What is the equal authenticity rule on collective agreements between English and French?

35. According to the equal authenticity rule, both the English and French versions of a collective agreement are equally valid statement of the parties’ intentions. The shared meaning rule, for its part, provides that both versions being the expression of the same intention, arbitrators should, as far as possible, attempt to ascertain that intention through a determination of the shared or common meaning of the two versions. In applying those rules, it doesn’t matter whether one version is a translation of the other. The fact that a collective agreement might have been negotiated in English or in French or might have been drafted first in one language and then merely translated to the other language makes no difference. (See, Doré v. Verdun (City), 1997 CanLII 315 (SCC), [1997] 2 SCR 862.)