# Relationship history for MSHA mine 1700746

Current hierarchy: **Patrick R  Cyr; Barbara J  Cyr → Sabattus Sand & Gravel → Sabattus  Sand & Gravel  Portable Unit 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Barbara J  Cyr et al → Sabattus  Sand & Gravel  Portable Unit 1; 1980-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sabattus Sand & Gravel → Sabattus  Sand & Gravel  Portable Unit 1; 2003-06-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Barbara J  Cyr et al → Sabattus Sand & Gravel; 2003-06-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick R  Cyr et al → Sabattus Sand & Gravel; 2003-06-02 to current/open; source msha-controller-operator-history