# Relationship history for MSHA mine 2101861

Current hierarchy: **Jeff A  Carlson → Ulland Brothers Inc → Anchor Lake Pit**

- 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:** Orlin L  Ofstad et al → Anchor Lake Pit; 1950-01-01 to 2020-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Ulland Brothers Inc → Anchor Lake Pit; 1981-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Orlin L  Ofstad et al → Ulland Brothers Inc; 1981-06-01 to 2020-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Jeff A  Carlson → Anchor Lake Pit; 2021-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jeff A  Carlson → Ulland Brothers Inc; 2021-01-01 to current/open; source msha-controller-operator-history