Rooke v. Canada (Attorney General), 2002 DTC 6442, 2002 FCA 393 (FCA) -- summary under Subsection 122.3(1)

A taxpayer spent approximately one-half of his time outside Canada, and his employment income was almost entirely attributable to engineering work done outside Canada. Sharlow J.A. rejected the interpretation advanced by the Crown that s. 122.3 required "employment outside Canada" as a condition that must be met throughout the qualifying period. Instead the provision only required that substantially all his duties of employment be performed outside Canada.