# Relationship history for MSHA mine 4100242

Current hierarchy: **Berkshire Hathaway Inc → Acme Brick Company → GARRISON 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Acme Brick Company → GARRISON PIT & PLANT; 1950-01-01 to 2000-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Justin Industries Inc → GARRISON PIT & PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justin Industries Inc → Acme Brick Company; 1950-01-01 to 2000-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Berkshire Hathaway Inc → GARRISON PIT & PLANT; 2000-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Acme Brick Company → GARRISON PIT & PLANT; 2000-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Berkshire Hathaway Inc → Acme Brick Company; 2000-08-01 to current/open; source msha-controller-operator-history