# Relationship history for MSHA mine 2601663

Current hierarchy: **Garcia Robert-Willis R Dees → Bullfrog Enterprises → Montgomery-Shoshone**

- 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:** Milling Company → Montgomery-Shoshone; 1980-07-01 to 1982-08-23; source msha-controller-operator-history
- **controller_controls_mine:** W M  Kerr et al → Montgomery-Shoshone; 1980-07-01 to 1982-08-23; source msha-controller-operator-history
- **controller_controls_operator:** W M  Kerr et al → Milling Company; 1980-07-01 to 1982-08-23; source msha-controller-operator-history
- **operator_operates_mine:** Bullfrog Enterprises → Montgomery-Shoshone; 1982-08-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Garcia Robert-Willis R Dees Et Al → Montgomery-Shoshone; 1982-08-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Garcia Robert-Willis R Dees Et Al → Bullfrog Enterprises; 1982-08-24 to current/open; source msha-controller-operator-history