# Relationship history for MSHA mine 3002953

Current hierarchy: **Hubbard Daniel → Hubbard Sand & Gravel East Ltd → HUBBARD SAND & GRAVEL EAST, LTD**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Hubbard Sand & Gravel East Ltd → HUBBARD SAND & GRAVEL EAST, LTD; 1990-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hubbard Daniel → HUBBARD SAND & GRAVEL EAST, LTD; 1990-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hubbard Daniel → Hubbard Sand & Gravel East Ltd; 1990-04-01 to current/open; source msha-controller-operator-history