# Relationship history for MSHA mine 0505199

Current hierarchy: **Mike T  Anson → Anson Excavating & Pipe Inc. → 4A Rock Products- Nichols Pit**

- 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

- **controller_controls_mine:** Mike T  Anson → 4A Rock Products- Nichols Pit; 2013-06-26 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Anson Excavating & Pipe Inc. → 4A Rock Products- Nichols Pit; 2025-04-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mike T  Anson → Anson Excavating & Pipe Inc.; 2025-04-23 to current/open; source msha-controller-operator-history