# Relationship history for MSHA mine 3609866

Current hierarchy: **John E  Spickerman → John E. Spickerman → Coldwell Quarry**

- 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:** John E. Spickerman → Coldwell Quarry; 2010-07-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John E  Spickerman → Coldwell Quarry; 2010-07-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John E  Spickerman → John E. Spickerman; 2010-07-27 to current/open; source msha-controller-operator-history