# Relationship history for MSHA mine 3301411

Current hierarchy: **Matthew J  Briggs → Briggs Sand and Gravel Inc → Briggs Sand and Gravel Inc**

- 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

- **operator_operates_mine:** Briggs Sand and Gravel Inc → Briggs Sand and Gravel Inc; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** James A  Briggs → Briggs Sand and Gravel Inc; 1950-01-01 to 2022-07-24; source msha-controller-operator-history
- **controller_controls_operator:** James A  Briggs → Briggs Sand and Gravel Inc; 1950-01-01 to 2022-07-24; source msha-controller-operator-history
- **controller_controls_mine:** Matthew J  Briggs → Briggs Sand and Gravel Inc; 2022-07-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matthew J  Briggs → Briggs Sand and Gravel Inc; 2022-07-25 to current/open; source msha-controller-operator-history