# Relationship history for MSHA mine 3301514

Current hierarchy: **Robert W  West → Hilltop Aggregate Inc. → HILLTOP AGGREGATE, INC.**

- 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:** Hilltop Sand & Gravel Company → HILLTOP AGGREGATE, INC.; 1950-01-01 to 1983-04-05; source msha-controller-operator-history
- **controller_controls_mine:** C H  Keller → HILLTOP AGGREGATE, INC.; 1950-01-01 to 1983-04-05; source msha-controller-operator-history
- **controller_controls_operator:** C H  Keller → Hilltop Sand & Gravel Company; 1950-01-01 to 1983-04-05; source msha-controller-operator-history
- **operator_operates_mine:** Hilltop Aggregate Inc → HILLTOP AGGREGATE, INC.; 1983-04-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert W  West → HILLTOP AGGREGATE, INC.; 1983-04-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert W  West → Hilltop Aggregate Inc; 1983-04-06 to current/open; source msha-controller-operator-history