we wrote about a trilogy of Federal Court decisions relating to
Eli Lilly's erectile dysfunction (ED) drug CIALIS®
(tadalafil). While Lilly was successful in obtaining a prohibition
order in the first proceeding, its latter two applications were
dismissed. Mylan appealed the first order, and the Federal Court of
Appeal (FCA) recently released its decision in Mylan
Pharmaceuticals ULC v. Eli Lilly Canada Inc., 2016 FCA 119 dismissing Mylan's
The FCA's decision affirms the view that obviousness and
obviousness-type double patenting validity challenges require
distinct analyses, and that a patent's disclosure cannot be
referenced to vary the scope or ambit of its claims where those
claims are unambiguous.
In the hearing below, Mylan alleged that Lilly's '784
Patent was invalid on the basis of, among other grounds,
obviousness-type double patenting over Lilly's earlier '377
Patent. The earlier patent claimed the compound tadalafil, while
the later patent claimed tadalafil for the treatment of ED.
In the decision below, Justice de Montigny construed the claims
of the earlier patent in light of the patent as a whole to conclude
that it claimed tadalafil as a PDE V inhibitor, but did not claim
or contemplate its use for the treatment of ED. He held that
Mylan's allegation of obviousness-type double patenting was
unjustified, as Lilly's '784 Patent was patentably distinct
from the earlier patent:
Although both are claims for the same chemical compound,
tadalafil, they are claims for different uses of this compound. The
'377 Patent does not contemplate the use of tadalafil to treat
ED; rather, this is precisely the monopoly claimed in the '784
Patent. As Lilly notes, when the '377 Patent expires, the
public will be free to use tadalafil for the uses claimed in the
'377 Patent. Therefore, the claims are patentably distinct.
On appeal, the FCA distinguished obviousness-type double
patenting from obviousness. According to the FCA, obviousness asks
whether a legal "invention" exists in light of all of the
relevant prior art. By contrast, obviousness-type double patenting
asks whether there is an inventive step from an earlier patent to a
later one. The focus is whether the second patent contains an
inventive element beyond that claimed in the first which makes it
In the present case, the FCA held that Lilly's earlier
'377 Patent claimed tadalafil, but its status as a PDE V
inhibitor was evidenced only by the disclosure of the patent, not
by its claims. The FCA held that Justice de Montigny erred by
interpreting the '377 Patent as claiming tadalafil
as a PDE V inhibitor, because its status
as such was only made clear in the disclosure of the patent, not
In my view, 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. [...]
To conclude, as there was no ambiguity in the claims here, there
could be no recourse to the specification.
However, the FCA acknowledge that the effect of the trial
judge's construction was to impose a higher burden on Lilly in
terms of overcoming the obviousness-type double patenting
allegation; by focusing on the functionality of the compound
claimed in the earlier patent, the inventive "gap"
between the two patents was effectively narrowed. As such, while
the FCA held that Justice de Montigny erred in his construction,
his conclusion that the '784 Patent was patentably distinct was
The FCA's decision calls into question the relevance of a
patent's disclosure when it comes to understanding a
patent's claims where those claims are not ambiguous. While it
is well-established that a patent's disclosure cannot be
referenced to vary the scope or ambit of its claims, the Supreme
Court of Canada has cautioned that claim terms must be read in
context, and that it is unsafe to conclude that a term is plain and
unambiguous without a careful review of the patent as a whole. In
Whirlpool Corp. v. Camco Inc., 2000 SCC 67, Justice Binnie noted that
"it was perfectly permissible for the trial judge to look at
the rest of the specification, including the drawing, to understand
what was meant [...] in the claims, but not to enlarge or contract
the scope of the claim as written and thus understood".
It will be interesting to watch how this most recent
pronouncement from the FCA on patent claims construction will be
interpreted in future decisions.
The Federal Court dismissed a motion by Apotex seeking particulars from Allergan's pleading relating to the prior art, inventive concept, promised utility and sound prediction of utility of the patents at issue.
Last year we saw the Canadian Courts release trademark decisions that granted a rare interlocutory injunction, issued jailed sentences for failure to comply with injunctive relief, grappled with trademark and internet issues...
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