# Relationship history for MSHA mine 3603431

Current hierarchy: **Gary A  Mahan → Pen Roc Inc → Pen Roc Incorporated**

- 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:** Gold Bond Building Products → Pen Roc Incorporated; 1950-01-01 to 1989-12-06; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → Pen Roc Incorporated; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Gold Bond Building Products; 1950-01-01 to 1989-12-06; source msha-controller-operator-history
- **operator_operates_mine:** Pen Roc Inc → Pen Roc Incorporated; 1989-12-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gary A  Mahan  et al → Pen Roc Incorporated; 1989-12-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary A  Mahan  et al → Pen Roc Inc; 1989-12-07 to current/open; source msha-controller-operator-history