The competition has been organised by the Fédération Française de Rugby since 2000, when it replaced the B2 Group.
The championship is contested between 40 teams and named in honor of the famous former FC Lourdes and French International player, Jean Prat.
Preliminary phase A total of 10 teams compete on a double round-robin basis (18 games) in each of the 4 groups.
Through the 2019–20 season, two teams will continue to be promoted each season, but the second promotion place will go to a "wildcard" club selected by Ligue Nationale de Rugby, which operates the Top 14 and Pro D2.
The "wildcard" club must be located north of a line running roughly from La Rochelle to Lyon, and show itself to be capable of transitioning to fully professional rugby.