The 2012 Clydesdale Bank 40 tournament was the third season of the ECB 40 limited overs cricket competition for the English and Welsh first-class counties. In addition to the 18 counties, Scotland and the Netherlands took part, as well as the Unicorns, a team of players who did not have first-class contracts.
The competition consisted of three groups of seven teams, from which the top team from each group, plus the best second-placed team, progressed to the semi-finals. The groups were allocated randomly.
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