Riordan v. The Queen, 2005 DTC 397, 2005 TCC 150 -- summary under Subsection 163(2)

The taxpayer was subject to the penalty for failure to report over $1 million of employee stock option benefits realized by him over a four-year period notwithstanding that no T4 slips were issued to him. He made no effort to inform himself of the tax treatment of the benefits, the omission of the benefits was not an error an average taxpayer would make, his lack of disclosure was not merely a failure to use reasonable care but reflected indifference as to whether the law was complied with, the amounts were in excess of his annual employment income, and the applicable standard of care was greater than that for a taxpayer of marginal intelligence.