# Relationship history for MSHA mine 3304591

Current hierarchy: **W Thomas  Mackall → Sterling Mining Corporation → Shean Hill Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** W Thomas  Mackall et al → Shean Hill Mine; 1991-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sterling Mining Corporation → Shean Hill Mine; 2007-07-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** W Thomas  Mackall et al → Sterling Mining Corporation; 2007-07-27 to current/open; source msha-controller-operator-history