This article might be a good starting place: http://www.bloomberg.com/features/2015-how-amex-lost-costco/ http://www.bloomberg.com/features/2015-how-amex-lost-c

This article might be a good starting place: http://www.bloomberg.com/features/2015-how-amex-lost-costco/ http://www.bloomberg.com/features/2015-how-amex-lost-costco/