# Relationship history for MSHA mine 0300608

Current hierarchy: **Lorre  Moore Parrish; Tera M  Harper → Sheridan White Rock Inc. → Skorcz Pit & 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Sheridan White Rock Company → Skorcz Pit & Plant; 1950-01-01 to 2009-11-18; source msha-controller-operator-history
- **controller_controls_mine:** Terry D  Moore → Skorcz Pit & Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Terry D  Moore → Sheridan White Rock Company; 1950-01-01 to 2009-11-18; source msha-controller-operator-history
- **operator_operates_mine:** Sheridan White Rock Inc. → Skorcz Pit & Plant; 2009-11-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tera M  Harper et al → Skorcz Pit & Plant; 2009-11-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tera M  Harper et al → Sheridan White Rock Inc.; 2009-11-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lorre  Moore Parrish et al → Sheridan White Rock Inc.; 2009-11-19 to current/open; source msha-controller-operator-history