# Relationship history for MSHA mine 3304316

Current hierarchy: **Jon P Thompson; Roy  Thompson → Letart Corp → Letart Corporation #4**

- 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:** Jon P Thompson et al → Letart Corporation #4; 1987-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Letart Corp → Letart Corporation #4; 1993-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jon P Thompson et al → Letart Corp; 1993-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy  Thompson et al → Letart Corp; 1993-11-01 to current/open; source msha-controller-operator-history