# Relationship history for MSHA mine 4103465

Current hierarchy: **Tyler Sand Company → Tyler Sand Company → Tyler Plant**

- 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:** Tyler Sand Company → Tyler Plant; 1987-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tyler Sand Company → Tyler Plant; 1987-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tyler Sand Company → Tyler Sand Company; 1987-05-01 to current/open; source msha-controller-operator-history