# Relationship history for MSHA mine 1508625

Current hierarchy: **Combs Robert & Asbel Adkins → C & A Coal Company → 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:** Omega Mining Company Inc → No 1 Mine; 1975-08-01 to 1977-08-18; source msha-controller-operator-history
- **controller_controls_mine:** Davidson Mart → No 1 Mine; 1975-08-01 to 1977-08-18; source msha-controller-operator-history
- **controller_controls_operator:** Davidson Mart → Omega Mining Company Inc; 1975-08-01 to 1977-08-18; source msha-controller-operator-history
- **operator_operates_mine:** Omega Mining Company Inc → No 1 Mine; 1977-08-19 to 1978-04-23; source msha-controller-operator-history
- **controller_controls_mine:** Lawson Arthur Et Al → No 1 Mine; 1977-08-19 to 1978-04-23; source msha-controller-operator-history
- **controller_controls_operator:** Lawson Arthur Et Al → Omega Mining Company Inc; 1977-08-19 to 1978-04-23; source msha-controller-operator-history
- **operator_operates_mine:** C & A Coal Company → No 1 Mine; 1978-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Combs Robert & Asbel Adkins → No 1 Mine; 1978-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Combs Robert & Asbel Adkins → C & A Coal Company; 1978-04-24 to current/open; source msha-controller-operator-history