# Relationship history for MSHA mine 1510141

Current hierarchy: **Eagle Coal & Dock Company Inc → Somerset Coal Company → Somerset No 1**

- 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:** Keathley Joe R → Somerset No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Watson Shadrey → Somerset No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Watson & Cassady Coal Company → Somerset No 1; 1976-12-01 to 1981-02-19; source msha-controller-operator-history
- **controller_controls_operator:** Watson Shadrey → Watson & Cassady Coal Company; 1976-12-01 to 1981-02-19; source msha-controller-operator-history
- **operator_operates_mine:** Phyllis Coal Company Inc → Somerset No 1; 1981-02-20 to 1981-06-29; source msha-controller-operator-history
- **controller_controls_operator:** Keathley Joe R → Phyllis Coal Company Inc; 1981-02-20 to 1981-06-29; source msha-controller-operator-history
- **operator_operates_mine:** Somerset Coal Company → Somerset No 1; 1981-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Eagle Coal & Dock Company Inc → Somerset No 1; 1981-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eagle Coal & Dock Company Inc → Somerset Coal Company; 1981-06-30 to current/open; source msha-controller-operator-history