# Relationship history for MSHA mine 4300809

Current hierarchy: **Gregory  Markowski → Markowski Excavating, Inc. → PORTABLE CRUSHER #3**

- 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:** Gregory  Markowski et al → PORTABLE CRUSHER #3; 2001-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Markowski Excavating, Inc. → PORTABLE CRUSHER #3; 2022-04-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gregory  Markowski et al → Markowski Excavating, Inc.; 2022-04-08 to current/open; source msha-controller-operator-history