# Relationship history for MSHA mine 1517150

Current hierarchy: **Pittston Company → Holston Mining Inc → Pinson Ridge No 1**

- 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

- **controller_controls_mine:** Pittston Company → Pinson Ridge No 1; 1990-07-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Holston Mining Inc → Pinson Ridge No 1; 1991-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pittston Company → Holston Mining Inc; 1991-10-01 to current/open; source msha-controller-operator-history