# Relationship history for MSHA mine 4801821

Current hierarchy: **Jacob J Tyra; Graham H Jacobs → TommyKnockers LLC → Iron Duke**

- 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:** TommyKnockers LLC → Iron Duke; 2018-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Graham H Jacobs et al → Iron Duke; 2018-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Graham H Jacobs et al → TommyKnockers LLC; 2018-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jacob J Tyra et al → TommyKnockers LLC; 2018-11-01 to current/open; source msha-controller-operator-history