# Relationship history for MSHA mine 4104522

Current hierarchy: **Vic A  Bownds; Cathy  Bownds → Robert McHam LTD → Portable Crusher-XL1500**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Robert McHam LTD → Portable Crusher-XL1500; 2005-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Vic A  Bownds et al → Portable Crusher-XL1500; 2005-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vic A  Bownds et al → Robert McHam LTD; 2005-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cathy  Bownds et al → Robert McHam LTD; 2005-02-21 to current/open; source msha-controller-operator-history