# Relationship history for MSHA mine 1515764

Current hierarchy: **Mills Randy → T K G B Coal Company → Mine #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

- **operator_operates_mine:** T K G B Coal Company → Mine #1; 1986-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mills Randy Et Al → Mine #1; 1986-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mills Randy Et Al → T K G B Coal Company; 1986-10-01 to current/open; source msha-controller-operator-history