# Relationship history for MSHA mine 3609412

Current hierarchy: **Dave B  Barnes → Dave Barnes → Leykamm Quarry**

- 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:** D B S P → Leykamm Quarry; 2006-01-20 to 2008-04-06; source msha-controller-operator-history
- **controller_controls_mine:** Daniel W  Barnes → Leykamm Quarry; 2006-01-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniel W  Barnes → D B S P; 2006-01-20 to 2008-04-06; source msha-controller-operator-history
- **operator_operates_mine:** Dave Barnes → Leykamm Quarry; 2008-04-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dave B  Barnes → Leykamm Quarry; 2008-04-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dave B  Barnes → Dave Barnes; 2008-04-07 to current/open; source msha-controller-operator-history