# Relationship history for MSHA mine 3400681

Current hierarchy: **Richmond H  Hill III → Oklahoma Aztec Company Inc → Asher #1**

- 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:** Corff Sand & Gravel Company → Asher #1; 1950-01-01 to 1988-04-11; source msha-controller-operator-history
- **controller_controls_mine:** N C  Corff → Asher #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** N C  Corff → Corff Sand & Gravel Company; 1950-01-01 to 1988-04-11; source msha-controller-operator-history
- **operator_operates_mine:** Corff Sand & Gravel Inc → Asher #1; 1988-04-12 to 1992-05-05; source msha-controller-operator-history
- **controller_controls_mine:** James A  Corff → Asher #1; 1988-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James A  Corff → Corff Sand & Gravel Inc; 1988-04-12 to 1992-05-05; source msha-controller-operator-history
- **operator_operates_mine:** Oklahoma Aztec Company Inc → Asher #1; 1992-05-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richmond H  Hill III → Asher #1; 1992-05-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richmond H  Hill III → Oklahoma Aztec Company Inc; 1992-05-06 to current/open; source msha-controller-operator-history