# Relationship history for MSHA mine 3303874

Current hierarchy: **Osborn Robert & Tom Meeks → Black Run Gravel Company → Black Run Gravel #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:** Black Run Gravel Company → Black Run Gravel #1; 1981-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Osborn Robert & Tom Meeks → Black Run Gravel #1; 1981-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Osborn Robert & Tom Meeks → Black Run Gravel Company; 1981-10-01 to current/open; source msha-controller-operator-history