# Relationship history for MSHA mine 3606474

Current hierarchy: **Stanford Energy → Doverspike Brothers Coal Company → Dora Prep Plant**

- 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

- **controller_controls_mine:** Zapata Corp → Dora Prep Plant; 1976-01-10 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Doverspike Brothers Coal Company → Dora Prep Plant; 1977-08-01 to 1983-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Zapata Corp → Doverspike Brothers Coal Company; 1977-08-01 to 1983-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Doverspike Brothers Coal Company → Dora Prep Plant; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stanford Energy → Dora Prep Plant; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stanford Energy → Doverspike Brothers Coal Company; 1983-07-01 to current/open; source msha-controller-operator-history