# Relationship history for MSHA mine 4402274

Current hierarchy: **Robert C  Gregory Sr. → Gregory Coal Corp → Mine #1**

- 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:** Smitty Baker Coal Company Inc → Mine #1; 1950-01-01 to 1972-02-29; source msha-controller-operator-history
- **controller_controls_mine:** Baker Ralph → Mine #1; 1950-01-01 to 1986-05-21; source msha-controller-operator-history
- **controller_controls_operator:** Baker Ralph → Smitty Baker Coal Company Inc; 1950-01-01 to 1972-02-29; source msha-controller-operator-history
- **operator_operates_mine:** P & P Coal Company Inc → Mine #1; 1972-03-01 to 1978-06-29; source msha-controller-operator-history
- **controller_controls_mine:** Poe Clyde & Charles James → Mine #1; 1972-03-01 to 1978-06-29; source msha-controller-operator-history
- **controller_controls_operator:** Poe Clyde & Charles James → P & P Coal Company Inc; 1972-03-01 to 1978-06-29; source msha-controller-operator-history
- **operator_operates_mine:** Gregory Coal Corp → Mine #1; 1978-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert C  Gregory Sr. → Mine #1; 1978-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert C  Gregory Sr. → Gregory Coal Corp; 1978-06-30 to current/open; source msha-controller-operator-history