# Relationship history for MSHA mine 1500825

Current hierarchy: **Gibson Dan → Dan Gibson Coal Co → No 1 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:** V & W Coal Company → No 1 Mine; 1950-01-01 to 1973-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Frazier Glen & Dan Gibson → No 1 Mine; 1950-01-01 to 1973-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Frazier Glen & Dan Gibson → V & W Coal Company; 1950-01-01 to 1973-07-31; source msha-controller-operator-history
- **operator_operates_mine:** D M Coal Co → No 1 Mine; 1973-08-01 to 1973-11-25; source msha-controller-operator-history
- **controller_controls_mine:** Everidge Bobby Dale Hall Et Al → No 1 Mine; 1973-08-01 to 1973-11-25; source msha-controller-operator-history
- **controller_controls_operator:** Everidge Bobby Dale Hall Et Al → D M Coal Co; 1973-08-01 to 1973-11-25; source msha-controller-operator-history
- **operator_operates_mine:** Dan Gibson Coal Co → No 1 Mine; 1973-11-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gibson Dan → No 1 Mine; 1973-11-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gibson Dan → Dan Gibson Coal Co; 1973-11-26 to current/open; source msha-controller-operator-history