The 2007 season heralded the end of the existing Concorde Agreement between the existing Formula One constructors and Bernie Ecclestone. In particular, Mercedes-Benz, BMW, and Honda (collectively the Grand Prix Manufacturers' Association) had a number of outstanding disagreements with the FIA and Ecclestone on financial and technical grounds. They had threatened to boycott Formula One from the 2008 season onwards and instead stage their own rival series, before signing a memorandum of understanding (MoU) at the 2006 Spanish Grand Prix.