# Relationship history for MSHA mine 1800358

Current hierarchy: **Maryland Lava Co → Maryland Lava Co → Maryland Lava Co Inc Maryland Lava**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Maryland Lava Co → Maryland Lava Co Inc Maryland Lava; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Maryland Lava Co → Maryland Lava Co Inc Maryland Lava; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Maryland Lava Co → Maryland Lava Co; 1950-01-01 to current/open; source msha-controller-operator-history