# Relationship history for MSHA mine 1518962

Current hierarchy: **Justin L  Curry → Big Branch Energy Inc → Bobs Creek Strip**

- 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:** Spark Energy, Inc. → Bobs Creek Strip; 2006-01-18 to 2006-11-09; source msha-controller-operator-history
- **controller_controls_mine:** Clark  Middleton → Bobs Creek Strip; 2006-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clark  Middleton → Spark Energy, Inc.; 2006-01-18 to 2006-11-09; source msha-controller-operator-history
- **operator_operates_mine:** Big Branch Energy Inc → Bobs Creek Strip; 2006-11-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Justin L  Curry → Bobs Creek Strip; 2006-11-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justin L  Curry → Big Branch Energy Inc; 2006-11-10 to current/open; source msha-controller-operator-history