# Relationship history for MSHA mine 4404537

Current hierarchy: **Gulf + Western Industries Inc & Raven Smokeless Co → Raven Anchor Smokeless Coal Company → Anchor Strip No 1**

- 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:** Raven Anchor Smokeless Coal Company → Anchor Strip No 1; 1976-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gulf + Western Industries Inc & Raven Smokeless Co → Anchor Strip No 1; 1976-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gulf + Western Industries Inc & Raven Smokeless Co → Raven Anchor Smokeless Coal Company; 1976-09-01 to current/open; source msha-controller-operator-history