# Relationship history for MSHA mine 4002196

Current hierarchy: **Fischer Howard M Sr → Howard M Fischer Company → King Hill Mill**

- 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:** New Jersey Zinc Company → King Hill Mill; 1950-01-01 to 1989-01-19; source msha-controller-operator-history
- **controller_controls_mine:** Gulf + Western Industries Inc → King Hill Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gulf + Western Industries Inc → New Jersey Zinc Company; 1950-01-01 to 1989-01-19; source msha-controller-operator-history
- **operator_operates_mine:** Howard M Fischer Company → King Hill Mill; 1989-01-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fischer Howard M Sr → King Hill Mill; 1989-01-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fischer Howard M Sr → Howard M Fischer Company; 1989-01-20 to current/open; source msha-controller-operator-history