# Relationship history for MSHA mine 1518926

Current hierarchy: **Rifle Coal Company; Anthony  Frederick → Associated Contracting LLC → Equal Fork 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:** Anthony  Frederick et al → Equal Fork Surface; 2000-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Associated Contracting LLC → Equal Fork Surface; 2005-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anthony  Frederick et al → Associated Contracting LLC; 2005-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rifle Coal Company et al → Associated Contracting LLC; 2005-09-15 to current/open; source msha-controller-operator-history
