# Relationship history for MSHA mine 3500972

Current hierarchy: **Lance D  Hamlin → Hamlin & Son Construction → HAMLIN & SON CRUSHING**

- 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:** U S Bureau Of Land Management → HAMLIN & SON CRUSHING; 1950-01-01 to 1999-06-28; source msha-controller-operator-history
- **controller_controls_mine:** United States Government → HAMLIN & SON CRUSHING; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Government → U S Bureau Of Land Management; 1950-01-01 to 1999-06-28; source msha-controller-operator-history
- **operator_operates_mine:** Hamlin & Son Construction → HAMLIN & SON CRUSHING; 1999-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lance D  Hamlin → HAMLIN & SON CRUSHING; 1999-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lance D  Hamlin → Hamlin & Son Construction; 1999-06-29 to current/open; source msha-controller-operator-history