# Relationship history for MSHA mine 0301729

Current hierarchy: **Mills Melinda → Dirtco Inc → DIRTCO INC**

- 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:** Dirtco Inc → DIRTCO INC; 1992-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mills Melinda → DIRTCO INC; 1992-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mills Melinda → Dirtco Inc; 1992-03-01 to current/open; source msha-controller-operator-history