1,292,693 / omeprazole formulation / LOSEC
As discussed here, Barnes J's decision at first instance, holding that AstraZeneca’s ‘693 patent to be valid and infringed, turned primarily on the facts. Unsurprisingly, the FCA has upheld Barnes J. The FCA decision is nonetheless interesting for its approach to claim construction, particularly in contrast with Locke J’s decision in Mediatube Corp v Bell Canada 2017 FC 6 (blogged here on the costs issue). That aspect of the decision is the focus of this post.
By way over overview, while Apotex raised a number of issues on appeal, the most important related to claim construction . On that issue, Apotex acknowledged that Barnes J had correctly stated the applicable principles, but argued that he had misapplied them . This argument was rejected by Gauthier J, essentially on the basis that it took passages from Barnes J’s decision out of context, and when read as a whole, it was evident that Barnes J had indeed applied the claim construction principles he had articulated (see eg ).
The FCA did vary Barnes J’s decision on a limitations period point, which was governed by s 39 of the Federal Courts Act, as this case was decided under the old Act . Section 39 provides that the provincial limitations period applies in respect of any cause of action arising entirely in one province, and a general six year period is otherwise applicable. The FCA held that on the facts, Barnes J had wrongly applied the six year period to all the infringing acts, even though some of them might have arisen entirely in one province . Rather than remanding, the FCA held that the difficult issue of assessing the limitation period applicable in respect of each act could be undertaken in the damages portion of this bifurcated trial . The legal error is of little significance going forward, as s 55.01 of the current Patent Act provides for a general six year limitation period, regardless of where the cause of action arose.
There is an ongoing debate in Canadian law as to whether recourse to the disclosure as an aid to construing the claims is always permissible, or is permissible only if the claims are ambiguous on their face. The latter position seems to stem from Procter & Gamble Co v Beecham Canada Ltd (1982) 61 CPR(2d) 1 (FCA) at 11, where the FCA reviewed the cases and summarized by saying:
in construing the claims in a patent recourse to the remainder of the specification is (a) permissible only to assist in understanding terms used in the claims; (b) unnecessary where the words of the claim are plain and unambiguous; and (c) improper to vary the scope or ambit of the claims.
(See also Dableh v. Ontario Hydro  3 FC 751 (FCA), repeating this.) Now, “unnecessary” does not mean “impermissible,” but in Mylan v Eli Lilly (CIALIS) 2016 FCA 119  the FCA took that next step and held that “the judge erred in referring to the specification when construing the claims of the ‘377 patent. The rules of patent construction preclude reference to the specification when the claims are clear, and improper if reference varies the scope of the claims” [sic] (my emphasis). On the other hand, in Whirlpool 2000 SCC 67 Binnie J, for the Court, said that:
"[t]erms must be read in context, and it is therefore unsafe in many instances to conclude that a term is plain and unambiguous without a careful review of the specification". In my view, it was perfectly permissible for the trial judge to look at the rest of the specification, including the drawing, to understand what was meant by the word “vane” in the claims, but not to enlarge or contract the scope of the claim as written and thus understood.
In his recent decision in Mediatube Corp v Bell Canada 2017 FC 6 Locke J had a very careful analysis of this “tension”  in the jurisprudence. On that point he quoted and agreed with Zinn J’s discussion in Janssen-Ortho 2010 FC 42, [115-116], , including this paragraph:
 In my view, the whole of the specification (including the disclosure and the claims) may be examined to ascertain the nature of the invention. Where the words of the claims are plain and unambiguous and capable of only one interpretation by a person skilled in the art, recourse to the disclosure is unnecessary. This is not to say that the interpreter should not examine the disclosure. In my view, one should do so, but with caution. Recourse may be had to the disclosure for the purpose of confirming the interpretation arrived at from examining the claims alone or to disclose an ambiguity in the language of the claims that was not otherwise evident. However, the patentee cannot expand the monopoly specifically expressed in the claims by borrowing phrases from the disclosure and placing them into the language of the claims.
This threads the needle between the two approaches, though rightly favouring the SCC position that reference to the disclosure is permissible even when the claims are unambiguous. Nonetheless, Locke J was very careful to first read the words of the claims alone to determine whether they were ambiguous. He did have recourse to the specification in interpreting each disputed terms, but in almost every case, this was only after expressly concluding the claim alone was ambiguous. See eg his discussion of “audio/video signals,” concluding examination of the claim alone “certainly gives rise to enough ambiguity in this term to justify recourse to the disclosure in order to assist in understanding its scope” . This implies that recourse to the disclosure, if not strictly impermissible, would not be “justified” absent the ambiguity. See similarly , , . (The only exception was in considering the term “server,” where he adverted to the disclosure without expressly holding the claim was ambiguous on its own ).
Contrast Locke J’s analysis with Gauthier J’s approach in this case:
 As the issue of construction of the patent is to be reviewed on the correctness standard, I have performed my own analysis of the 693 Patent. I have thus considered, as proposed by Apotex, what the invention is by reading the full specification.
The first sentence is explicit that Gauthier J is performing her own analysis, which means the approach she takes would be also appropriate for a judge at first instance. The second sentence indicates that Gauthier J very first step in construing the claims is to read the disclosure, without a word as to whether there is any ambiguity in the claims themselves. She also stated (my emphasis) that
 It is trite law that a court will consider the disclosure when it construes the claims. I considered the disclosure as it may help to determine if the inventor gave a particular meaning to an expression or word in the claim by adopting a special lexicon. However, the disclosure cannot be used “to enlarge or contract the scope of the claim as written and thus understood” (Whirlpool at para. 52 in fine; see also Justice Rothstein’s comment in the seminal decision of Apotex Inc. v. Sanofi-Synthelabo Canada Inc., 2008 SCC 61 at para. 77 in fine,  3 S.C.R. 265).
This was not merely a statement of principle; Gauthier J’s analysis of the claims at hand began with a twelve paragraph discussion of the disclosure -, before turning to the claims themselves.
The two approaches are not strictly inconsistent in principle, in that Locke J did acknowledge that it is permissible to look to the disclosure. Nonetheless, there is a striking contrast between Locke J’s claims-first approach and Gauthier J’s disclosure-first approach.
How can this tension be resolved? First, all of the cases agree on one fundamental principle: use of the disclosure is “improper to vary the scope or ambit of the claims,” and “improper if reference varies the scope of the claims”; “the patentee cannot expand the monopoly specifically expressed in the claims by borrowing phrases from the disclosure and placing them into the language of the claims”; “the disclosure cannot be used ‘to enlarge or contract the scope of the claim as written’”; and, from Sanofi  “Of course, it is not permissible to read the specification in order to construe the claims more narrowly or widely than the text will allow.” I am not aware of any case holding to the contrary.
In light of this principle, it is easy enough to see why recourse to the disclosure is unnecessary when the words of the claim are plain and unambiguous; it is unlikely to change anything. Even if reading the disclosure suggests a meaning that was inconsistent with the claims, the court would say, in effect, “I see what you should have said, but you didn’t say it, and I won’t redraft the claim for you.” If that’s right, whether one starts with the claims, or starts with the disclosure, should make no difference in the end. The point made by the SCC in Whirlpool is that there may be cases where the claims appear clear when read on their own, but the disclosure clarifies the true meaning. An example might be Catnic, where the word “vertical” in the claim might be taken to mean “90 degrees”, but reading the disclosure makes it apparent that it really means “sufficiently vertical to carry out the load bearing function.”* In that case, reading the disclosure changes our understanding of the claim, but does not read limitations from the disclosure into the claim. Rather the disclosure makes it apparent that the initial reading of the claim alone was wrong, because a word that appeared clear was in fact ambiguous. In such a case, it would be wrong to avoid recourse to the disclosure on the basis that the claims were unambiguous.
The really difficult case is when the claim says “up” and the disclosure defines “up” to mean “down.” I don’t have a ready answer for that case, except to say that would be a very poorly drafted patent. It would be better to address the such a case on its facts, in light of the underlying principles that claim defines the monopoly, but the skilled person reads the patent, rather than debating whether it is permissible or not to read the disclosure.
Finally, what about the statement in CIALIS that "[t]The rules of patent construction preclude reference to the specification when the claims are clear," and also "as there was no ambiguity in the claims here, there could be no recourse to the specification" ? I acknowledge that these statements of principle are inconsistent with a disclosure-first approach, but there is no inconsistency on the facts, because in CIALIS the real problem was that the trial judge had indeed read in a limitation from the disclosure into the claim: see . Thus the holding would have been the same on a disclosure-first approach.
*This oversimplifies Catnic, where the claim construction at trial was not merely “a purely literal one derived from applying to it the kind of meticulous verbal analysis,” as suggested by the HL.