# Relationship history for MSHA mine 0100330

Current hierarchy: **Drummond Company Inc → Mulga Coal Company → Mulga 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

- **operator_operates_mine:** Mulga Coal Company → Mulga Mine; 1950-01-01 to 1982-12-16; source msha-controller-operator-history
- **controller_controls_mine:** Mead Corp → Mulga Mine; 1950-01-01 to 1982-12-16; source msha-controller-operator-history
- **controller_controls_operator:** Mead Corp → Mulga Coal Company; 1950-01-01 to 1982-12-16; source msha-controller-operator-history
- **operator_operates_mine:** Mulga Coal Company → Mulga Mine; 1982-12-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Drummond Company Inc → Mulga Mine; 1982-12-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Drummond Company Inc → Mulga Coal Company; 1982-12-17 to current/open; source msha-controller-operator-history