# Relationship history for MSHA mine 0600755

Current hierarchy: **Robert  Sachs → Cherry Hill Construction Company Inc → Metso HP200(SC21)S/N-76995**

- 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:** Robert  Sachs → Metso HP200(SC21)S/N-76995; 2001-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cherry Hill Construction Company Inc → Metso HP200(SC21)S/N-76995; 2009-01-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert  Sachs → Cherry Hill Construction Company Inc; 2009-01-06 to current/open; source msha-controller-operator-history