# Relationship history for MSHA mine 3401450

Current hierarchy: **Bankoff J → Bankoff Oil → Bankoff 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Bankoff Oil → Bankoff Mine; 1984-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bankoff J Et Al → Bankoff Mine; 1984-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bankoff J Et Al → Bankoff Oil; 1984-04-01 to current/open; source msha-controller-operator-history