# Relationship history for MSHA mine 2300133

Current hierarchy: **Smashey Francis W → Hannibal Rock Company → Hannibal Rock Company**

- 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:** Calcium Carbonate Company → Hannibal Rock Company; 1950-01-01 to 1984-07-30; source msha-controller-operator-history
- **controller_controls_mine:** J M Huber Corp → Hannibal Rock Company; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** J M Huber Corp → Calcium Carbonate Company; 1950-01-01 to 1984-07-30; source msha-controller-operator-history
- **operator_operates_mine:** Hannibal Rock Company → Hannibal Rock Company; 1984-07-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smashey Francis W → Hannibal Rock Company; 1984-07-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smashey Francis W → Hannibal Rock Company; 1984-07-31 to current/open; source msha-controller-operator-history