# Relationship history for MSHA mine 1516988

Current hierarchy: **Curtis  Hopkins → Black Diamond Processing Inc → Climax #1**

- 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:** Green Pond Ridge Coal Company → Climax #1; 1990-10-01 to 1992-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Cox Willie E → Climax #1; 1990-10-01 to 1992-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Cox Willie E → Green Pond Ridge Coal Company; 1990-10-01 to 1992-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Black Diamond Processing Inc → Climax #1; 1992-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Curtis  Hopkins → Climax #1; 1992-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Curtis  Hopkins → Black Diamond Processing Inc; 1992-12-01 to current/open; source msha-controller-operator-history