# Relationship history for MSHA mine 1518350

Current hierarchy: **John  Harris → Berkeley Energy Corporation → No 1 Mine**

- 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

- **controller_controls_mine:** John  Harris → No 1 Mine; 1995-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Berkeley Energy Corporation → No 1 Mine; 2001-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Harris → Berkeley Energy Corporation; 2001-03-01 to current/open; source msha-controller-operator-history