# Relationship history for MSHA mine 0102524

Current hierarchy: **Parker Roy → Roy Parker & Sons Sand & Gravel → Parker No 2**

- 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:** Roy Parker & Sons Sand & Gravel → Parker No 2; 1983-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Parker Roy → Parker No 2; 1983-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Parker Roy → Roy Parker & Sons Sand & Gravel; 1983-02-01 to current/open; source msha-controller-operator-history