https://en.wikipedia.org/wiki/Hilary_Page#Kiddicraft

Specifically:

> Ole Kirk Christiansen and his son Godtfred became aware of the Kiddicraft brick after examining a sample, and possibly drawings, given to them by the British supplier of the first injection moulding machine they had purchased. Realising their potential, Ole copied the Kiddicraft brick and in 1949 marketed his own version, The Automatic Binding Brick, that became the Lego brick in 1953.