# Relationship history for MSHA mine 3607421

Current hierarchy: **Coleman Joe & Thurman Jr → Coleman & Coleman Drilling Company → Silverbrook Stripping**

- 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

- **controller_controls_mine:** Coleman Joe & Thurman Jr → Silverbrook Stripping; 1975-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Coleman & Coleman Drilling Company → Silverbrook Stripping; 1983-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Coleman Joe & Thurman Jr → Coleman & Coleman Drilling Company; 1983-01-01 to current/open; source msha-controller-operator-history