Source: http://www.sufficientdescription.com/2011/03/claim-construction-and-validity.html
Timestamp: 2019-04-23 10:51:23+00:00

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Thus the true rule is that the claims should be construed with a view to validly claiming that which the inventor has invented and disclosed. This follows from the general rule that legal documents, from legislation, to patents, to contracts, are to be of construed in light of the drafter’s purpose. The skilled reader does not just understand the technical terms that are used in the patent; she also understands the technical advance made by the patentee, and she understands that the patentee intends to claim that advance. For a more extended discussion, see my recent article, “The Essential Elements Doctrine in Patent Infringement: Free World and Whirlpool in Light of Kirin-Amgen” 22 IPJ 223 - 251 (2010).
With that said, I have been unfair to Gauthier J in taking her statement out of context. Phostech was arguing for a construction that would have rendered the claim invalid, and in saying that the Court must construe the claim “without regard to its validity,” Gauthier J was saying in effect that the Court should not go out of its way to construe the claim in a manner that will result in invalidity. This is entirely consistent with the authorities cited above.
Footnotes are after the break.
1 Western Electric Co. v. Baldwin International Radio of Canada,  S.C.R. 570 at 574,  4 D.L.R. 129, quoted by the SCC in Consolboard, supra note 58 at 521, in Whirlpool, supra note 1 at para. 49(g), and in Free World, supra note 2 at para. 43; Monsanto Canada Inc. v. Schmeiser, 2004 SCC 34,  1 S.C.R. 902 (referring to this as “the guiding principle” at para. 35).
2 Hinks & Son v. Safety Lighting Company (1876), 4 Ch. D. 607 at 612, Sir George Jessel, quoted with approval in French's Complex Ore Reduction Co. of Canada v. Electrolytic Zinc Process Co.,  S.C.R. 462 at 470,  4 D.L.R. 902; Noranda Mines Ltd. v. Minerals Separation North American Corp.,  S.C.R. 36 at 65, 12 C.P.R. 99; Consolboard, ibid.; Apotex Inc. v. Wellcome Foundation Ltd., 2002 SCC 77 at para. 92,  4 S.C.R. 153; Harvard College v. Canada (Commissioner of Patents), 2002 SCC 76 at para. 59,  4 S.C.R. 45, Binnie J., dissenting.
3 Haworth v. Hardcastle (1834), 131 E. R. 1087 at 1091, 1 Web. Pat. Cas. 480 at 485.
4 Rockwater Ltd. v. Technip France SA,  EWCA Civ 381 at para. 41,  R.P.C. 919, [Rockwater], Jacob L.J. quoting with approval para. 28 of his decision in Tickner v. Honda,  EWHC (Pat) 8 [Tickner].
Just FYI, the observation of Jacob LJ that you quote (your reference #4) was disapproved by the House of Lords in Kirin Amgen  UKHL 46 at .
On the other hand, English authority supports the idea that the patenteee is to be regarded intending to claim something which they regard as inventive - e.g. Virgin Airways  EWCA Civ 1062.
Yes, I realize that comment was disapproved. My article that I mention in the post, “Free World and Whirlpool in Light of Kirin-Amgen” is essentially an extended argument that Lord Hoffmann’s decision in Kirin-Amgen was entirely wrong-headed on claim construction. I argue that it was the very antithesis of a purposive construction. On the particular point regarding the presumption of validity, Lord Hoffmann said “There is no presumption about the width of the claims. A patent may, for one reason or another, claim less than it teaches or enables.” That is quite true, but it does not follow that there is no presumption; a presumption can always be overcome. As Jacob LJ pointed out in response to Lord Hoffmann, “[t]rue it is that ‘a patent may, for one reason or another, claim less than it teaches or enables’ . . .but that is not a reason for interpreting the claim in the context of the patent in a way that no rational patentee would have intended.” Ranbaxy v. Warner-Lambert,  EWCA Civ 876 at . My view is that Jacob LJ had the better of that debate.
One possible way to reconcile the various threads might be to distinguish (a) what the patentee thought was inventive (based on what they said in the description) and (b) what is actually inventive over the prior art in the court's opinion. Then one can say that the claim should be interpreted to cover (a) - no more, no less; but that (b) is irrelevant to claim construction. Just a thought.

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