# Relationship history for MSHA mine 2300553

Current hierarchy: **Hill Robert → Extender Products Limited → Mineral Point Plant**

- 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:** Milchem Inc → Mineral Point Plant; 1950-01-01 to 1986-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Baker Hughes Inc → Mineral Point Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Baker Hughes Inc → Milchem Inc; 1950-01-01 to 1986-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Extender Products Limited → Mineral Point Plant; 1986-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hill Robert → Mineral Point Plant; 1986-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hill Robert → Extender Products Limited; 1986-04-01 to current/open; source msha-controller-operator-history