At the risk of oversimplification: Concorde was built by Aérospatiale and BAC. Aérospatiale was one of several companies in the original Airbus consortium that merged to form EADS, which now owns the Airbus brand and manufactures aircraft under that brand. I think.
IIRC Airbus held the type cert and provided manufacturer support. My understanding is that it was partly (if not mainly) due to Airbus's unwillingness to continue to provide such support (a commercial decision) which forced the type's retirement.