# Relationship history for MSHA mine 2103878

Current hierarchy: **Tim  Ferguson → Ferguson Brothers Excavating Inc. → Ferguson Brothers Excavating Inc Unit 6**

- 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:** Tim  Ferguson → Ferguson Brothers Excavating Inc Unit 6; 2014-04-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ferguson Brothers Excavating Inc. → Ferguson Brothers Excavating Inc Unit 6; 2016-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tim  Ferguson → Ferguson Brothers Excavating Inc.; 2016-03-10 to current/open; source msha-controller-operator-history