# Relationship history for MSHA mine 0600669

Current hierarchy: **Richard  Geer; Thomas  Geer → Geer Construction Company Inc → Geer 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:** Geer Construction Company Inc → Geer Sand & Gravel; 1998-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** H David  Geer → Geer Sand & Gravel; 1998-12-01 to 2017-06-19; source msha-controller-operator-history
- **controller_controls_operator:** H David  Geer → Geer Construction Company Inc; 1998-12-01 to 2017-06-19; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Geer et al → Geer Sand & Gravel; 2017-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Geer et al → Geer Construction Company Inc; 2017-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas  Geer et al → Geer Construction Company Inc; 2017-06-20 to current/open; source msha-controller-operator-history