Whirlpool Corp. v. Camco Inc.
T-2028-95
Cullen J.
18/8/97
57 pp.
At issue patents for different embodiments, improvements on dual action agitator for clothes washing machines-Plaintiffs alleging in 1995, on expiry of its U.S. dual action agitator patents, defendants launching new agitator copying plaintiffs' agitator-Introducing agitators, washers without licence or consent of plaintiffs while patent '803 still in force in Canada-Necessary to (i) construe patent to discern what invention disclosed by it actually is; (ii) determine validity, bearing in mind statutory presumption of validity of patent, thus imposing certain onus on defendants to disprove validity; (iii) address question of infringement-(1)(i) Whether "removability" of upper auger invention in '803 patent-Court looking at claims first when construing patent-Title of patent insufficient indicator of essence of patent-Claims describing two-part agitator with one-way clutch located between two parts-Plain, unambiguous-"Removability" feature, advantage, but not essence, of invention-Intention of inventor revealing substance of invention-Intention gleaned by reading patent as whole, bearing in mind claims first, foremost defining invention-Unclear whether invention intended to be merely removable upper auger accessory for agitator, or entire agitator consisting of removable upper auger accessory plus lower oscillating agitator, attachments-Where more than one construction may reasonably be reached, Court should favour one upholding patent-Summary of Invention as set out in patent clearly, unequivocally defining invention of '803 patent as unique drive mechanism connecting lower agitator to upper auger in absence of drive shaft, not removable sleeve-Removability not invention-(ii) That validity of '803 patent in Canada not attacked until 16 years after inception, and after expiry in United States, imposing heavy onus on defendant to prove invalidity-But onus shifting to patentee once attacking party showing some evidence of invalidity on balance of probabilities-Defendants not showing, even on balance of probabilities, '803 patent invalid-Presumption of validity prevailing-(iii) Burden of establishing infringement on balance of probabilities on plaintiffs-That defendants' agitator not removable not defence to allegation of infringement-Defendants' non-removable auger "minor variant"-Removability not materially affecting how invention working in large loads-Although element identified as "sleeve" in claims of '803 patent not present on defendants' agitator, upper auger of defendants' agitator falling within scope of '803 patent-But not determinative of infringement-That defendants' agitator having flex vanes on lower oscillating portion determinative of infringement-'803 patent mute on type of vanes to be used-Dual action agitator with flex vanes cannot be invention disclosed by '803 patent as at time of invention use of flex vanes not contemplated with dual action agitation-'803 patent only contemplating rigid vanes-Agitator with flex vanes, although not specifically excluded from '803 patent, not included in '803 patent-Not infringed by defendants' agitator-(2)(i) As language of '734 patent clear, unambiguous, easily understandable, no need to look further than claims of patent to aid in its construction-Patent for unidirectional upper auger and oscillating lower agitator equipped with flex vanes, powered by one-way clutch-Major differentiating characteristics of '734 patent requirements vanes on lower agitator be flexible, but need not be co-axially aligned to lower agitator, and drive continuously and/or intermittently rotating in one direction-(ii) Only novelty, inventiveness of '734 patent, and whether sufficient evidence of invalidity to defeat statutory presumption of validity at issue-Defendants not producing evidence tending to disprove on balance of probabilities novelty of addition of flex vanes to dual action environment-Presumption of novelty of '734 patent prevailing in absence of evidence to contrary-As to inventiveness, question whether, by putting together all elements of '734 patent, patentee producing inventive "combination", or mere aggregation of well-known elements-If former, next question whether addition of flex vanes obvious-Addition of upper auger or flex vanes creating new, common result-Elements combine for unitary result-Advance disclosed in '734 patent not mere aggregation of previously known parts-Defendants not disproving inventiveness-Use of flex vanes on dual action agitator not obvious-That took six months to develop inventive step of adding flex vanes to dual action agitator evidence of serious thought, research, experimentation-Improvement to patented invention patentable if has novelty, utility, invention-As '734 patent not merely aggregation of previously known parts, impossible to isolate flex vanes from rest of invention-Invention not merely substitution of flex for rigid vanes-No need to analyze whether substitution obvious-Contents of patent coming into public domain only after patent issued-Due to issuance dates of three patents, knowledge contained in '401, '903 patents in public domain for just over two years before '734 patent issued-This knowledge not in public domain at time of actual invention disclosed in '734 patent-General rule co-pending patents may not be cited as prior art against each other-Applications co-pending-'401, '803 patents not prior art even though cited as prior art in '734 patent, because co-pending at time of invention-Defendants not establishing any evidence tending to prove on balance of probabilities '401, '803 patents can be considered prior art to '734 patent-As '734 patent for entirely different invention than inventions disclosed in '401, '803 patents, no double-patenting-Defendants not showing on balance of probabilities invention disclosed in '734 patent lacking novelty or inventiveness in any way-No evidence tending to dissolve presumption of validity-'734 patent therefore valid-(iii) Defendants' agitator falling substantively within claims of '734 patent-Defendants guilty of infringement.