# Relationship history for MSHA mine 1508616

Current hierarchy: **Greer Warren → Melco Coal Company → No 1 Surface**

- 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:** Greer Warren Et Al → No 1 Surface; 1974-10-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Melco Coal Company → No 1 Surface; 1975-08-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greer Warren Et Al → Melco Coal Company; 1975-08-08 to current/open; source msha-controller-operator-history