# Relationship history for MSHA mine 3604937

Current hierarchy: **Joy Edwin & Evan Williams → J & W Coal Company → J And W Strip**

- 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:** J & W Coal Company → J And W Strip; 1974-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joy Edwin & Evan Williams → J And W Strip; 1974-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joy Edwin & Evan Williams → J & W Coal Company; 1974-01-08 to current/open; source msha-controller-operator-history