Sorry, it's in the rule book...
1/ TRAVEL MUST INCLUDE A MINIMUM OF THREE CONTINENTS INCLUDING THE CONTINENT OF
ORIGIN.
ITINERARIES WHICH INCLUDE EUROPE AND THE SW PACIFIC MUST BE A MINIMUM OF FOUR
CONTINENTS.
TRAVEL BETWEEN AUSTRALIA AND EUROPE ON A SINGLE FLIGHT NUMBER IS CONSIDERED
TRAVELING SW - PACIFIC ASIA-EUROPE THROUGH THREE CONTINENTS.