# Relationship history for MSHA mine 3503863

Current hierarchy: **Mary J Northern; Larry E Northern → Northern Rock Supply → Northern Rock Supply**

- 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:** Northern Rock Supply → Northern Rock Supply; 2017-12-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry E Northern et al → Northern Rock Supply; 2017-12-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry E Northern et al → Northern Rock Supply; 2017-12-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mary J Northern et al → Northern Rock Supply; 2017-12-26 to current/open; source msha-controller-operator-history