# Relationship history for MSHA mine 2602339

Current hierarchy: **Joseph John B → Mountain America Corp → SNOW WHITE GYPSUM MINE**

- 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:** Mountain America Corp → SNOW WHITE GYPSUM MINE; 1998-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph John B → SNOW WHITE GYPSUM MINE; 1998-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joseph John B → Mountain America Corp; 1998-04-01 to current/open; source msha-controller-operator-history