Is the Best Mode Requirement Restricted to Machines?

Western Oilfield Equipment Rentals Ltd v M-I LLC 2021 FCA 24 Locke JA: Gleason, Mactavish JJA affg 2019 FC 1606 O'Reilly J

            2,664,173 / Shaker and Degasser Combination

Previous posts have provided some background on this case and addressed reasonable compensation and the Gillette defence. Locke JA also made two noteworthy points with respect to the best-mode requirement set out in s 27(3)(c), which requires that the specification must “in the case of a machine,” explain the best mode of practising the invention. As discussed here, O’Reilly J had dismissed this argument on the basis that it “relates solely to machines and, as I understand the patent, it claims a method and a system, not a machine” [FC 146], [118]. Locke JA remarked that the mere fact that the claim at issue was phrased as being to “a system” did not in itself establish that it is not to a machine [119]. This makes sense to me; the question of whether the claim is to a machine should be a matter of the substance of the claim and not its form.

More importantly, Locke JA stated that “there is considerable doubt as to whether, despite the wording of paragraph 27(3)(c), the best-mode requirement is limited to machines,” citing various commentators [119]. This is interesting given that the FCA in Pfizer v. Novopharm / sildenafil (NOC) 2010 FCA 242 [72] approved Snider J’s holding in Ramipril FC 2009 FC 676 [329] that “the ‘best mode’ obligation only arises in the case of a patent to a machine.” I must say that Snider J’s textual analysis strikes me as fairly compelling, but far be it for me to dissuade the FCA from relying on commentators. Locke JA’s observation was expressly obiter, and the point made no difference to the outcome, but nonetheless the point can no longer be considered settled.

What Is a “Machine”?

Western Oilfield Equipment Rentals Ltd v M-I LLC 2019 FC 1606 O'Reilly J
            2,664,173 / Shaker and Degasser Combination

A previous post described the facts and some miscellaneous legal points raised by Western Oilfield Eqpt v M-I. This post consider the best mode requirement, and in particular the question of what it means for an invention to be “a machine.”

Best Mode
O'Reilly J rejected Western’s insufficiency arguments on the basis that all of the putative defects in the disclosure were within the ability of a skilled person to address without inventive ingenuity: [141]-[144].

He also summarily rejected an attack based on failure to disclose the best mode, per s 27(3)(c), on the ground that:

that provision relates solely to machines and, as I understand the patent, it claims a method and a system, not a machine [146].

That the provision relates solely to machines is well established. It is clear on the face of the provision, which applies “in the case of a machine,” and has been confirmed in a few cases: see 2009 FC 676 [328-33]; 2010 FCA 242 [72-73]; 2014 FC 844. But what is a “machine”? To my knowledge, the question did not arise in the prior cases, all of which concerned a composition of matter (to use the statutory term), namely ramipril, sildenafil and polyethylene copolymers, which are clearly not machines.

It seems clear enough that a method is not a machine, but what about a system? The mere fact that the claim uses the word “system” cannot be enough to settle the point, or it would be easy to avoid application of the provision by appropriate wording. Indeed, most claims to what would normally be considered a machine do not use that term, but rather claim eg “a vertical feed mixer.”

On the facts, Claim 19 was as follows:

19. A system comprising:

a first screen having an upper side and a lower side for separating drill cuttings and

drilling fluid within a shaker; and

a pressure differential generator configured to pull air or vapor through the first screen to enhance the flow of drilling fluid through the first screen with respect to a second screen within the shaker in which the pressure differential generator does not create a pressure differential between an area above and an area below the second screen

It’s not entirely clear to me that this does not describe a machine. That is not to say that I disagree with O’Reilly J’s conclusion, but only that there is a puzzle. Screens and a vacuum pump are fairly ordinary components of a machine. Perhaps it is a system rather than a machine because the shaker itself is a machine, and the invention additionally comprises drilling fluid, which is not part of the shaker? While that seems reasonable enough, it is not particularly compelling, and it would desirable to have this interpretation buttressed by purposive considerations.

Turning to the Act, s 2 defines an “invention” to mean any new and useful “art, process, machine, manufacture or composition of matter.” The question then is whether the “system” at issue should be considered a “machine” rather than an “art” or perhaps a “composition of matter.” The answer does not seem clear as a matter of ordinary language. Unfortunately, purposive considerations do not help much in interpreting the provision, as there is no obvious policy for confining the best mode to machines (even though the text clearly does so). It seems this provision, introduced in the Patent Act, 1935 s 35, was modeled on the US Patent Act in effect at the time, which was similarly restricted to a machine, but the US Act has subsequently been amended to provide for a broader best mode requirement which is generally applicable. This makes it difficult to invoke purposive considerations in drawing the distinction between a “machine” and any other type of invention.

I’m inclined to think that confining the best mode requirement to machines is arbitrary. It would be better to either expand it to encompass all types of inventions, as was done in the US Act, or (preferably) eliminate it entirely. Until there is some clear purposive rationale for confining the best mode requirement to “machines,” the scope of the provision will necessarily be uncertain, and a restrictive approach to the interpretation of the provision, such as that applied by O'Reilly J, is probably the best approach, as it has the virtue of minimizing uncertainty. It would be very unfortunate if an expansive yet unclear definition of “machine” became a trap for unwary drafters.

Another Application of the Duty to Disclose the Invention

Pfizer Canada Inc v Apotex Inc / celecoxib (NOC) 2014 FC 314 Harrington J
            2,177,576 / celecoxib / CELEBREX

I blogged yesterday about the promise of the patent in Apotex / celecoxib. This post concerns the second main issue, which is the duty to disclose the invention. There are several points of interest, though none represent major legal developments.

Apotex made three submissions regarding sufficiency of disclosure [43]:

(1) that one individually claimed compounds (Claim 5) was toxic and therefore useless;

(2) Claim 16, to the compounds for use in the prevention of colorectal cancer is unfounded; and

(3) Pfizer failed to disclose that the true invention was celecoxib, (Claim 4) with respect to which Pfizer had already formed the intention to seek regulatory approval.

Taking the second point first, Pfizer effectively conceded, for the purposes of this application, that the compounds were not useful for treating colorectal cancer [46]. But Pfizer has only to establish that one valid claim is infringed in order to obtain an order of prohibition [45], and so Pfizer accordingly argued that the validity of Claim 16 was not determinative of the application, because s 58 provides that claims stand or fall independently. Apotex responded by arguing that the utility of the invention, which is found in the disclosure, is inherent in every claim, and if Claim 16 is invalid, the entire patent falls. Apotex’ argument is set out only summarily by Harrington J, but it is presumably based on on the SCC Teva / Sildenafil 2012 SCC 60, in which a claim to a useful compound was struck down because other claimed compounds lacked utility. I can’t speculate on how exactly Apotex felt that Sildenafil applied to the facts at hand, but in my article The Duty to Disclose “The Invention”: The Wrong Tool for the Job, (2013) 25 IPJ 269, I did argue that the Sildenafil decision eviscerates s 58. Harrington J rejected Apotex’ allegation on this point, holding simply that the submission “is not in accord with s. 58 of the Patent Act and the decision of the Supreme Court in Teva (Sildenafil/Viagra)” [47]. While Harrington J did not elaborate further on the relationship between Sildenafil and s 58, it is clear that he views the two as consistent. While this is contrary to the argument I made in my article, I am nonetheless very pleased by this holding, because I felt that the SCC was wrong to undermine s 58. I said in my article that “I hope that I have misunderstood the court’s holding; I have certainly not found it easy to interpret.” Harrington J’s holding on this point, while not fully reasoned, is a welcome indication that I was indeed wrong in my interpretation of Sildenafil.

The first point, regarding the utility of Claim 5, similarly appears to be relevant only because of its effect on Claim 4, and would also be susceptible to being answered by s 58. But Harrington J addressed the point more directly, holding that

[44] The fact that tests had revealed high doses of the compound in Claim 5 were toxic in rats does not detract from the fact that Claim 5 works as an anti-inflammatory. There was no promise it would receive regulatory approval.

There is a certain tension here with the SCC statement in Tennessee Eastman [1974] SCR 111 that

There is no doubt that when a new substance is claimed as an invention of a "medicine", it has to be shown that it is active and nontoxic in therepeutic doses. Otherwise the patent fails for lack of utility and this is so if a class of substances is claimed some of which are useful as a "medicine", some of which are not.

We might distinguish this on the basis that Tennessee Eastman refers to “therepeutic” [sic] doses, while in this case the toxicity was revealed at “high” doses. However, I think it is more realistic to say that Harrington J’s holding relfected the point made that in Cameron ed Canadian Patent Law Benchbook at §4.8.1.2 that “some care must be exercised in the application of [the Tennessee Eastman] principle].” Apotex Inc / celecoxib should be added to the several cases cited therein as illustrating the conservative interpretation the courts have given to that principle.

I would note also that the view that the claimed compound must be nontoxic in therepeutic doses was obiter in Tennessee Eastman, and it was also obiter in Ciba v Commissioner of Patents [1959] SCR 378, which was relied on in Tennessee Eastman. Ciba in turn cited the decision of Jekins J in Re May & Baker Ltd (1948) 65 RPC 255 (Ch). In May & Baker there was no evidence at all of any utility for the substantial majority of the compounds of the claimed class (p287), which is quite different from a situation, as in this case, where the compounds clearly have a therapeutic effect, and the question is whether side effects would make them not clinically useful in practice. With that said, Jenkins J’s opinion does have statements which might suggest that therapeutic utility in humans, including lack of toxicity, is necessary to support a patent (see esp p 284); but such a suggestion is inconsistent with the holding in Wellcome / AZT 2002 SCC 77 [3] that regulatory approval is not the measure of patentable utility. I note also that the invention at issue in May & Baker was effectively a type of selection invention (p 282-83), so that the claimed compounds had to exhibit some advantage or lack of disadvantage as compared with the prior art compound, which was therapeutically useful, and this may justify the requirement for therapeutic utility on the particular facts.

The third point gets to the heart of the Teva / sildenafil duty to disclose the invention. Apotex argued that Pfizer failed to disclose that the true invention was celecoxib, with respect to which it had already formed the intention to seek regulatory approval [43]. Harrington J readily distinguished Teva / sildenafil from the facts at hand; in the SCC case, the utility of the individually claimed compounds, other than sildenafil itself, had not been established, whereas in this case the utility of all three of the individually claimed compounds was established [59]. Consequently, “[t]he true invention was the class of compounds” [59]. This distinction is, in my view, entirely sound. It is quite similar to, and consistent with, Snider J’s holding in Teva / imatinib 2013 FC 141 (blog). A more difficult question would have arisen had Harrington J come to the opposite conclusion with respect to the compound of Claim 5, so that it could not be said that the true invention was the whole class. In my view, that scenario is where there is a tension between s 58 and Teva / sildenafil. But given Harrington J’s holding that Claim 5 was valid, that tension will have to be resolved on another day.

One point of general importance is that “[t]here was no obligation upon Searle at the time the patent was filed to disclose therein its hope to commercialize Claim 4" [60]. This implies that “the invention” is determined by patentability criteria, and not by business intent. In my view, this holding is entirely consistent with both the Act and Teva / sildenafil.

Finally, Harrington J [50]-[52] also applied the FCA’s direction in Pfizer v. Novopharm / sildenafil (NOC) 2010 FCA 242 [72], to hold that the best mode requirement applies only to machines, notwithstanding Thorson P in Minerals Separation [1947] Ex CR 306, 12 CPR 102, that “the inventor must act uberrima fide and give all information known to him that will enable the invention to be carried out to its best effect as contemplated by him.” While Harrington J was bound to apply the law as set out by the FCA, in a recent article, Best Mode Disclosure in Canadian Patents 25 IPJ 303 (2013), Professor Vaver has argued that on the contrary, the express inclusion of a best mode duty for machines does not impliedly exclude the same duty for all inventions.

First Application of the Sildenafil Disclosure Requirement

Teva Canada Ltd v Novartis AG / imatinib 2013 FC 141, Snider J

            GLEEVEC / imatinib mesylate / 2,093,203

Snider J’s Imatinib decision, at [336-387], is the first to apply the disclosure requirement since the SCC released Sildenafil 2012 SCC 60. Snider J has done an admirable job in applying a difficult doctrine, and she has clarified some important points. But the Imatinib decision also illustrates some difficulties that arise from unresolved ambiguities in Sildenafil itself.