# Relationship history for MSHA mine 1508608

Current hierarchy: **Smith Clifford → C M & S Coal Company Inc → No 1 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:** S & P Coal Company → No 1 Strip; 1975-05-01 to 1981-08-05; source msha-controller-operator-history
- **controller_controls_mine:** Parsley Conrad--Charles Snyder & Clayton Williams → No 1 Strip; 1975-05-01 to 1981-08-05; source msha-controller-operator-history
- **controller_controls_operator:** Parsley Conrad--Charles Snyder & Clayton Williams → S & P Coal Company; 1975-05-01 to 1981-08-05; source msha-controller-operator-history
- **operator_operates_mine:** C M & S Coal Company Inc → No 1 Strip; 1981-08-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smith Clifford → No 1 Strip; 1981-08-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smith Clifford → C M & S Coal Company Inc; 1981-08-06 to current/open; source msha-controller-operator-history