# Relationship history for MSHA mine 4605357

Current hierarchy: **Kerstan Corp → Kerstan Corp → Kerstan No 1**

- 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:** Cherry Ridge Corp → Kerstan No 1; 1976-11-11 to 1978-04-23; source msha-controller-operator-history
- **controller_controls_mine:** Stagen Frank → Kerstan No 1; 1976-11-11 to 1978-04-23; source msha-controller-operator-history
- **controller_controls_operator:** Stagen Frank → Cherry Ridge Corp; 1976-11-11 to 1978-04-23; source msha-controller-operator-history
- **operator_operates_mine:** Kerstan Corp → Kerstan No 1; 1978-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kerstan Corp → Kerstan No 1; 1978-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kerstan Corp → Kerstan Corp; 1978-04-24 to current/open; source msha-controller-operator-history