Pattern races

Group races, also known as Pattern races, or Graded races in some jurisdictions, are the highest level of races in Thoroughbred horse racing. They include most of the world's iconic races, such as, in Europe, the Epsom Derby, Irish Derby and Prix de l'Arc de Triomphe, in Australia, the Melbourne Cup and in the United States, the Kentucky Derby and Breeders' Cup races. Victory in these races marks a horse as being particularly talented, if not exceptional, and they are extremely important in determining stud values. They are also sometimes referred to as Black type races, since any horse that has won one of these races is printed in bold type in sales catalogues.

In Australia, the Australian Pattern Committee recommends to the Australian Racing Board (ARB) which races shall be designated as Group races. The list of races approved by the ARB are accepted by the International Cataloguing Standards Committee (ICSC) for publication by The Jockey Club (US) in The Blue Book, thus providing international recognition for Australia's best races.

There are four grades of Group races in Australia:

Australia has a total of approximately 540 to 550 Group races from a season total of almost 21,000 races. These races were collectively known as Principal Races until about 1979. For a list of Group races see List of Australian Group races.

In Europe the designation of flat races is agreed by the European Pattern Committee. The Committee grade races into one of three levels, dependent on the average official ratings achieved by the first four finishers in a race over a three-year period. The breakdown is as follows:

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