a play-off structure since the 2009–10 season to determine the champions, similar to that used in the English Premiership. For the first two seasons there were two groups and a knockout to determine a winner. Starting from the 2003–04 season until the 2008–09 season, the champions were determined from league performance, with all the teams in one league. From the 2017–18 season, the regular season employed a conference structure rather than a single round robin league, with 'derby games' between teams from the same nation being protected, and an expanded playoff structure. This allowed the competition to control the calendar, and control the number of games per team. League points are awarded using the bonus points system. Until and including the 2008–09 season, the champions were decided solely on the basis of who finished top of the league table, but since the 2009–10 season, the league champion has been decided by a play-off series, in line with other rugby club competitions such as Super Rugby, Top 14, and the English Premiership: at the conclusion of the regular season, the top four placed teams enter the semi-final stage, with the winner of the first vs fourth and second vs third play-offs entering the final (known as the "grand final" in 2010 and 2011). Two Italian teams – the former National Championship of Excellence team Benetton Treviso, and a new team, Aironi – joined the league starting with the 2010–11 season. Aironi was replaced by Zebre from the 2012–13 season. Through the 2012–13 season, the Welsh, Irish, Scottish and Italian rugby unions used the league as the sole determinant for Heineken Cup qualification, and from 2013–14 they use it as the sole means of qualification for the successor to the Heineken Cup, the European Rugby Champions Cup. Corporate organisation The legal name of the body running the competition is PRO Rugby Championship DAC, a private company limited by shares based in Ireland. The organisation is responsible for running and operating the URC and is currently owned equally by the Irish Rugby Football Union (IRFU), the Scottish Rugby Union (SRU) and the Welsh Rugby Union (WRU). The Italian Rugby Federation (FIR) may become a shareholder subject to it meeting certain conditions. The board of Celtic Rugby DAC is made up of representatives from the IRFU, SRU, WRU, ProRugby Wales, the FIR and the South African Rugby Union. The chief executive is Martin Anayi.