# Relationship history for MSHA mine 3609455

Current hierarchy: **Stanley M  Stanchick; Sheldon A  Derck → SMC Coal Company → SMC Coal Co.**

- 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:** SMC Coal Company → SMC Coal Co.; 2006-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stanley M  Stanchick et al → SMC Coal Co.; 2006-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stanley M  Stanchick et al → SMC Coal Company; 2006-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sheldon A  Derck et al → SMC Coal Company; 2006-07-26 to current/open; source msha-controller-operator-history