# Relationship history for MSHA mine 1510285

Current hierarchy: **Nick A  Cooley → Bluebird Collieries Inc → No 1 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Nick A  Cooley et al → No 1 Tipple; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bluebird Collieries Inc → No 1 Tipple; 1977-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nick A  Cooley et al → Bluebird Collieries Inc; 1977-02-01 to current/open; source msha-controller-operator-history