# Relationship history for MSHA mine 1700898

Current hierarchy: **Howard L  Patten → H.L. Patten Construction Co. Inc. → Sandvik QE340 Screen**

- 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:** H.L. Patten Construction Co. Inc. → Sandvik QE340 Screen; 2012-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Howard L  Patten → Sandvik QE340 Screen; 2012-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard L  Patten → H.L. Patten Construction Co. Inc.; 2012-07-19 to current/open; source msha-controller-operator-history