# Relationship history for MSHA mine 3401387

Current hierarchy: **Howard  Mattox → Haskell County Gravel Company Inc → Haskell County Pit & Plant**

- 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

- **operator_operates_mine:** Haskell County Gravel Company Inc → Haskell County Pit & Plant; 1983-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Howard  Mattox et al → Haskell County Pit & Plant; 1983-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard  Mattox et al → Haskell County Gravel Company Inc; 1983-02-01 to current/open; source msha-controller-operator-history