# Relationship history for MSHA mine 2302326

Current hierarchy: **Markel D  Scowden; Roy E  Ward → Stone Age Materials → Stone Age Materials**

- 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:** Stone Age Materials → Stone Age Materials; 2006-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy E  Ward et al → Stone Age Materials; 2006-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy E  Ward et al → Stone Age Materials; 2006-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Markel D  Scowden et al → Stone Age Materials; 2006-01-10 to current/open; source msha-controller-operator-history