# Relationship history for MSHA mine 2104120

Current hierarchy: **John A.  Fritz → Fritz Companies LLC → Power Screen 2**

- 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 A.  Fritz → Power Screen 2; 2023-09-06 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Fritz Companies LLC → Power Screen 2; 2026-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John A.  Fritz → Fritz Companies LLC; 2026-06-15 to current/open; source msha-controller-operator-history