The taxpayer claimed privilege in respect of communications between the appellant, two affiliates in Australia and Italy, their UK parent, and their respective legal counsel (totaling five firms).
D'Arcy J found that neither the taxpayer nor its affiliates had breached the confidentiality of advice from counsel (and thus waived privilege) when the companies' employees shared the advice with each other. Under the principle of common interest privilege, solicitor-client privilege was not waived given that the shared legal advice "was obtained by all the parties to facilitate the completion of the transactions and was for the benefit of all parties" (para. 66).
However, D'Arcy J found that the taxpayer had waived privilege in respect of emails of a Canadian tax lawyer, which were addressed primarily to an individual at its U.K. parent but also were sent to the Australian affiliate's external accountants ("PWC"). Although Susan Hosiery established that privilege was not lost with respect to communications received or given by counsel to accountants acting in that regard on behalf of the client, the taxpayer failed to establish "that PWC Australia's role, whatever it was, extended to any function which could be said to be integral to the solicitor-client relationship" (para. 77).