# Relationship history for MSHA mine 3601984

Current hierarchy: **Bixler William A & Ronnie → S & T Coal Company → Bixler 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** S & T Coal Company → Bixler Mine; 1950-01-01 to 1974-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Poletti Peter J & Larry M Et Al → Bixler Mine; 1950-01-01 to 1974-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Poletti Peter J & Larry M Et Al → S & T Coal Company; 1950-01-01 to 1974-08-31; source msha-controller-operator-history
- **operator_operates_mine:** S & T Coal Company → Bixler Mine; 1974-09-01 to 1977-03-21; source msha-controller-operator-history
- **controller_controls_mine:** Zerbe Dean R-Alvin V Bixler Et Al → Bixler Mine; 1974-09-01 to 1977-03-21; source msha-controller-operator-history
- **controller_controls_operator:** Zerbe Dean R-Alvin V Bixler Et Al → S & T Coal Company; 1974-09-01 to 1977-03-21; source msha-controller-operator-history
- **operator_operates_mine:** S & T Coal Company → Bixler Mine; 1977-03-22 to 1981-03-09; source msha-controller-operator-history
- **controller_controls_mine:** Bixler Alvin → Bixler Mine; 1977-03-22 to 1981-03-09; source msha-controller-operator-history
- **controller_controls_operator:** Bixler Alvin → S & T Coal Company; 1977-03-22 to 1981-03-09; source msha-controller-operator-history
- **operator_operates_mine:** S & T Coal Company → Bixler Mine; 1981-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bixler William A & Ronnie → Bixler Mine; 1981-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bixler William A & Ronnie → S & T Coal Company; 1981-03-10 to current/open; source msha-controller-operator-history