# Relationship history for MSHA mine 0200731

Current hierarchy: **Hart Philip → Hart Enterprises → Hart Enterprises**

- 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:** Willcox Rock & Sand Inc → Hart Enterprises; 1950-01-01 to 1988-11-29; source msha-controller-operator-history
- **controller_controls_mine:** Keith  Gallagher → Hart Enterprises; 1950-01-01 to 2011-08-28; source msha-controller-operator-history
- **controller_controls_operator:** Keith  Gallagher → Willcox Rock & Sand Inc; 1950-01-01 to 1988-11-29; source msha-controller-operator-history
- **operator_operates_mine:** Hart Enterprises → Hart Enterprises; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hart Philip → Hart Enterprises; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hart Philip → Hart Enterprises; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shaye E  Klump et al → Hart Enterprises; 2011-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shaye E  Klump et al → Willcox Rock & Sand Inc; 2011-08-29 to 1988-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Kelly L  Owen et al → Willcox Rock & Sand Inc; 2011-08-29 to 1988-11-29; source msha-controller-operator-history