# Relationship history for MSHA mine 3604778

Current hierarchy: **Andrew L  Bishop → Wysox Sand and Gravel → Wysox S & G Inc.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Wysox Sand & Gravel Inc → Wysox S & G Inc.; 1950-01-01 to 2012-06-14; source msha-controller-operator-history
- **controller_controls_mine:** Walter  Warburton et al → Wysox S & G Inc.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walter  Warburton et al → Wysox Sand & Gravel Inc; 1950-01-01 to 2012-06-14; source msha-controller-operator-history
- **controller_controls_operator:** Roy  Piper et al → Wysox Sand & Gravel Inc; 1950-01-01 to 2012-06-14; source msha-controller-operator-history
- **operator_operates_mine:** Wysox Sand and Gravel → Wysox S & G Inc.; 2012-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Andrew  Bishop et al → Wysox S & G Inc.; 2012-06-15 to 2015-04-08; source msha-controller-operator-history
- **controller_controls_operator:** Andrew  Bishop et al → Wysox Sand and Gravel; 2012-06-15 to 2015-04-08; source msha-controller-operator-history
- **controller_controls_mine:** Andrew L  Bishop → Wysox S & G Inc.; 2015-04-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Andrew L  Bishop → Wysox Sand and Gravel; 2015-04-09 to current/open; source msha-controller-operator-history