# Relationship history for MSHA mine 2901896

Current hierarchy: **Drake Donald F & Jo M → Draco Gypsum → Medicine Man**

- 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:** Draco Gypsum → Medicine Man; 1983-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Drake Donald F & Jo M → Medicine Man; 1983-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Drake Donald F & Jo M → Draco Gypsum; 1983-01-01 to current/open; source msha-controller-operator-history