# Relationship history for MSHA mine 1512431

Current hierarchy: **MAPCO Inc → Pontiki Coal Corp → Pontiki No 3 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:** MAPCO Inc → Pontiki No 3 Mine; 1975-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Pontiki Coal Corp → Pontiki No 3 Mine; 1980-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MAPCO Inc → Pontiki Coal Corp; 1980-07-01 to current/open; source msha-controller-operator-history