# Relationship history for MSHA mine 4608191

Current hierarchy: **Jack L  Williams → Williams Construction Company → Ansted Surface**

- 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:** Jack L  Williams → Ansted Surface; 1990-12-19 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Williams Construction Company → Ansted Surface; 1992-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jack L  Williams → Williams Construction Company; 1992-06-01 to current/open; source msha-controller-operator-history