# Relationship history for MSHA mine 4100368

Current hierarchy: **Berkshire Hathaway Inc → Acme Brick Company → Denton Pits**

- 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 → Denton Pits; 1950-01-01 to 2000-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Justin Industries Inc → Denton Pits; 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 → Denton Pits; 2000-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Acme Building Brands → Denton Pits; 2000-08-01 to 2001-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Berkshire Hathaway Inc → Denton Pits; 2000-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Berkshire Hathaway Inc → Acme Building Brands; 2000-08-01 to 2001-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Acme Brick Company → Denton Pits; 2002-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Berkshire Hathaway Inc → Acme Brick Company; 2002-01-01 to current/open; source msha-controller-operator-history