# Relationship history for MSHA mine 1516929

Current hierarchy: **Holst William F → Universal Minerals & Mining Corp → Universal Minerals & Mining**

- 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

- **controller_controls_mine:** Holst William F → Universal Minerals & Mining; 1990-03-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Universal Minerals & Mining Corp → Universal Minerals & Mining; 1990-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holst William F → Universal Minerals & Mining Corp; 1990-08-01 to current/open; source msha-controller-operator-history