# Relationship history for MSHA mine 4102318

Current hierarchy: **Mcp Industries Inc → Mission Clay Products Corp → Mission Clay Pits**

- 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:** W S Dickey Clay Manufacturing Company → Mission Clay Pits; 1950-01-01 to 1987-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Hepworth Plc → Mission Clay Pits; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hepworth Plc → W S Dickey Clay Manufacturing Company; 1950-01-01 to 1987-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Mission Clay Products Corp → Mission Clay Pits; 1987-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mcp Industries Inc → Mission Clay Pits; 1987-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mcp Industries Inc → Mission Clay Products Corp; 1987-10-01 to current/open; source msha-controller-operator-history