# Relationship history for MSHA mine 2700426

Current hierarchy: **Mark E.  Johnston → Mark Johnston Construction → Brown Lenox Portable Jaw**

- 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:** Mark Johnston Construction → Brown Lenox Portable Jaw; 2007-08-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mark E.  Johnston → Brown Lenox Portable Jaw; 2007-08-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mark E.  Johnston → Mark Johnston Construction; 2007-08-27 to current/open; source msha-controller-operator-history