# Relationship history for MSHA mine 0504867

Current hierarchy: **Skanska AB → Skanska USA Civil West RMD → Nordberg Assembly**

- 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:** Skanska AB → Nordberg Assembly; 2001-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Skanska USA Civil West RMD → Nordberg Assembly; 2007-05-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Skanska AB → Skanska USA Civil West RMD; 2007-05-03 to current/open; source msha-controller-operator-history