# Relationship history for MSHA mine 0405120

Current hierarchy: **Richard B  Harmon → Standard Industrial Minerals Inc → PACIFIC 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 B  Harmon et al → PACIFIC MINE; 1987-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Standard Industrial Minerals Inc → PACIFIC MINE; 1990-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard B  Harmon et al → Standard Industrial Minerals Inc; 1990-11-01 to current/open; source msha-controller-operator-history