# Relationship history for MSHA mine 4202734

Current hierarchy: **Rowland  Yardley; Skylar  Yardley → Yardley Construction → Yardley 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

- **operator_operates_mine:** Yardley Construction → Yardley Pit; 2021-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Skylar  Yardley et al → Yardley Pit; 2021-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Skylar  Yardley et al → Yardley Construction; 2021-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rowland  Yardley et al → Yardley Construction; 2021-12-06 to current/open; source msha-controller-operator-history