# Relationship history for MSHA mine 4300281

Current hierarchy: **Frank  Whitcomb → Frank W Whitcomb Construction Corp → Blanchard 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:** Frank  Whitcomb → Blanchard Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** John H Blanchard Excavating → Blanchard Pit; 1950-01-01 to 1981-06-15; source msha-controller-operator-history
- **controller_controls_mine:** Blanchard John H → Blanchard Pit; 1950-01-01 to 1981-06-15; source msha-controller-operator-history
- **controller_controls_operator:** Blanchard John H → John H Blanchard Excavating; 1950-01-01 to 1981-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Frank W Whitcomb Construction Corp → Blanchard Pit; 1981-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frank  Whitcomb → Frank W Whitcomb Construction Corp; 1981-06-16 to current/open; source msha-controller-operator-history