# Relationship history for MSHA mine 4103288

Current hierarchy: **Seidel Alton F → Seidel Inc → Portable Plant & 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Cal-Con Materials → Portable Plant & Pits; 1985-02-01 to 1985-07-16; source msha-controller-operator-history
- **controller_controls_mine:** Hanks M C → Portable Plant & Pits; 1985-02-01 to 1985-07-16; source msha-controller-operator-history
- **controller_controls_operator:** Hanks M C → Cal-Con Materials; 1985-02-01 to 1985-07-16; source msha-controller-operator-history
- **controller_controls_mine:** Seidel Alton F → Portable Plant & Pits; 1985-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Seidel Inc → Portable Plant & Pits; 1985-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Seidel Alton F → Seidel Inc; 1985-07-17 to current/open; source msha-controller-operator-history