# Relationship history for MSHA mine 0600353

Current hierarchy: **Kenneth W  Kovacs → Dbd Inc → Sandcut Mine**

- 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:** Federal Sand & Gravel Inc → Sandcut Mine; 1950-01-01 to 1981-05-25; source msha-controller-operator-history
- **controller_controls_mine:** Kovacs E Paul → Sandcut Mine; 1950-01-01 to 1981-05-25; source msha-controller-operator-history
- **controller_controls_operator:** Kovacs E Paul → Federal Sand & Gravel Inc; 1950-01-01 to 1981-05-25; source msha-controller-operator-history
- **operator_operates_mine:** Dbd Inc → Sandcut Mine; 1981-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kenneth W  Kovacs → Sandcut Mine; 1981-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kenneth W  Kovacs → Dbd Inc; 1981-05-26 to current/open; source msha-controller-operator-history