# Relationship history for MSHA mine 3604675

Current hierarchy: **Heidelberg Materials AG → Hanson Aggregates BMC, Inc → Penn Valley 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:** Warner Company → Penn Valley Sand & Gravel; 1950-01-01 to 1990-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Warner Company → Penn Valley Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warner Company → Warner Company; 1950-01-01 to 1990-07-19; source msha-controller-operator-history
- **operator_operates_mine:** Warner Company → Penn Valley Sand & Gravel; 1990-07-20 to 2002-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Wmx Technologies Inc → Penn Valley Sand & Gravel; 1990-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wmx Technologies Inc → Warner Company; 1990-07-20 to 2002-02-28; source msha-controller-operator-history
- **controller_controls_mine:** USS Holdings Inc → Penn Valley Sand & Gravel; 1996-03-09 to 2003-07-18; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates BMC, Inc → Penn Valley Sand & Gravel; 2002-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** USS Holdings Inc → Hanson Aggregates BMC, Inc; 2002-03-01 to 2003-07-18; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Penn Valley Sand & Gravel; 2003-07-19 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates BMC, Inc; 2003-07-19 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Penn Valley Sand & Gravel; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates BMC, Inc; 2007-08-23 to current/open; source msha-controller-operator-history