# Relationship history for MSHA mine 2102403

Current hierarchy: **Wagner Clifford & Dennis → Clifford & Dennis Wagner Construction → Wagner Sand And 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Bowman Construction Company Inc → Wagner Sand And Gravel; 1950-01-01 to 1978-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Darwin  Johnson  et al → Wagner Sand And Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Darwin  Johnson  et al → Bowman Construction Company Inc; 1950-01-01 to 1978-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Wagner Clifford & Dennis → Wagner Sand And Gravel; 1978-03-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Clifford & Dennis Wagner Construction → Wagner Sand And Gravel; 1978-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wagner Clifford & Dennis → Clifford & Dennis Wagner Construction; 1978-08-05 to current/open; source msha-controller-operator-history