# Relationship history for MSHA mine 3901285

Current hierarchy: **Forsyth James R-Richard L Mathieson → Custer Gravel By-Products Inc → Custer Gravel By-Products Incorporated**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Ventling Mining Inc → Custer Gravel By-Products Incorporated; 1982-09-01 to 1985-05-23; source msha-controller-operator-history
- **controller_controls_mine:** Ventling Lawrence M → Custer Gravel By-Products Incorporated; 1982-09-01 to 1985-05-23; source msha-controller-operator-history
- **controller_controls_operator:** Ventling Lawrence M → Ventling Mining Inc; 1982-09-01 to 1985-05-23; source msha-controller-operator-history
- **operator_operates_mine:** Custer Gravel By-Products Inc → Custer Gravel By-Products Incorporated; 1985-05-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Forsyth James R-Richard L Mathieson Et Al → Custer Gravel By-Products Incorporated; 1985-05-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Forsyth James R-Richard L Mathieson Et Al → Custer Gravel By-Products Inc; 1985-05-24 to current/open; source msha-controller-operator-history