# Relationship history for MSHA mine 4503528

Current hierarchy: **Mark  Higgins; Sally  Higgins → B R Rock → B R Rock**

- 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:** B R Rock → B R Rock; 2003-02-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mark  Higgins  et al → B R Rock; 2003-02-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mark  Higgins  et al → B R Rock; 2003-02-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sally  Higgins  et al → B R Rock; 2003-02-04 to current/open; source msha-controller-operator-history