# Relationship history for MSHA mine 1103181

Current hierarchy: **Wayne V  Fischer; Joe L.  Fischer → Fischer Excavating Inc → Fischer Sand Plant**

- 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:** Joe L.  Fischer et al → Fischer Sand Plant; 1998-02-10 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Fischer Excavating Inc → Fischer Sand Plant; 2007-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joe L.  Fischer et al → Fischer Excavating Inc; 2007-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wayne V  Fischer et al → Fischer Excavating Inc; 2007-09-10 to current/open; source msha-controller-operator-history