# Relationship history for MSHA mine 1510821

Current hierarchy: **Warren W E & Jonah → W E & Jonah Warren Coal Company Inc → Surface Mine No 4**

- 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:** Warren W E & Jonah → Surface Mine No 4; 1976-08-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** W E & Jonah Warren Coal Company Inc → Surface Mine No 4; 1977-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warren W E & Jonah → W E & Jonah Warren Coal Company Inc; 1977-10-01 to current/open; source msha-controller-operator-history