# Relationship history for MSHA mine 4405374

Current hierarchy: **Bolling Darrell J → Custom Coal Company → Mine No 1 Strip**

- 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:** Custom Coal Company → Mine No 1 Strip; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bolling Darrell J Et Al → Mine No 1 Strip; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bolling Darrell J Et Al → Custom Coal Company; 1980-02-01 to current/open; source msha-controller-operator-history