# Relationship history for MSHA mine 4103562

Current hierarchy: **Bill  Mezger; Ben  Goodwin → Mezger Enterprises Ltd → Gene Swenson Quarries**

- 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:** Mezger Enterprises Ltd → Gene Swenson Quarries; 1989-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bill  Mezger  et al → Gene Swenson Quarries; 2002-03-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bill  Mezger  et al → Mezger Enterprises Ltd; 2002-03-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ben  Goodwin  et al → Mezger Enterprises Ltd; 2002-03-18 to current/open; source msha-controller-operator-history