# Relationship history for MSHA mine 4607859

Current hierarchy: **Delta Industries Inc → Delta Mining Inc → Mary Lynn #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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Delta Industries Inc → Mary Lynn #1; 1972-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Mary Lynn #1; 1988-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Perrine Robert F → Mary Lynn #1; 1988-12-01 to 1990-12-11; source msha-controller-operator-history
- **operator_operates_mine:** R F P Inc → Mary Lynn #1; 1990-03-01 to 1990-12-11; source msha-controller-operator-history
- **controller_controls_operator:** Perrine Robert F → R F P Inc; 1990-03-01 to 1990-12-11; source msha-controller-operator-history
- **operator_operates_mine:** Bentley Coal Company → Mary Lynn #1; 1990-12-12 to 1991-09-11; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Bentley Coal Company; 1990-12-12 to 1991-09-11; source msha-controller-operator-history
- **operator_operates_mine:** Delta Mining Inc → Mary Lynn #1; 1991-09-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Delta Industries Inc → Delta Mining Inc; 1991-09-12 to current/open; source msha-controller-operator-history