# Relationship history for MSHA mine 1401621

Current hierarchy: **Dane Q Barclay → Alsop Sand Co. Inc. → Osborne Pit**

- 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:** David H  Barclay et al → Osborne Pit; 1950-01-01 to 2017-05-10; source msha-controller-operator-history
- **operator_operates_mine:** Alsop Sand Co. Inc. → Osborne Pit; 2002-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David H  Barclay et al → Alsop Sand Co. Inc.; 2002-08-07 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_operator:** Dane Q  Barclay et al → Alsop Sand Co. Inc.; 2002-08-07 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_mine:** Dane Q Barclay → Osborne Pit; 2017-05-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dane Q Barclay → Alsop Sand Co. Inc.; 2017-05-11 to current/open; source msha-controller-operator-history