# Relationship history for MSHA mine 1700619

Current hierarchy: **Lynn  Lakeman → Vaughn Thibodeau & Sons Inc → Ammo Park Quarry**

- 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:** Vaughn Thibodeau & Sons Inc → Ammo Park Quarry; 1993-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Vaughn  Thibodeau et al → Ammo Park Quarry; 1993-07-01 to 2007-12-10; source msha-controller-operator-history
- **controller_controls_operator:** Vaughn  Thibodeau et al → Vaughn Thibodeau & Sons Inc; 1993-07-01 to 2007-12-10; source msha-controller-operator-history
- **controller_controls_mine:** Lynn  Lakeman → Ammo Park Quarry; 2007-12-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lynn  Lakeman → Vaughn Thibodeau & Sons Inc; 2007-12-11 to current/open; source msha-controller-operator-history
