David Allen Tanner is Director at WHITE MOUNTAINS INSURANCE GROUP LTD (WTM). They have made 2 open-market trades across 2 companies since 2018, most recently 2026-08-31.
CIK 0001318960
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
2 open-market purchases totalling $1.1M since 2018, never a sale. Too few scored purchases to measure a record yet.
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.