# Relationship history for MSHA mine 1519570

Current hierarchy: **Amy C  Hamilton → T&T Energy LLC → Bedrock**

- 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:** Amy C  Hamilton → Bedrock; 2008-08-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** T&T Energy LLC → Bedrock; 2011-03-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Amy C  Hamilton → T&T Energy LLC; 2011-03-24 to current/open; source msha-controller-operator-history