# Relationship history for MSHA mine 1901137

Current hierarchy: **Louise  Landers → P A Landers Inc → Hart-L Crusher**

- 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:** Louise  Landers et al → Hart-L Crusher; 1988-07-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** P A Landers Inc → Hart-L Crusher; 2004-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Louise  Landers et al → P A Landers Inc; 2004-04-01 to current/open; source msha-controller-operator-history