# Relationship history for MSHA mine 4104445

Current hierarchy: **Melvin J  Threadgill → M & T Natural Stone → M & T Natural Stone**

- 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:** C & M Materials → M & T Natural Stone; 2003-10-21 to 2004-04-11; source msha-controller-operator-history
- **controller_controls_mine:** John  Chamberlin  et al → M & T Natural Stone; 2003-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Chamberlin  et al → C & M Materials; 2003-10-21 to 2004-04-11; source msha-controller-operator-history
- **controller_controls_operator:** George  Marino  et al → C & M Materials; 2003-10-21 to 2004-04-11; source msha-controller-operator-history
- **operator_operates_mine:** M & T Natural Stone → M & T Natural Stone; 2004-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Melvin J  Threadgill → M & T Natural Stone; 2004-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Melvin J  Threadgill → M & T Natural Stone; 2004-04-12 to current/open; source msha-controller-operator-history