The current institutional shareholding score of American Express Co is 5.00, ranking 164 out of 397 in the Banking Services industry. The latest institutional shareholding proportion is 66.00%, representing a quarter-over-quarter decrease of 1.17%. The largest institutional shareholder is Warren Buffett, holding a total of 146.25M shares, representing 22.23% of shares outstanding, with 0.05% increase in holdings.