# Relationship history for MSHA mine 2102536

Current hierarchy: **Glenn  Witham → Witham Concrete Products Inc → WITHAM PIT & MILL**

- 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:** F M Snyker Sand & Gravel → WITHAM PIT & MILL; 1950-01-01 to 1978-08-24; source msha-controller-operator-history
- **controller_controls_mine:** F M  Snyker → WITHAM PIT & MILL; 1950-01-01 to 1978-08-24; source msha-controller-operator-history
- **controller_controls_operator:** F M  Snyker → F M Snyker Sand & Gravel; 1950-01-01 to 1978-08-24; source msha-controller-operator-history
- **operator_operates_mine:** Witham Concrete Products Inc → WITHAM PIT & MILL; 1978-08-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Glenn  Witham → WITHAM PIT & MILL; 1978-08-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Glenn  Witham → Witham Concrete Products Inc; 1978-08-25 to current/open; source msha-controller-operator-history