# Relationship history for MSHA mine 0800977

Current hierarchy: **Hendrickson Edward G Jr → Gulf Shore Seafood Inc → Frisch Pit**

- 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:** Hendrickson Edward G Jr → Frisch Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bob Rigby Inc → Frisch Pit; 1980-12-01 to 1984-10-22; source msha-controller-operator-history
- **controller_controls_mine:** Rigby Bob → Frisch Pit; 1980-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rigby Bob → Bob Rigby Inc; 1980-12-01 to 1984-10-22; source msha-controller-operator-history
- **operator_operates_mine:** Gulf Shore Seafood Inc → Frisch Pit; 1984-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hendrickson Edward G Jr → Gulf Shore Seafood Inc; 1984-10-23 to current/open; source msha-controller-operator-history