The Committee of Management determines which players may enter the four invitational events.

It was a strictly invitational event where each player had to pay a fee of $25,000 to enter.

League members can earn points at local, state, and nationwide open invitational events.

Friday night is unique in that there are special invitational events when a particularly strong field of runners has been assembled.

The five invitational events and the number of pairs are:

The following table outlines the results for ranking and the invitational events.

All occurred in major European invitational events, most of which are defunct.

An annual invitational event is organized after an open call for entries.

A total of 1,500 athletes from 60 countries will compete in the 15-day invitational event.

The first time it was run as an invitational event was in 1968.