Overbreadth Argument Rejected as Being Akin to the Promise Doctrine

Eli Lilly Canada Inc v Apotex Inc 2020 FC 814 St-Louis J

2,492,540 / tadalafil / CIALIS ADCIRCA

In this case, Lilly asserted that the processes used by Apotex to make tadalafil infringed Lilly’s 540 process patent. In addition to non-infringement, Apotex argued that the 540 patent was invalid for anticipation, obviousness, lack of utility and overbreadth. St-Louis J held that while the 540 patent would be infringed if it were valid, it was invalid for anticipation and obviousness, though the attacks based on lack of utility and overbreadth failed [204]. So far as I can tell, the holdings of invalidity on the basis of anticipation and obviousness turned on the facts and not on any point of law, though I have to say that the facts were quite complex and it is possible that I missed an issue.

There were a few other points of interest: (1) St-Louis J rejected an overbreadth attack as being akin to the promise doctrine; (2) there was a discussion of the presumption relating to process patents; and (3) there was a discussion of obvious errors in a claim, which related to the utility argument.

Overbreadth

Apotex argued that the 540 patent was overbroad on the basis that a particular (redacted) solvent has been tested and found not to work, but the disclosure nonetheless stated that it was useful [350].

St-Louis J rejected this argument, saying:

[356] The way that Apotex articulated the allegation of overbreadth in this case appears indeed very akin to the promise doctrine, abolished in AstraZeneca SCC. What Apotex really asks the Court to do is to parse the disclosure, conclude that [redacted solvent] promises to be useful for the PSR, import [redacted solvent] into Claim 1 in the absence of any ambiguity, and strike Claim 1 as a result.

She noted that the SCC in AstraZeneca SCC warned against this, and stated that “As such, the doctrine of overbreadth should not be applied in the manner suggested by Apotex, akin to the promise doctrine” [358].

St-Louis J’s comments strike me as entirely sound (with the caveat that her description of Apotex’s argument at [350] is very brief, so that can’t assess for myself her characterization of it at [356]). I have a paper on “Overbreadth in Canadian Patent Law” forthcoming in the IPJ, in which I argue that the approach to overbreadth adopted in Amfac (1986), 12 CPR (3d) 193 (FCA) “if widely adopted, risks invalidating patents for inventions which are new, useful and non-obvious, on the basis of an arbitrary parsing of the disclosure, in a manner reminiscent of the promise doctrine.” A draft version is available on SSRN (note that this draft was updated on 10 June from the first SSRN version). In that paper, I also show that overbreadth is almost always redundant, as merely restating a statutory ground of invalidity (most commonly lack of sound prediction of utility). In this case, if I understand Apotex’s argument correctly, it would appear that the preferable statutory basis for the attack would have been s 53(1); if St-Louis J had allowed the attack to go forward on the basis of overbreadth, this would have side-stepped the statutory requirements and related case law requiring wilfulness and materiality.

Presumption regarding a process patent

The 540 patent is a process patent, and Lilly argued that the burden should be reversed, so that Apotex would have to prove non-infringement on the basis of s 55.1, which provides that when the claim is to a process for obtaining a “new product” it should be presumed that the product was produced by the patented process. Lilly wished to argue that “new” meant that the product had not been sold on the market before, while Apotex argued it mean “new” in the sense of being previously known, whether or not it had received marketing authorization: [37], [38]. The prior caselaw at the FC level is against Lilly, which therefore did not press the point, but merely sought to preserve its rights on appeal [41].

Lilly also argued that the burden should be reversed on the basis of the common law rule that is more or less to the effect that “when the subject-matter of the allegation lies particularly within the knowledge of one of the parties, that party must prove it, whether it be an affirmative or negative character” [42]. The exact nature of the common law presumption is unsettled. In Cefaclor, 2009 FC 991, [221], Gauthier J held that the presumption would have applied “given the particular circumstances of this case,” if “Lilly had taken reasonable steps to obtain this information.” St-Louis J relied on this to hold that the presumption did not apply because the evidence did not allow her to conclude “that Apotex did not diligently seek to provide the requested process documents, nor that Lilly diligently sought further information from Apotex” [45]. This is reasonable enough as an application of Gauthier J’s holding to the facts of this case, though the caveat in Cefaclor regarding “the particular circumstances of this case,” suggests that the holding might be a fairly narrow one. It will be interesting to see how this line of reasoning develops in future cases.

Obvious Error in the Claim

Claim 12 had an obvious error. It read:

12. A method of preparing [tadalafi] comprising the steps of: . . .

(b) reacting [C] with [D] to provide [E];

            (c) reacting the product of step (b) with [F] and [G] to provide [E]; . . .

The product of step (b) is E, so reacting it with F and G would clearly not provide E. In fact, step (b) would not produce E, but rather a different compound, not otherwise mentioned in the claim [197]. The claim was otherwise correct, so that carrying out step (c) on the product of step (b) would indeed produce E.

It appears Apotex acknowledged that the error was obvious [343], and St-Louis J found on the facts that indeed a skilled person “would understand Claim 12 to bear [sic] a mistake, and would make tadalafil by following the sequence of actions” [349]. Nonetheless, Lilly did not ask the court to correct the error [197], [347]; instead “they are asking the Court to simply accept the evidence of the experts providing how a skilled person would read Claim 12c. Essentially, Lilly argue that the skilled person understands the error and accordingly understands the scope of the claim, which accords with the purposive approach construction” [197]; and see [347].

There is ample authority holding that an obvious error this type will not affect the construction of the claims: see eg Procter & Gamble (1979), 42 CPR (2d) 33, 36-37 (FCA); Cefaclor 2009 FC 991, [159]; Lovastatin 2010 FC 1265, [99]. Varco 2013 FC 750; Azithromycin 2005 FC 1421, [36]. The notion that the claim is not being “corrected” but merely read as a skilled person would read it is a technical distinction which is somewhat difficult to grasp.

In Procter & Gamble at 37 the FCA simply held that “the claims should be interpreted in the only way that makes sense”; in Cefaclor at [159] Gauthier J stated that a skilled person would “understand” the claim to apply as it should have been written; in Lovastatin at [99], Snider J held that the error “would not change the meaning ascribed to the phrase by the skilled addressee”; in Azithromycin at [36] Mosely J stated that the incorrect word in the claim is a typographical error “and is of no moment.” These statements are all a bit ambiguous as to whether the error was being “corrected” or rather that the claim was being read as a skilled person would read it. Phelan J in Varco at [336], on the other hand, expressly held that the error would be corrected: “[the plaintiff’s expert] opined that a Skilled Person would see the error and make the necessary corrections; and would not be confused or misled. [The defendant’s expert] all but admitted the same. Even a judge hearing this case could see the error and make the correction” (my emphasis).

In any event, a person untrained the law would say that an obvious error in the claim will be corrected. Even for a lawyer, that’s the easiest way to remember the rule. However one phrases it, the rule is very well established, with St-Louis J’s decision adding to the already ample authority.