# Relationship history for MSHA mine 4607028

Current hierarchy: **Robertson Jack → Paybra Mining Company Inc → No 1 Surface 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:** Rogers Olin D → No 1 Surface Mine; 1985-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robertson Jack → No 1 Surface Mine; 1985-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Twin Action Mining Company Inc → No 1 Surface Mine; 1985-10-01 to 1986-06-16; source msha-controller-operator-history
- **controller_controls_operator:** Rogers Olin D → Twin Action Mining Company Inc; 1985-10-01 to 1986-06-16; source msha-controller-operator-history
- **operator_operates_mine:** Paybra Mining Company Inc → No 1 Surface Mine; 1986-06-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robertson Jack → Paybra Mining Company Inc; 1986-06-17 to current/open; source msha-controller-operator-history