# Relationship history for MSHA mine 0201992

Current hierarchy: **Hansen Wilbur → Gold Standard Mines Inc → Tyro**

- 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:** Gold Standard Mines Inc → Tyro; 1980-06-01 to 1980-10-26; source msha-controller-operator-history
- **controller_controls_mine:** Hansen Wilbur → Tyro; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hansen Wilbur → Gold Standard Mines Inc; 1980-06-01 to 1980-10-26; source msha-controller-operator-history
- **operator_operates_mine:** Equitable Corp Of Nevada → Tyro; 1980-10-27 to 1981-03-23; source msha-controller-operator-history
- **controller_controls_mine:** Hughes Robert W → Tyro; 1980-10-27 to 1981-03-23; source msha-controller-operator-history
- **controller_controls_operator:** Hughes Robert W → Equitable Corp Of Nevada; 1980-10-27 to 1981-03-23; source msha-controller-operator-history
- **operator_operates_mine:** Gold Standard Mines Inc → Tyro; 1981-03-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hansen Wilbur → Gold Standard Mines Inc; 1981-03-24 to current/open; source msha-controller-operator-history