Reliance Electric Industrial Co. v. Northern Telecom Ltd.
A-534-89
Mahoney J.A.
21/10/92
4 pp.
Appeal from Trial Division decision ((1989), 28 C.P.R. (3d) 397) declaring claims 1, 2, 7 and 8 of Canadian Patent No. 1,029,084 invalid as claim 1 found to be vague and lacking in specificity -- Invention in issue Line protector for communication circuit to prevent damage of overvoltage -- Conditional findings by Trial Judge as to obviousness and infringement so unclear as to require matter be referred back to Trial Judge for resumption of trial if finding of invalidity erroneous -- Principal attack on judgment: interchangeability advantage of invention, not invention-Absence of reference to advantage in claim 1 no basis for declaring claim invalid for vagueness -- Other ground of vagueness should be revisited by Trial Judge upon proper analysis -- Appeal allowed.