The decision is interesting in that the Supreme Court took the step of finding the patent invalid, rather than simply allowing the Canadian Minister of Health to grant the notice of compliance, said Sean Jackson of IP Osgoode.

It has also clarified the Canadian disclosure requirement. “Sufficiency of disclosure lies at the very heart of the patent system, so adequate disclosure in the specification is a precondition for the granting of a patent,” said the judgment. In this respect, the Court found Pfizer’s patent lacking. The panel explained: “Although the patent includes the statement that ‘one of the especially preferred compounds induces penile erection in impotent males’, the patent application does not disclose that the compound that works is sildenafil, that it is found in Claim 7, or that the remaining compounds had not been found to be effective in treating ED.”
Pfizer’s patent was due to expire in 2014. Teva said its generic version of the drug will “result in millions in savings to consumers”.