# Relationship history for MSHA mine 1302239

Current hierarchy: **Robert J  Hamilton; John R  Hamilton → Greene County Redi-Mix Inc → ARMSTRONG PIT**

- 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:** John  Hamilton → ARMSTRONG PIT; 1980-04-30 to 2014-09-29; source msha-controller-operator-history
- **operator_operates_mine:** Greene County Redi-Mix Inc → ARMSTRONG PIT; 2000-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Hamilton → Greene County Redi-Mix Inc; 2000-01-01 to 2014-09-29; source msha-controller-operator-history
- **controller_controls_mine:** Robert J  Hamilton et al → ARMSTRONG PIT; 2014-09-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert J  Hamilton et al → Greene County Redi-Mix Inc; 2014-09-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John R  Hamilton et al → Greene County Redi-Mix Inc; 2014-09-30 to current/open; source msha-controller-operator-history