# Relationship history for MSHA mine 2900470

Current hierarchy: **Donnie N  Hobbs → Hobbs Quality Service → Hobbs Quality Service**

- 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:** O'Kelley Sand & Gravel Inc → Hobbs Quality Service; 1950-01-01 to 2012-07-01; source msha-controller-operator-history
- **controller_controls_mine:** Edwin D  O'Kelley → Hobbs Quality Service; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Edwin D  O'Kelley → O'Kelley Sand & Gravel Inc; 1950-01-01 to 2012-07-01; source msha-controller-operator-history
- **controller_controls_mine:** David  Baeza → Hobbs Quality Service; 2007-04-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hobbs Brothers, Inc. → Hobbs Quality Service; 2012-07-02 to 2019-08-21; source msha-controller-operator-history
- **controller_controls_mine:** Donnie N  Hobbs → Hobbs Quality Service; 2012-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donnie N  Hobbs → Hobbs Brothers, Inc.; 2012-07-02 to 2019-08-21; source msha-controller-operator-history
- **operator_operates_mine:** Desert Valley, Inc. → Hobbs Quality Service; 2019-08-22 to 2025-01-20; source msha-controller-operator-history
- **controller_controls_operator:** David  Baeza → Desert Valley, Inc.; 2019-08-22 to 2025-01-20; source msha-controller-operator-history
- **operator_operates_mine:** Hobbs Quality Service → Hobbs Quality Service; 2025-01-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Donnie N  Hobbs → Hobbs Quality Service; 2025-01-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donnie N  Hobbs → Hobbs Quality Service; 2025-01-21 to current/open; source msha-controller-operator-history