Astra's esomeprazole patent was found invalid for inutility in any event because certain promises were not made out even with confidential inhouse tests (paras. 214, 215, 367). (slaw.ca)
It is rooted in a 1981 decision of the Supreme Court of Canada, Consolboard Inc v. MacMillan Bloedel (Sask) Ltd, in which the Court defined patent inutility as meaning «that the invention will not work, either in the sense that it will not operate at all or, more broadly, that it will not do what the specification promises that it will do.» (canadianlawyermag.com)
There is a risk of inutility where a patentee provides extensive detail to the court regarding the actual work it has conducted, to show the patentees in fact had a «secret» sound prediction. (slaw.ca)