# Relationship history for MSHA mine 4000866

Current hierarchy: **Savage Resources Ltd → Savage Zinc Inc → JEFFERSON CITY 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:** Usx Corp → JEFFERSON CITY MILL; 1950-01-01 to 1989-06-15; source msha-controller-operator-history
- **controller_controls_mine:** USX Corp (United States Steel Corp) → JEFFERSON CITY MILL; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** USX Corp (United States Steel Corp) → Usx Corp; 1950-01-01 to 1989-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Jefferson City Zinc → JEFFERSON CITY MILL; 1989-06-16 to 1994-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Union Miniere S A → JEFFERSON CITY MILL; 1989-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Union Miniere S A → Jefferson City Zinc; 1989-06-16 to 1994-08-14; source msha-controller-operator-history
- **operator_operates_mine:** Savage Zinc Inc → JEFFERSON CITY MILL; 1994-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Savage Resources Ltd → JEFFERSON CITY MILL; 1994-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Savage Resources Ltd → Savage Zinc Inc; 1994-08-15 to current/open; source msha-controller-operator-history