# Relationship history for MSHA mine 4103903

Current hierarchy: **Heidelberg Materials AG → Campbell Concrete & Materials LLC → Sand Supply #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Heidelberg Materials AG → Sand Supply #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lehigh Portland Cement Company → Sand Supply #1; 1996-06-01 to 1998-04-03; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Lehigh Portland Cement Company; 1996-06-01 to 1998-04-03; source msha-controller-operator-history
- **controller_controls_mine:** Constar Inc  et al → Sand Supply #1; 1997-03-17 to 2012-01-09; source msha-controller-operator-history
- **operator_operates_mine:** Campbell Concrete & Materials LLC → Sand Supply #1; 1998-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Constar Inc  et al → Campbell Concrete & Materials LLC; 1998-04-04 to 2012-01-09; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Sand Supply #1; 2012-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Campbell Concrete & Materials LLC; 2012-01-10 to current/open; source msha-controller-operator-history