# Relationship history for MSHA mine 1001668

Current hierarchy: **Summit Materials LLC → Kilgore Companies → Gentry Pit**

- 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:** Harold  Elam → Gentry Pit; 1950-01-01 to 2011-03-31; source msha-controller-operator-history
- **controller_controls_mine:** David C  Coats → Gentry Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Triple C Concrete Inc → Gentry Pit; 1985-04-01 to 2011-01-14; source msha-controller-operator-history
- **controller_controls_operator:** David C  Coats → Triple C Concrete Inc; 1985-04-01 to 2011-01-14; source msha-controller-operator-history
- **operator_operates_mine:** Kilgore Companies → Gentry Pit; 2011-01-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harold  Elam → Kilgore Companies; 2011-01-15 to 2011-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Gentry Pit; 2011-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Kilgore Companies; 2011-04-01 to current/open; source msha-controller-operator-history