PATENTS |
Infringement |
Norac Systems International Inc. v. Prairie Systems and Equipment Ltd.
T-1973-95
2002 FCT 337, Pelletier J.
25/3/02
36 pp.
Plaintiff assignee of patent for mobile weighing system, designed to be used to accurately weigh loads carried on truck or trailer, often in non-level conditions--Defendant saying its system does not contain essential element of patent, therefore does not infringe patent--Defendant saying invention, as described in patent, lacking utility and inventiveness so that patent invalid--Defendant arguing finding of infringement could be avoided if defendant could be shown to be using different combination and arrangement of parts than did plaintiff--Doctrine of substantial infringement considered in Free World Trust v. Électro Santé Inc., [2000] 2 S.C.R. 1024 where Binnie J. concluded doctrine of substantial infringement could not be used to avoid consequences of language used in patent by inventor--Question of substantial infringement now question of essential and non-essential elements of claims--If substituted elements not essential, replacement by equivalent combination of parts matter of no consequence; infringement can still be found--However, in case of essential elements, their absence or substitution will lead to finding of no infringement--First task of judge dealing with patent claim to construe patent by applying principles of purposive construction: Whirlpool Corp. v. Camco Inc., [2000] 2 S.C.R. 1067--Since patent protecting means by which result obtained, rather than result itself, purposive construction should identify those functional elements which produce useful result in novel and inventive way--Action dismissed--No merit in allegation claims ambiguous-- However, weigh cell, as claimed in claims 6, 7, lacking utility; therefore claims invalid--Applying Beloit Canada Ltd. et al. v. Valmet Oy (1986), 8 C.P.R. (3d) 289 (F.C.A.) invention not anticipated by patents which precede "laid open" date and which were cited as prior art (Free World Trust)--As to obviousness, no evidence to find person skilled in art, employing common general knowledge of such persons, could have come to invention without employing imagination or intuition--Given presumption of validity, absence of evidence to contrary, no basis on which to conclude patent invalid for obviousness--As to infringement, finding that defendant substituted load cell for tension load cell--Substitution sufficient to avoid finding of infringement--Tension load cell essential element of claim--As essential element absent, no infringement herein--While, in hindsight, may not have been necessary to stipulate tension load cell when one also stipulated that output thereof must vary with tension load to which subject, inventor chose to specify tension load cell-- Consequently, requirement of tension load cell "troublesome or unnecessary limitation", self inflicted wound, effect of which that finding of infringement avoided by absence of tension load cell in defendant's device--Next issue in relation to infringement that of linkage system and nature of arrangement by which load cell able to maintain itself in vertical axis--It is this feature which contributes to inventiveness of device--Parties and experts misdirected themselves in considering meaning of coupling; "coupling" in patent herein not term of art; judge as well placed to interpret as experts--Coupling herein intended to convey functional relationship without necessarily conveying mechanical arrangement by which it is accomplished--In end result, patent invalid for lack of utility, but if valid, not infringed as lacking tension load cell and defendant's load cell not pivotally attached to linkage assembly--Nothing justifying solicitor and client costs.