The current institutional shareholding score of White Mountains Insurance Group Ltd is 10.00, ranking 1 out of 117 in the Insurance industry. The latest institutional shareholding proportion is 95.65%, representing a quarter-over-quarter decrease of 7.61%. The largest institutional shareholder is ETHSX, holding a total of 55.11K shares, representing 2.16% of shares outstanding, with 1557.71% increase in holdings.