# Relationship history for MSHA mine 4602620

Current hierarchy: **James H  Atkinson → Bridgeport Mining Company → Ryder No 1 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** James H  Atkinson → Ryder No 1 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lecco Inc → Ryder No 1 Strip; 1950-01-01 to 1977-04-03; source msha-controller-operator-history
- **controller_controls_mine:** Cleghorn Robert B Jr → Ryder No 1 Strip; 1950-01-01 to 1984-07-08; source msha-controller-operator-history
- **controller_controls_operator:** Cleghorn Robert B Jr → Lecco Inc; 1950-01-01 to 1977-04-03; source msha-controller-operator-history
- **operator_operates_mine:** Bridgeport Mining Company → Ryder No 1 Strip; 1977-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James H  Atkinson → Bridgeport Mining Company; 1977-04-04 to current/open; source msha-controller-operator-history