# Relationship history for MSHA mine 4003559

Current hierarchy: **Dustin R  Walker; Billy R  Walker → WALKER STONE LLC → WALKER STONE 2 LLC**

- 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:** Walker Stone LLC → WALKER STONE 2 LLC; 2021-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Billy R  Walker et al → WALKER STONE 2 LLC; 2021-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Billy R  Walker et al → Walker Stone LLC; 2021-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dustin R  Walker et al → Walker Stone LLC; 2021-07-28 to current/open; source msha-controller-operator-history