The Pro12 (known as the RaboDirect Pro12 for sponsorship reasons, formerly known as the Celtic League and the Magners League) is an annual rugby union competition involving 12 professional sides from Ireland, Italy, Scotland and Wales. The league is one of the three major professional leagues in Europe, along with the English Premiership and the French Top 14, that competed in the Heineken Cup through the 2013–14 season and will be involved in that competition's successor, the European Rugby Champions Cup, from 2014–15.