# Relationship history for MSHA mine 1502520

Current hierarchy: **Reed Rabon → Apache Mining Company → No 1 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:** U A C Industries → No 1 Mine; 1950-01-01 to 1972-01-08; source msha-controller-operator-history
- **controller_controls_mine:** Browning Grey → No 1 Mine; 1950-01-01 to 1972-01-08; source msha-controller-operator-history
- **controller_controls_operator:** Browning Grey → U A C Industries; 1950-01-01 to 1972-01-08; source msha-controller-operator-history
- **operator_operates_mine:** Point Mining Company → No 1 Mine; 1972-01-09 to 1973-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Potter Hobert E → No 1 Mine; 1972-01-09 to 1973-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Potter Hobert E → Point Mining Company; 1972-01-09 to 1973-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Apache Mining Company → No 1 Mine; 1973-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Reed Rabon → No 1 Mine; 1973-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Reed Rabon → Apache Mining Company; 1973-06-01 to current/open; source msha-controller-operator-history