# Relationship history for MSHA mine 2601608

Current hierarchy: **Sundance Gold Ltd → Rule Resources Usa Inc → Big Comstock 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

- **operator_operates_mine:** Big Comstock Mine Corp → Big Comstock Mine; 1980-02-01 to 1983-10-24; source msha-controller-operator-history
- **controller_controls_mine:** Tankersley W B → Big Comstock Mine; 1980-02-01 to 1983-10-24; source msha-controller-operator-history
- **controller_controls_operator:** Tankersley W B → Big Comstock Mine Corp; 1980-02-01 to 1983-10-24; source msha-controller-operator-history
- **operator_operates_mine:** Rule Resources Usa Inc → Big Comstock Mine; 1983-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sundance Gold Ltd → Big Comstock Mine; 1983-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sundance Gold Ltd → Rule Resources Usa Inc; 1983-10-25 to current/open; source msha-controller-operator-history