# Relationship history for MSHA mine 0300388

Current hierarchy: **Charles B  Germer → Dredging Inc → Big Sandy Iii**

- 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:** Criss & Shaver Inc → Big Sandy Iii; 1950-01-01 to 1981-09-21; source msha-controller-operator-history
- **controller_controls_mine:** Shaver W H → Big Sandy Iii; 1950-01-01 to 1981-09-21; source msha-controller-operator-history
- **controller_controls_operator:** Shaver W H → Criss & Shaver Inc; 1950-01-01 to 1981-09-21; source msha-controller-operator-history
- **operator_operates_mine:** Dredging Inc → Big Sandy Iii; 1981-09-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Charles B  Germer → Big Sandy Iii; 1981-09-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles B  Germer → Dredging Inc; 1981-09-22 to current/open; source msha-controller-operator-history