# Relationship history for MSHA mine 2501050

Current hierarchy: **Don  Rogert → Mallard Sand & Gravel Company → RIHA PIT #3**

- 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:** City Wide Rock & Excavating Inc → RIHA PIT #3; 1981-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** City Wide Sand & Gravel Inc → RIHA PIT #3; 1985-09-01 to 1993-08-12; source msha-controller-operator-history
- **controller_controls_operator:** City Wide Rock & Excavating Inc → City Wide Sand & Gravel Inc; 1985-09-01 to 1993-08-12; source msha-controller-operator-history
- **operator_operates_mine:** Mallard Sand & Gravel Company → RIHA PIT #3; 1993-08-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Don  Rogert → RIHA PIT #3; 1993-08-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Don  Rogert → Mallard Sand & Gravel Company; 1993-08-13 to current/open; source msha-controller-operator-history