# Relationship history for MSHA mine 4407121

Current hierarchy: **David  Stevenson → DaCoal Mining, Inc. → No. 7**

- 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

- **controller_controls_mine:** David  Stevenson → No. 7; 2000-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** DaCoal Mining, Inc. → No. 7; 2004-11-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David  Stevenson → DaCoal Mining, Inc.; 2004-11-29 to current/open; source msha-controller-operator-history