# Relationship history for MSHA mine 3604804

Current hierarchy: **Calypso Energy Holdings LLC → Northampton Fuel Supply Company, Inc. → #6 Bank**

- 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

- **controller_controls_mine:** Vincent  Kassa → #6 Bank; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Silverbrook Anthracite Inc → #6 Bank; 1973-01-01 to 2018-06-19; source msha-controller-operator-history
- **controller_controls_operator:** Vincent  Kassa → Silverbrook Anthracite Inc; 1973-01-01 to 2018-06-19; source msha-controller-operator-history
- **controller_controls_mine:** Calypso Energy Holdings LLC → #6 Bank; 2011-04-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Northampton Fuel Supply Company, Inc. → #6 Bank; 2018-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Calypso Energy Holdings LLC → Northampton Fuel Supply Company, Inc.; 2018-06-20 to current/open; source msha-controller-operator-history