Mattabi Mines Ltd. v. Min. of Rev., [1982] CTC 382 (SCO), rev'd [1984] CTC 566 (Ont CA), which was, aff'd by [1988] 2 CTC 294, [1988] 2 S.C.R. 175 -- summary under Subsection 21(2)

The taxpayer overlooked making an election in "prescribed form" under a comparable provision of the Corporations Tax Act (Ontario), and the Minister accepted the taxpayer's tax returns as if the interest expenditures had been properly capitalized pursuant to a formal election. It was stated (at p.393), that the Minister was entitled to waive the statutory requirement for the making of an election, and that the taxpayer accordingly was later precluded from arguing that it was entitled to deduct the capitalized interest as an expense. [C.R.: 85(1)]