# Relationship history for MSHA mine 0504913

Current hierarchy: **Alan E  Chiles → Rimrock Exploration and Development, Inc. → Prince Albert**

- 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:** Rimrock Exploration and Development Inc. → Prince Albert; 2008-07-14 to 2009-11-05; source msha-controller-operator-history
- **controller_controls_mine:** Alan E  Chiles → Prince Albert; 2008-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alan E  Chiles → Rimrock Exploration and Development Inc.; 2008-07-14 to 2009-11-05; source msha-controller-operator-history
- **operator_operates_mine:** Hemphill Mining → Prince Albert; 2009-11-06 to 2010-09-13; source msha-controller-operator-history
- **controller_controls_mine:** William S  Hemphill et al → Prince Albert; 2009-11-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William S  Hemphill et al → Hemphill Mining; 2009-11-06 to 2010-09-13; source msha-controller-operator-history
- **controller_controls_operator:** Mindy M  Hemphill et al → Hemphill Mining; 2009-11-06 to 2010-09-13; source msha-controller-operator-history
- **operator_operates_mine:** Rimrock Exploration and Development, Inc. → Prince Albert; 2010-09-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alan E  Chiles → Rimrock Exploration and Development, Inc.; 2010-09-14 to current/open; source msha-controller-operator-history