# Relationship history for MSHA mine 4003092

Current hierarchy: **National Coal Corporation → National Coal Corporation → Mine No 6**

- 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

- **operator_operates_mine:** U S Coal Inc → Mine No 6; 1996-04-01 to 2004-04-16; source msha-controller-operator-history
- **controller_controls_mine:** William M  Bale → Mine No 6; 2001-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William M  Bale → U S Coal Inc; 2001-04-01 to 2004-04-16; source msha-controller-operator-history
- **controller_controls_mine:** National Coal Corporation → Mine No 6; 2003-05-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** National Coal Corporation → Mine No 6; 2004-04-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** National Coal Corporation → National Coal Corporation; 2004-04-17 to current/open; source msha-controller-operator-history