# Relationship history for MSHA mine 2500943

Current hierarchy: **Henthorn Robert E → Henthorn Sand & Gravel → Henthorn Sand & Gravel**

- 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

- **operator_operates_mine:** Dutcher Sand & Gravel → Henthorn Sand & Gravel; 1979-01-01 to 1988-07-13; source msha-controller-operator-history
- **controller_controls_mine:** Dutcher Jesse Martin & Jesse Marvin → Henthorn Sand & Gravel; 1979-01-01 to 1988-07-13; source msha-controller-operator-history
- **controller_controls_operator:** Dutcher Jesse Martin & Jesse Marvin → Dutcher Sand & Gravel; 1979-01-01 to 1988-07-13; source msha-controller-operator-history
- **operator_operates_mine:** Henthorn Sand & Gravel → Henthorn Sand & Gravel; 1988-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Henthorn Robert E → Henthorn Sand & Gravel; 1988-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Henthorn Robert E → Henthorn Sand & Gravel; 1988-07-14 to current/open; source msha-controller-operator-history