What is a national hunt pattern race?

A steeple chase, hurdle race or National Hunt Flat Race is a Pattern Race if, in any particular year

5.1.1 it appears in the list of pattern races in the steeple chase and hurdle race section of the

Programme Book published by the Authority, or

5.1.2 in the case of a race run in Ireland, it appears as a pattern race in the Irish Racing Calendar.

Such pattern races are divided into Grades 1, 2 and 3