# Relationship history for MSHA mine 4601979

Current hierarchy: **Robinette Donna → Fossil Fuels Inc → Left Fork #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:** United Coal Company → Left Fork #1 Mine; 1950-01-01 to 1987-11-03; source msha-controller-operator-history
- **controller_controls_mine:** Garland Robert L → Left Fork #1 Mine; 1950-01-01 to 1987-11-03; source msha-controller-operator-history
- **controller_controls_operator:** Garland Robert L → United Coal Company; 1950-01-01 to 1987-11-03; source msha-controller-operator-history
- **controller_controls_mine:** Horn Steve → Left Fork #1 Mine; 1987-04-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Tug Huff Coal Corp → Left Fork #1 Mine; 1987-11-04 to 1989-01-19; source msha-controller-operator-history
- **controller_controls_operator:** Horn Steve → Tug Huff Coal Corp; 1987-11-04 to 1989-01-19; source msha-controller-operator-history
- **operator_operates_mine:** Fossil Fuels Inc → Left Fork #1 Mine; 1989-01-20 to 1989-10-19; source msha-controller-operator-history
- **controller_controls_mine:** Lyall Jerry Et Al → Left Fork #1 Mine; 1989-01-20 to 1989-10-19; source msha-controller-operator-history
- **controller_controls_operator:** Lyall Jerry Et Al → Fossil Fuels Inc; 1989-01-20 to 1989-10-19; source msha-controller-operator-history
- **operator_operates_mine:** Fossil Fuels Inc → Left Fork #1 Mine; 1989-10-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robinette Donna → Left Fork #1 Mine; 1989-10-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robinette Donna → Fossil Fuels Inc; 1989-10-20 to current/open; source msha-controller-operator-history