Companies do IPO (Initial Public Offering) mainly to increase capitalization. The need to increase capital often comes in the face of reorganization or restructuring.
Reorganization is tantamount to lean and process improvement. Since Visa is going in that direction, perhaps there’s room for them to go Six Sigma later, that is if they haven’t done it yet.
Read about Visa going public on Global Business Watch.
Six Sigma : Your Resource for Strategic Management. Meikah Delid. Eversun Software 2006.