# Relationship history for MSHA mine 1516703

Current hierarchy: **Davis Edward W → Bremen Minerals Inc → Buttonsberry Mine**

- 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:** Bremen Minerals Inc → Buttonsberry Mine; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Davis Edward W → Buttonsberry Mine; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Davis Edward W → Bremen Minerals Inc; 1989-08-01 to current/open; source msha-controller-operator-history