# Relationship history for MSHA mine 4503534

Current hierarchy: **Lawrence  Sali; Steve  Sali → Columbia Ready-Mix Inc → Rap Crusher**

- 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:** Lawrence  Sali  et al → Rap Crusher; 1978-08-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Columbia Ready-Mix Inc → Rap Crusher; 2003-03-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lawrence  Sali  et al → Columbia Ready-Mix Inc; 2003-03-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve  Sali  et al → Columbia Ready-Mix Inc; 2003-03-25 to current/open; source msha-controller-operator-history