# Relationship history for MSHA mine 0502674

Current hierarchy: **Energy Fuels Coal Resources Ltd → Kerr Coal Corp → Marr Strip**

- 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:** T M C → Marr Strip; 1975-01-01 to 1977-10-07; source msha-controller-operator-history
- **controller_controls_mine:** Avery Irving F → Marr Strip; 1975-01-01 to 1977-10-07; source msha-controller-operator-history
- **controller_controls_operator:** Avery Irving F → T M C; 1975-01-01 to 1977-10-07; source msha-controller-operator-history
- **operator_operates_mine:** Kerr Coal Corp → Marr Strip; 1977-10-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Coal Resources Ltd → Marr Strip; 1977-10-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Energy Fuels Coal Resources Ltd → Kerr Coal Corp; 1977-10-08 to current/open; source msha-controller-operator-history