# Relationship history for MSHA mine 1511309

Current hierarchy: **Richard L  Cooper → T & K Mining Company Inc → Northern 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:** T & K Mining Company Inc → Northern Tipple; 1978-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard L  Cooper → Northern Tipple; 1978-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard L  Cooper → T & K Mining Company Inc; 1978-04-01 to current/open; source msha-controller-operator-history