# Relationship history for MSHA mine 1700704

Current hierarchy: **Bruce  Obert → Bruce R Obert & Sons LLC → B R Obert 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

- **operator_operates_mine:** Bruce R Obert & Sons → B R Obert Pit; 2001-06-01 to 2006-09-14; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Obert → B R Obert Pit; 2001-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Obert → Bruce R Obert & Sons; 2001-06-01 to 2006-09-14; source msha-controller-operator-history
- **operator_operates_mine:** Bruce R Obert & Sons LLC → B R Obert Pit; 2006-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Obert → B R Obert Pit; 2006-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Obert → Bruce R Obert & Sons LLC; 2006-09-15 to current/open; source msha-controller-operator-history