# Relationship history for MSHA mine 3606311

Current hierarchy: **Schomaker Richard C → West Penn Tipple Company Inc → West Penn Tipple Company Incorporated Ii**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** North Butler Coal Company → West Penn Tipple Company Incorporated Ii; 1977-01-11 to 1979-10-15; source msha-controller-operator-history
- **controller_controls_mine:** Conterno David & Angeline → West Penn Tipple Company Incorporated Ii; 1977-01-11 to 1979-10-15; source msha-controller-operator-history
- **controller_controls_operator:** Conterno David & Angeline → North Butler Coal Company; 1977-01-11 to 1979-10-15; source msha-controller-operator-history
- **controller_controls_mine:** Schomaker Richard C → West Penn Tipple Company Incorporated Ii; 1977-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** West Penn Tipple Company Inc → West Penn Tipple Company Incorporated Ii; 1979-10-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Schomaker Richard C → West Penn Tipple Company Inc; 1979-10-16 to current/open; source msha-controller-operator-history