# Relationship history for MSHA mine 3304339

Current hierarchy: **Stephen  Varkony; William M  Varkony → Varkony Mining Company → Oberlin Mine**

- 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:** William M  Varkony et al → Oberlin Mine; 1974-08-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Varkony Mining Company → Oberlin Mine; 1994-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William M  Varkony et al → Varkony Mining Company; 1994-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stephen  Varkony et al → Varkony Mining Company; 1994-09-01 to current/open; source msha-controller-operator-history