In a welcome decision for Canadian acquirors and targets, the Tax Court of Canada recognized, in Rio Tinto Alcan Inc. v The Queen, that certain oversight expenses—including certain investment banking and other professional advisory fees—should be deductible in the context of M&A transactions. This is particularly so where such services are provided to enable the board of directors of the acquiror or target to determine whether to proceed with the transaction. The Court also established a principled basis for the deductibility of transaction expenses in a far broader set of circumstances than those previously accepted by the Canada Revenue Agency (the CRA), in particular, in situations in which a board is discharging its oversight function prior to a decision to implement a particular transaction(s). The decision is under appeal; if affirmed, it will represent a significant expansion of the deductibility of transaction fees. The onus will remain on the taxpayer to prove the expenses are deductible based on the new criteria; engagement letters for advisors and their invoices, clearly demarcating oversight activities in respect of proposed transaction(s) from the implementation phases, should be prepared accordingly. C. Kennedy and A. Nijhawan, "Rio Tinto Alcan v. The Queen: Welcome Expansion of the Canadian Tax Deductibility of M&A Transaction Expenses" Vol 36 No. 2 (February 2017) ABA Tax Times (American Bar Association, 2017).