# Relationship history for MSHA mine 0300860

Current hierarchy: **Ben M Hogan Company Inc → St Francis Material Company → Bay Road Materials Pit & Plant**

- 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:** Warren Brothers Company Inc → Bay Road Materials Pit & Plant; 1950-01-01 to 1979-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc → Bay Road Materials Pit & Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Warren Brothers Company Inc; 1950-01-01 to 1979-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Ben M Hogan Company Inc → Bay Road Materials Pit & Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** St Francis Material Company → Bay Road Materials Pit & Plant; 1979-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ben M Hogan Company Inc → St Francis Material Company; 1979-03-01 to current/open; source msha-controller-operator-history