# Relationship history for MSHA mine 0500891

Current hierarchy: **Mendisco Mark & Marce → Mendisco Mining → Duggan Adit**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Kelmine Corp → Duggan Adit; 1950-01-01 to 1987-02-11; source msha-controller-operator-history
- **controller_controls_mine:** Colorado Kenworth Inc → Duggan Adit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Colorado Kenworth Inc → Kelmine Corp; 1950-01-01 to 1987-02-11; source msha-controller-operator-history
- **operator_operates_mine:** Mendisco Mining → Duggan Adit; 1987-02-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mendisco Mark & Marce → Duggan Adit; 1987-02-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mendisco Mark & Marce → Mendisco Mining; 1987-02-12 to current/open; source msha-controller-operator-history