# Relationship history for MSHA mine 0503626

Current hierarchy: **Shelton Stanley E → Castle Rock Aggregates → A & M Mine**

- 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:** Castle Rock Sand & Gravel → A & M Mine; 1980-11-01 to 1982-10-28; source msha-controller-operator-history
- **controller_controls_mine:** Castle Rock Sand & Gravel → A & M Mine; 1980-11-01 to 1982-10-28; source msha-controller-operator-history
- **controller_controls_operator:** Castle Rock Sand & Gravel → Castle Rock Sand & Gravel; 1980-11-01 to 1982-10-28; source msha-controller-operator-history
- **operator_operates_mine:** Castle Rock Aggregates → A & M Mine; 1982-10-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Shelton Stanley E → A & M Mine; 1982-10-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shelton Stanley E → Castle Rock Aggregates; 1982-10-29 to current/open; source msha-controller-operator-history