged by the Supreme Court in Free World Trust 2000 SCC 66. It is no wonder that is it standard for Canadian courts to undertake the obviousness analysis by construing the claims rather than identifying the inventive concept.

I suggest that the notion of the “inventive concept” is not inherently ill-defined or uncertain; it is the “add[ition] to the cumulative wisdom” that warrants the grant of the patent, in contrast to the invention as claimed, which is the practical application of that knowledge: Shell Oil [1982] 2 SCR 536, at 549, quoted by Crampton J at [80]. The problem is that there is no well-established method for determining what the inventive concept is in any given case. The analysis is typically ad hoc, as it was both in Windsurfing and in Sanofi. The SCC in Sanofi, for example, simply asserted at [78] that the inventive concept was “apparent.”

The problem-and-solution approach used in the EPO in effect provides a way of determining the inventive concept. Rather than asking whether the invention was obvious in light of the prior art, the problem-and-solution approach asks what problem was faced in the prior art, and then asks whether the solution provided by the patent was obvious. In effect the patent’s solution to the problem plays the same role as the inventive concept in the Pozzoli approach; indeed, I would argue that the patent’s solution to the problem is the inventive concept of the claim. In other words, the problem-and-solution approach provides a structured method of identifying the inventive concept.

In the COMBIGAN case it was relatively uncontroversial that the problem in the prior art was to find a composition that could replace concomitant treatment, as this would provide better compliance and reduced exposure to preservatives [45]. If the patent’s inventive concept is understood as the solution to this problem, then it necessarily includes the properties of the composition that make it advantageous for that purpose. Thus the problem-and-solution analysis provides a structured approach which leads directly to the same result as was arrived at by Crampton J.

This may seem like a radical suggestion, but it is not. The Patent Rules s 80(1)(d) require a statement of the technical problem and its solution, and it has long been routine for Canadian and English courts to orient the obviousness inquiry by reference to the problem addressed and the solution provided by the patent: see eg Vickers v Siddell (1890) 15 App Cas 496, 500 (HL); General Tire v Firestone Tire & Rubber [1972] RPC 457, 475-476 (CA); Canada v. Uhlemann Optical Co. [1952] 1 SCR 143, 152; Northern Electric Co. v. Brown's Theatres Ltd.[1940] ExCR 36, (1940), 1 CPR 180 at 185, affirmed [1941] SCR 224. Lord Hoffmann in Biogen Inc v. Medeva Plc [1996] UKHL 18, [53] has gone so far as to say that “[a] proper statement of the inventive concept needs to include some express or implied reference to the problem which it required invention to overcome.” The Federal Court is increasingly likely to expressly identify the problem addressed by the patent and the solution it provides as a necessary part of part of the validity inquiry: see eg AstraZeneca Canada Inc. v. Apotex Inc. / esomeprazole (NOC) 2010 FC 714, [33]; Jay-Lor International Inc. v. Penta Farm Systems Ltd. 2007 FC 358, [9]; Pfizer Canada Inc v Apotex Inc / sildenafil (NOC) 2007 FC 971, [57] aff'd 2009 FCA 8, [11]. The problem-and-solution approach is not universally applicable; it not appropriate when the inventive step lies in the very recognition of a problem, for example. But when identifying the inventive concept because a problem, the problem-and-solution approach may provide a solution.

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