# Relationship history for MSHA mine 1509969

Current hierarchy: **Fred J  Cassetty → Alley-Cassetty Coal Company Inc → Parkway Tipple**

- 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:** Parkway Coal Company → Parkway Tipple; 1976-07-16 to 1985-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Anne  Hoke et al → Parkway Tipple; 1976-07-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anne  Hoke et al → Parkway Coal Company; 1976-07-16 to 1985-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Hoke et al → Parkway Coal Company; 1976-07-16 to 1985-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Alley-Cassetty Coal Company Inc → Parkway Tipple; 1986-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fred J  Cassetty → Parkway Tipple; 1986-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred J  Cassetty → Alley-Cassetty Coal Company Inc; 1986-01-01 to current/open; source msha-controller-operator-history