Is the Law of Collocation Separate from Obviousness?

Eli Lilly Canada Inc v Apotex Inc 2018 FC 736 Manson J
            2,432,644 / prasugrel / EFFIENT / NOC

The claims at issue in this NOC application were to the combination of prasugrel and aspirin for treating blood clots [5], [13], [65], [66]. Manson J held the claims to be obvious, while rejecting attacks based on patentable subject matter, sufficiency and overbreadth. The obviousness holding turned on the facts, but the “subject matter” attack is of some general interest.

Prasugrel is a member of class of compounds known as “thienopyridines” which also includes ticlopidine and clopidogrel, all of which were known to have antiplatelet aggregation activity [11], [49]. Aspirin is well-known compound, which was also known to have antiplatelet activity, though it is not a thienopyridine. Ticlopidine and clopidogrel had previously been combined with aspirin to treat blood clots: Ticlopidine with aspirin was a standard antiplatelet therapy after stent implantation, and clopidogrel with aspirin had been shown to be even better, and was widely used [108], [117]. It was also known that clopidogrel with aspirin, at least, had synergistic effects [116]. The question was whether this made it obvious to try the new member of the class, prasugrel, in combination with aspirin for the same purpose. Manson J held on the facts that it was self-evident to try the combination, and that there was a reasonable expectation of success. The claims at issue were therefore invalid for obviousness [115], [121], [122].

What was referred to as the “subject matter” argument turned on the proposition that “it is essential to the validity of a patent for a combination that the combination should lead to a unitary result, and that such result should be different from the sum of the results of the elements,” [72], citing R v American Optical Co (1950), 13 CPR 87 at 98-99 (Ex CR). On the facts, this question turned into a debate as to whether the effect of the combination was additive or synergistic. The point of more interest is whether such a requirement is sound, at least as distinct from the requirement of obviousness. Certainly, there is ample support for the proposition. American Optical held that

It is essential to the validity of a patent for a combination invention, apart from considerations of novelty and inventive ingenuity that the combination should lead to a unitary result rather than a succession of results, that such result should be different from the sum of the results of the elements and that it should be simple and not complex. The elements may interact with one another provided they combine for a unitary and simple result that is not attributable to any of the elements but flows from the combination itself and would not be possible without it.

Essentially the same proposition has been recently affirmed by the House of Lords in Sabaf SpA v MFI Furniture Centres Ltd, [2004] UKHL 45, [24], [26]. The body of law to the effect that there is a distinct requirement of this type for a combination to be patentable is sometimes referred to as the “law of collocation.”

I must say that I find the EWCA decision in Sabaf [2002] EWCA Civ 976, [43], which held that “there is no separate law of collocation,” to be more persuasive, even though it was disapproved by the House of Lords on this point. In a seminal passage on the patentability of combinations, Green LJ in Albert Wood & Amcolite Ltd v Gowshall Ltd (1936), 54 RPC 37, 40 (CA) stated that “The real and ultimate question is: Is the combination obvious or not?” This passage has often been cited with approval by the Canadian courts, including the SCC in Wandscheer v Sicard Ltd, [1948] SCR 1, 12, and many times since. If the obviousness of the combination is truly the real and ultimate question, it is difficult to see how there can be a separate rule against collocation. As the Court of Appeal pointed out in Sabaf, [43]-[44], it is well accepted that “the act of combining known concepts may itself involve an inventive step,” but if there is a separate and prior step of determining whether the claimed invention is a true combination or a mere aggregation, a court may conclude that the claim is invalid without even considering whether it is obvious, thereby bypassing the real question. To the extent that the collocation analysis is a short-cut to the obviousness inquiry, it is a dangerous short-cut. Of course, it might be that Green LJ was wrong, and the real question is not simply whether the combination was obvious. But to my mind, neither Sabaf nor American Optical provides an adequate justification for a distinct requirement that has the effect that a combination that is new, useful and non-obvious invention should nonetheless be held to be invalid. The HL in Sabaf asserted that if there is no interaction or synergy, then the separate parts of the combination are separate inventions, and the obviousness inquiry should therefore be applied to each part separately. But I cannot see how this is consistent with the principle that a combination of known parts may be an invention if it would not have been obvious to combine them. Green LJ’s statement that the real question is the obviousness of the combination, was intended precisely as a warning against the danger of a “dissection of a combination into its constituent elements and the examination of each element in order to see whether its use was obvious or not.” As he pointed out, it is “the obviousness or otherwise of each act of selection” that is at issue in a combination invention, and not the obviousness of the individual components. To my mind, Sabaf does not respond adequately to Green LJ’s point.

In any event, the point is moot in the context of this particular case, as Manson J concluded that the 644 patent did disclose an effect that is “more than the mere sum of the effects of the two agents taken alone” [90].