# Relationship history for MSHA mine 4406507

Current hierarchy: **Roy D  Simmons Jr → Rockbridge Stone Products, Inc. → Rockbridge Stone #2**

- 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:** Hupman Brothers Excavating Company → Rockbridge Stone #2; 1989-01-01 to 1999-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Charles B  Hupman → Rockbridge Stone #2; 1989-01-01 to 1999-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Charles B  Hupman → Hupman Brothers Excavating Company; 1989-01-01 to 1999-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Roy D  Simmons Jr → Rockbridge Stone #2; 1993-01-19 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Miracle Ridge Limestone Company → Rockbridge Stone #2; 1999-07-20 to 2003-10-15; source msha-controller-operator-history
- **controller_controls_mine:** James E  Bryant → Rockbridge Stone #2; 1999-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James E  Bryant → Miracle Ridge Limestone Company; 1999-07-20 to 2003-10-15; source msha-controller-operator-history
- **operator_operates_mine:** Rockbridge Stone Products, Inc. → Rockbridge Stone #2; 2003-10-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy D  Simmons Jr → Rockbridge Stone Products, Inc.; 2003-10-16 to current/open; source msha-controller-operator-history