# Relationship history for MSHA mine 2900182

Current hierarchy: **Meek Loyd → Western Gypsum Company → Rosario Gypsum 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Western Mining Company → Rosario Gypsum Mine; 1950-01-01 to 1984-02-27; source msha-controller-operator-history
- **controller_controls_mine:** Griffin H → Rosario Gypsum Mine; 1950-01-01 to 1984-02-27; source msha-controller-operator-history
- **controller_controls_operator:** Griffin H → Western Mining Company; 1950-01-01 to 1984-02-27; source msha-controller-operator-history
- **operator_operates_mine:** Hutchens Mining → Rosario Gypsum Mine; 1984-02-28 to 1987-09-07; source msha-controller-operator-history
- **controller_controls_mine:** Hutchens Merle → Rosario Gypsum Mine; 1984-02-28 to 1987-09-07; source msha-controller-operator-history
- **controller_controls_operator:** Hutchens Merle → Hutchens Mining; 1984-02-28 to 1987-09-07; source msha-controller-operator-history
- **operator_operates_mine:** Western Gypsum Company → Rosario Gypsum Mine; 1987-09-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Meek Loyd → Rosario Gypsum Mine; 1987-09-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Meek Loyd → Western Gypsum Company; 1987-09-08 to current/open; source msha-controller-operator-history