# Relationship history for MSHA mine 3604142

Current hierarchy: **Barr Chester & James R Doyle → B & D Coal Company → B & D Coal Company**

- 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

- **operator_operates_mine:** B & D Coal Company → B & D Coal Company; 1950-01-01 to 1980-10-13; source msha-controller-operator-history
- **controller_controls_mine:** Barr Chester & James R Doyle → B & D Coal Company; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Barr Chester & James R Doyle → B & D Coal Company; 1950-01-01 to 1980-10-13; source msha-controller-operator-history
- **operator_operates_mine:** B & D Coal Company → B & D Coal Company; 1980-10-14 to 1980-12-10; source msha-controller-operator-history
- **controller_controls_mine:** AOI Coal Company → B & D Coal Company; 1980-10-14 to 1980-12-10; source msha-controller-operator-history
- **controller_controls_operator:** AOI Coal Company → B & D Coal Company; 1980-10-14 to 1980-12-10; source msha-controller-operator-history
- **operator_operates_mine:** B & D Coal Company → B & D Coal Company; 1980-12-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Barr Chester & James R Doyle → B & D Coal Company; 1980-12-11 to current/open; source msha-controller-operator-history