# Relationship history for MSHA mine 4300471

Current hierarchy: **Ormond  Bushey Jr → Ormond Bushey & Sons Inc → Portable**

- 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:** Ormond  Bushey Jr → Portable; 1980-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Colton → Portable; 1987-07-24 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** R J Colton Company Inc → Portable; 1991-07-01 to 1998-09-22; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Colton → R J Colton Company Inc; 1991-07-01 to 1998-09-22; source msha-controller-operator-history
- **operator_operates_mine:** Ormond Bushey & Sons Inc → Portable; 1998-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ormond  Bushey Jr → Ormond Bushey & Sons Inc; 1998-09-23 to current/open; source msha-controller-operator-history