# Relationship history for MSHA mine 2602724

Current hierarchy: **Universal Fluids LLC → Drilling Minerals Industries, LLC → DMI Osino Barite Mill**

- 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:** National Oilwell Varco Inc → DMI Osino Barite Mill; 2009-07-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** National Oilwell Varco LP → DMI Osino Barite Mill; 2012-11-29 to 2021-08-31; source msha-controller-operator-history
- **controller_controls_operator:** National Oilwell Varco Inc → National Oilwell Varco LP; 2012-11-29 to 2021-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Drilling Minerals Industries, LLC → DMI Osino Barite Mill; 2021-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Universal Fluids LLC → DMI Osino Barite Mill; 2021-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Universal Fluids LLC → Drilling Minerals Industries, LLC; 2021-09-01 to current/open; source msha-controller-operator-history