The NFL confirmed that it has ended its helmet deal with Riddell, and the 2013-14 season will be the last season Riddell will be the official helmet of the league.
According to ESPN:
But during the past few years, as the league became increasingly focused on concussions, NFL officials were more concerned about the implication of selling exclusive branding rights to one helmet company over another. At an NFL-sponsored youth Play 60 event last year in New York City, the league had a variety of helmet manufacturers displaying their products to children and parents.
NFL players can wear any helmet they want as long as it complies with prescribed standards, but Riddell is the only company whose name can appear on the helmet’s nose bumper. For the roughly one-third of the league’s players who don’t use a Riddell helmet — and instead use its competitors, including Schutt, Xenith and Rawlings — the nose bumper plate remains blank.