# Relationship history for MSHA mine 3303837

Current hierarchy: **Holmes Limestone → Holmes Limestone Company → Preparation Plant Div**

- 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

- **controller_controls_mine:** Holmes Limestone → Preparation Plant Div; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Holmes Limestone Company → Preparation Plant Div; 1980-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holmes Limestone → Holmes Limestone Company; 1980-10-01 to current/open; source msha-controller-operator-history