# Relationship history for MSHA mine 3605521

Current hierarchy: **Mazzarella Richard-Fred & Michael → Mazzarella Coal Company → Migyanka Strip**

- 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:** James H Bender Inc → Migyanka Strip; 1975-03-01 to 1977-10-14; source msha-controller-operator-history
- **controller_controls_mine:** Bender James H → Migyanka Strip; 1975-03-01 to 1977-10-14; source msha-controller-operator-history
- **controller_controls_operator:** Bender James H → James H Bender Inc; 1975-03-01 to 1977-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Mazzarella Coal Company → Migyanka Strip; 1977-10-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mazzarella Richard-Fred & Michael → Migyanka Strip; 1977-10-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mazzarella Richard-Fred & Michael → Mazzarella Coal Company; 1977-10-15 to current/open; source msha-controller-operator-history