# Relationship history for MSHA mine 3503900

Current hierarchy: **Richard  Healey → West Coast Reclamation → Pair-A-Dice**

- 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

- **controller_controls_mine:** Richard  Healey et al → Pair-A-Dice; 2019-10-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** West Coast Reclamation → Pair-A-Dice; 2020-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Healey et al → West Coast Reclamation; 2020-04-14 to current/open; source msha-controller-operator-history