Iggillis Holdings Inc. v. Canada (March 6, 2018 – 2018 FCA 51, Webb (author), Boivin, Rennie JJ.A.).
Précis: This is an appeal from a decision of the Federal Court which held that advisory common interest privilege was not a valid constituent form of solicitor-client privilege and accordingly allowed CRA’s application for the production by Iggillis Holdings of a document known as the “Abacus Memo” which had been produced by a lawyer for a third party and shared with Iggillis during the course of a purchase and sale transaction. The Federal Court of Appeal reversed this decision holding that the Abacus Memo was protected from disclosure by solicitor-client privilege. Thus the appeal was allowed and CRA’s application for production of the Memo was dismissed. The appellants were awarded costs both in the Federal Court and the Federal Court of Appeal.
Decision: The Court of Appeal found that the laws of British Columbia and Alberta were the applicable laws for determining the status of the Abacus Memo:
 In this case, the only provinces that were identified as being potential provinces for the purposes of this definition of solicitor-client privilege were Alberta and British Columbia. Therefore, the question is whether a superior court in Alberta or British Columbia would find that the Abacus memo is protected from disclosure by solicitor-client privilege. The question is not whether the New York Court of Appeals or the court of any other state in the United States would find that the Abacus memo was protected from disclosure by solicitor-client privilege.
The Court concluded that advisory common interest privilege was recognized by courts in both British Columbia and Alberta:
 In Fraser Milner Casgrain LLP v. Minister of National Revenue, 2002 BCSC 1344, 2003 D.T.C. 5048 (Fraser Milner Casgrain LLP), the British Columbia Supreme Court held that the documents disclosed by Fraser Milner Casgrain to persons who were not their clients but who were interested in completing certain transactions with their clients retained their status as privileged. The Court referred to the cases that were relied upon by Fraser Milner Casgrain (the petitioners):
7 The petitioners maintain the privilege attached to the documentation was not waived when it was disclosed to Group B because the disclosure was made to facilitate the common interest the two groups of companies shared in having the transaction successfully completed. They rely on Archean Energy Ltd. v. Canada (MNR) (1997), 202 A.R. 198 (Alta. Q.B.), Anderson Exploration Ltd. v. Pan-Alberta Gas Ltd.,  10 W.W.R. 633 (Alta. Q.B.) and St. Joseph Corp. v. Canada (Public Works and Government Services),  F.C.J. No. 361 (T.D.).
8 In Archean Energy, legal opinions concerning the tax consequences of a number of share purchases were developed for one company which subsequently provided them to a second company, the purchaser in the transactions. The opinions were held, on application by the purchaser under the Income Tax Act, to be privileged because they had been provided to further the common interest of having the transaction concluded and not with the intent of waiving the privilege attached. In Anderson Exploration, two corporations exchanged confidential documents of a proprietary nature in negotiating a merger. A legal opinion obtained by one was also given to the other. Later, in unrelated litigation involving a subsidiary of one of the corporations, the plaintiff sought access to the documents arising from the merger negotiations. The court held that the disclosure of the documents to third parties did not waive the privilege that attached to all of the documentation because of the common interest associated with their disclosure. And in St. Joseph, legal opinions exchanged in the course of a commercial transaction were held to be privileged given that the parties had a joint interest in ensuring its completion.
 Two of the cases referred to above were from Alberta. Therefore, there is no distinction between the law of Alberta and British Columbia in relation to the issue of common interest privilege.
As a result the Court of Appeal concluded that the Federal Court had erred in relying upon American precedent in the face of established Canadian authority:
 Based on the decisions of the courts in Alberta and British Columbia, solicitor-client privilege is not waived when an opinion provided by a lawyer to one party is disclosed, on a confidential basis, to other parties with sufficient common interest in the same transactions. This principle applies whether the opinion is first disclosed to the client of the particular lawyer and then to the other parties or simultaneously to the client and the other parties. In each case, the solicitor-client privilege that applies to the communication by the lawyer to his or her client of a legal opinion is not waived when that opinion is disclosed, on a confidential basis, to other parties with sufficient common interest in the same transactions.
 As noted above, when dealing with complex statutes such as the Income Tax Act, sharing of opinions may well lead to efficiencies in completing the transactions and the clients may well be better served as the application of the Income Tax Act will be of interest to all of the parties to the series of transactions. In my view, in the circumstances of this case, Abacus and Gillis had sufficient common interest in the transactions to warrant a finding that, in Alberta or British Columbia, the Abacus memo is protected from disclosure by solicitor-client privilege.
Thus the appeal was allowed and CRA’s application for production of the Memo was dismissed. The appellants were awarded costs both in the Federal Court and the Federal Court of Appeal.