# Relationship history for MSHA mine 0502897

Current hierarchy: **Healey Buddy J → H & H Coal Enterprises → Healey 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

- **controller_controls_mine:** Horner William R → Healey Strip; 1975-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sunshine Coal Company → Healey Strip; 1976-05-01 to 1976-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Bingel J → Healey Strip; 1976-05-01 to 1976-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Bingel J → Sunshine Coal Company; 1976-05-01 to 1976-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Horner Coal Company → Healey Strip; 1977-01-01 to 1982-09-26; source msha-controller-operator-history
- **controller_controls_operator:** Horner William R → Horner Coal Company; 1977-01-01 to 1982-09-26; source msha-controller-operator-history
- **operator_operates_mine:** H & H Coal Enterprises → Healey Strip; 1982-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Healey Buddy J → Healey Strip; 1982-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Healey Buddy J → H & H Coal Enterprises; 1982-09-27 to current/open; source msha-controller-operator-history