# Relationship history for MSHA mine 1516694

Current hierarchy: **Grider Hilda → Hil Don Corp → HIL-DON CORP.**

- 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:** Hil Don Corp → HIL-DON CORP.; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Grider Hilda → HIL-DON CORP.; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Grider Hilda → Hil Don Corp; 1989-08-01 to current/open; source msha-controller-operator-history