# Relationship history for MSHA mine 1101302

Current hierarchy: **Bush A K → Bush Gravel → BUSH GRAVEL**

- 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:** H M Nash Company → BUSH GRAVEL; 1950-01-01 to 1988-12-06; source msha-controller-operator-history
- **controller_controls_mine:** Nash H M → BUSH GRAVEL; 1950-01-01 to 1988-12-06; source msha-controller-operator-history
- **controller_controls_operator:** Nash H M → H M Nash Company; 1950-01-01 to 1988-12-06; source msha-controller-operator-history
- **operator_operates_mine:** Bush Gravel → BUSH GRAVEL; 1988-12-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bush A K → BUSH GRAVEL; 1988-12-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bush A K → Bush Gravel; 1988-12-07 to current/open; source msha-controller-operator-history