# Relationship history for MSHA mine 2601977

Current hierarchy: **Aldo R  DiNardo → Royal Cement Company Inc → ROYAL CEMENT COMPANY, INC.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Royal Cement Company Inc → ROYAL CEMENT COMPANY, INC.; 1986-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Aldo R  DiNardo → ROYAL CEMENT COMPANY, INC.; 1986-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Aldo R  DiNardo → Royal Cement Company Inc; 1986-09-01 to current/open; source msha-controller-operator-history