# Relationship history for MSHA mine 4603271

Current hierarchy: **Ashland Inc → Sharples Coal Corp → No 1 Central Shop**

- 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:** Zapata Coal Corp → No 1 Central Shop; 1950-01-01 to 1978-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Zapata Corp → No 1 Central Shop; 1950-01-01 to 1978-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Zapata Corp → Zapata Coal Corp; 1950-01-01 to 1978-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Dal-Tex Coal Corp → No 1 Central Shop; 1978-02-01 to 1986-08-24; source msha-controller-operator-history
- **controller_controls_mine:** United  Company → No 1 Central Shop; 1978-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Dal-Tex Coal Corp; 1978-02-01 to 1986-08-24; source msha-controller-operator-history
- **operator_operates_mine:** Sharples Coal Corp → No 1 Central Shop; 1986-08-25 to 1992-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Allen T  Workman Jr → No 1 Central Shop; 1986-08-25 to 1992-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Allen T  Workman Jr → Sharples Coal Corp; 1986-08-25 to 1992-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Sharples Coal Corp → No 1 Central Shop; 1992-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc et al → No 1 Central Shop; 1992-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc et al → Sharples Coal Corp; 1992-04-01 to current/open; source msha-controller-operator-history