# Relationship history for MSHA mine 0203092

Current hierarchy: **Shirley J  Hammond → Hammond Wholesale Flagstone Inc → Switch Back**

- 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

- **controller_controls_mine:** Horner James E → Switch Back; 1997-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shirley J  Hammond → Switch Back; 1999-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Horner Stone Inc → Switch Back; 2005-07-01 to 2007-10-24; source msha-controller-operator-history
- **controller_controls_operator:** Horner James E → Horner Stone Inc; 2005-07-01 to 2007-10-24; source msha-controller-operator-history
- **operator_operates_mine:** Hammond Wholesale Flagstone Inc → Switch Back; 2007-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shirley J  Hammond → Hammond Wholesale Flagstone Inc; 2007-10-25 to current/open; source msha-controller-operator-history