# Relationship history for MSHA mine 0405987

Current hierarchy: **Vulcan Materials Company → Calmat Co → Cupertino Quarry**

- 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:** Calmat Company → Cupertino Quarry; 1987-11-09 to 1999-01-05; source msha-controller-operator-history
- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Cupertino Quarry; 1999-01-06 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → Cupertino Quarry; 2007-11-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Vulcan Materials Company → Cupertino Quarry; 2025-04-29 to 2025-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Vulcan Materials Company; 2025-04-29 to 2025-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Materials Company; 2025-04-29 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_operator:** Calmat Company → Vulcan Materials Company; 2025-04-29 to 1999-01-05; source msha-controller-operator-history
- **operator_operates_mine:** Calmat Co → Cupertino Quarry; 2025-06-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Calmat Co; 2025-06-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Calmat Co; 2025-06-04 to 2007-11-15; source msha-controller-operator-history