# Relationship history for MSHA mine 1300729

Current hierarchy: **T M  Flynn; T L  Flynn → Aggregate Materials Company → River Dredging**

- 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:** Dubuque Sand & Gravel Company → River Dredging; 1950-01-01 to 1985-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Thompson Floyd → River Dredging; 1950-01-01 to 1985-08-04; source msha-controller-operator-history
- **controller_controls_operator:** Thompson Floyd → Dubuque Sand & Gravel Company; 1950-01-01 to 1985-08-04; source msha-controller-operator-history
- **operator_operates_mine:** Aggregate Materials Company → River Dredging; 1985-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** T L  Flynn  et al → River Dredging; 1985-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** T L  Flynn  et al → Aggregate Materials Company; 1985-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** T M  Flynn  et al → Aggregate Materials Company; 1985-08-05 to current/open; source msha-controller-operator-history