# Relationship history for MSHA mine 0103521

Current hierarchy: **Alfredo C  Martinez; Blanca  Aguilar → Fred & B Stone → Fred & B Stone**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Fred & B Stone → Fred & B Stone; 2018-05-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Blanca  Aguilar et al → Fred & B Stone; 2018-05-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Blanca  Aguilar et al → Fred & B Stone; 2018-05-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alfredo C  Martinez et al → Fred & B Stone; 2018-05-15 to current/open; source msha-controller-operator-history