# Relationship history for MSHA mine 3500710

Current hierarchy: **Allen Ted & John Sigurdson → Ontario Redi-Mix → Ontario Redi-Mix 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Monroc Inc → Ontario Redi-Mix Pit; 1950-01-01 to 1983-09-12; source msha-controller-operator-history
- **controller_controls_mine:** Wel-Com Financial Services & M-K Holding Corp → Ontario Redi-Mix Pit; 1950-01-01 to 2000-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Wel-Com Financial Services & M-K Holding Corp → Monroc Inc; 1950-01-01 to 1983-09-12; source msha-controller-operator-history
- **operator_operates_mine:** Ontario Redi-Mix → Ontario Redi-Mix Pit; 1983-09-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Allen Ted & John Sigurdson Et Al → Ontario Redi-Mix Pit; 1983-09-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Allen Ted & John Sigurdson Et Al → Ontario Redi-Mix; 1983-09-13 to current/open; source msha-controller-operator-history