# Relationship history for MSHA mine 2601800

Current hierarchy: **Armstrong Edwin G → Edwin G Armstrong → Rainbow 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:** Edwin G Armstrong → Rainbow Mine; 1982-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Armstrong Edwin G → Rainbow Mine; 1982-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Armstrong Edwin G → Edwin G Armstrong; 1982-06-01 to current/open; source msha-controller-operator-history