# Relationship history for MSHA mine 3901484

Current hierarchy: **Justin  Higman → Higman Sand & Gravel, Inc. → Higman No. 4**

- 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:** Justin  Higman et al → Higman No. 4; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Higman Sand & Gravel, Inc. → Higman No. 4; 2003-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justin  Higman et al → Higman Sand & Gravel, Inc.; 2003-05-12 to current/open; source msha-controller-operator-history