# Relationship history for MSHA mine 1502855

Current hierarchy: **Stumbo German → B D S Coal Company Inc → Robin No 2 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

- **controller_controls_mine:** Jones Edgar Et Al → Robin No 2 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Vicki Coal Company → Robin No 2 Mine; 1950-01-01 to 1973-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Vicki Coal Company → Robin No 2 Mine; 1950-01-01 to 1973-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Vicki Coal Company → Vicki Coal Company; 1950-01-01 to 1973-05-31; source msha-controller-operator-history
- **operator_operates_mine:** J R M Coal Company Inc → Robin No 2 Mine; 1973-06-01 to 1980-07-23; source msha-controller-operator-history
- **controller_controls_operator:** Jones Edgar Et Al → J R M Coal Company Inc; 1973-06-01 to 1980-07-23; source msha-controller-operator-history
- **operator_operates_mine:** B D S Coal Company Inc → Robin No 2 Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stumbo German → Robin No 2 Mine; 1980-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stumbo German → B D S Coal Company Inc; 1980-07-24 to current/open; source msha-controller-operator-history