# Relationship history for MSHA mine 1201792

Current hierarchy: **Robinson Construction → B & R Enterprises-Div/Robinson Construction → B And R Enterprises**

- 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:** B & R Enterprises-Div/Robinson Construction → B And R Enterprises; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robinson Construction → B And R Enterprises; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robinson Construction → B & R Enterprises-Div/Robinson Construction; 1980-06-01 to current/open; source msha-controller-operator-history