# Relationship history for MSHA mine 2801027

Current hierarchy: **John L  Silvi; Laurence J  Silvi II → Gibraltar Rock Inc T-A Gibraltar Rock , Belle Mead → Belle Mead**

- 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:** Gibraltar Rock Inc T-A Gibraltar Rock , Belle Mead → Belle Mead; 2009-06-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Laurence J  Silvi II  Et Al → Belle Mead; 2009-06-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Laurence J  Silvi II  Et Al → Gibraltar Rock Inc T-A Gibraltar Rock , Belle Mead; 2009-06-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John L  Silvi  Et Al → Gibraltar Rock Inc T-A Gibraltar Rock , Belle Mead; 2009-06-22 to current/open; source msha-controller-operator-history