# Relationship history for MSHA mine 0202718

Current hierarchy: **Richard (Dick)  Merritt → Dick Merritt Construction → Sacremento Mine**

- 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:** Richard (Dick)  Merritt → Sacremento Mine; 1988-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dick Merritt Construction → Sacremento Mine; 1997-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard (Dick)  Merritt → Dick Merritt Construction; 1997-10-01 to current/open; source msha-controller-operator-history