# Relationship history for MSHA mine 1516799

Current hierarchy: **Tackett Vernon W → Diamond T Coal Corp → No 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

- **controller_controls_mine:** Collins Roger B → No 1; 1974-12-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Collins & May Mining Company Inc → No 1; 1990-01-01 to 1993-04-13; source msha-controller-operator-history
- **controller_controls_operator:** Collins Roger B → Collins & May Mining Company Inc; 1990-01-01 to 1993-04-13; source msha-controller-operator-history
- **operator_operates_mine:** Diamond T Coal Corp → No 1; 1993-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tackett Vernon W → No 1; 1993-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tackett Vernon W → Diamond T Coal Corp; 1993-04-14 to current/open; source msha-controller-operator-history