# Relationship history for MSHA mine 3609269

Current hierarchy: **Hannah L  Robinson → H.L. Robinson Sand and Gravel → Fallon Stone Quarry**

- 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

- **controller_controls_mine:** Hannah L  Robinson → Fallon Stone Quarry; 1988-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Timber Lane Stone Inc. → Fallon Stone Quarry; 2004-07-27 to 2012-01-05; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Keller → Fallon Stone Quarry; 2004-07-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Keller → Timber Lane Stone Inc.; 2004-07-27 to 2012-01-05; source msha-controller-operator-history
- **operator_operates_mine:** H.L. Robinson Sand and Gravel → Fallon Stone Quarry; 2012-01-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hannah L  Robinson → H.L. Robinson Sand and Gravel; 2012-01-06 to current/open; source msha-controller-operator-history