# Relationship history for MSHA mine 2103166

Current hierarchy: **Sharron  Olberg; Jeffrey  Olberg → M & J Construction of Holt, Inc. → Jeff's Plant**

- 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:** Myron  Olberg → Jeff's Plant; 1987-06-18 to 2013-10-20; source msha-controller-operator-history
- **operator_operates_mine:** M & J Construction of Holt, Inc. → Jeff's Plant; 1998-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Myron  Olberg → M & J Construction of Holt, Inc.; 1998-06-01 to 2013-10-20; source msha-controller-operator-history
- **controller_controls_mine:** Sharron  Olberg et al → Jeff's Plant; 2013-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sharron  Olberg et al → M & J Construction of Holt, Inc.; 2013-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jeffrey  Olberg et al → M & J Construction of Holt, Inc.; 2013-10-21 to current/open; source msha-controller-operator-history