Kirkbi held patents for LEGO construction sets.
When the patents expired in Canada, Ritvik began manufacturing and selling interchangeable bricks.
Kirkbi claimed an unregistered trade-mark in the 'LEGO indicia' (the pattern of raised studs) and sued for passing off under s. 7(b) of the Trade-marks Act.
Ritvik challenged the constitutionality of s. 7(b).
The Supreme Court of Canada held that s. 7(b) is intra vires Parliament as a valid exercise of the general trade and commerce power.
However, Kirkbi's passing-off claim was dismissed because the doctrine of functionality bars purely functional designs from being the basis of a trade-mark, whether registered or unregistered.