401. A taxpayer not contemplated in section 400 may deduct, in computing the income of the taxpayer for a taxation year, an amount not exceeding the aggregate of(a) the amount by which the taxpayer’s cumulative Canadian exploration expense at the end of the year exceeds the amount designated by the taxpayer for the year for the purposes of the Income Tax Act (Revised Statutes of Canada, 1985, chapter 1, 5th Supplement) under subsection 14.1 of section 66 of the said Act, and
(b) the amount by which the aggregate determined under subparagraph i of paragraph a of section 418.31.1 in respect of the taxpayer for the year exceeds the amount that would be determined in respect of the taxpayer for the year under paragraph d of section 330 if the aggregate last referred to in the said paragraph d were not taken into account.