# Relationship history for MSHA mine 3001255

Current hierarchy: **Todd K  Campbell → Togemco → Hulberton**

- 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:** Gene Dewitt Corporation → Hulberton; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Medina Sandstone Quarry Inc → Hulberton; 1950-01-01 to 1992-03-15; source msha-controller-operator-history
- **controller_controls_mine:** Greater Buffalo Press → Hulberton; 1950-01-01 to 1992-03-15; source msha-controller-operator-history
- **controller_controls_operator:** Greater Buffalo Press → Medina Sandstone Quarry Inc; 1950-01-01 to 1992-03-15; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Hulberton; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Genesee Le Roy Stone Corp → Hulberton; 1992-03-16 to 2001-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Gene Dewitt Corporation → Genesee Le Roy Stone Corp; 1992-03-16 to 2001-10-11; source msha-controller-operator-history
- **operator_operates_mine:** Togemco, Inc. → Hulberton; 2001-10-12 to 2003-11-23; source msha-controller-operator-history
- **controller_controls_mine:** Todd K  Campbell → Hulberton; 2001-10-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Todd K  Campbell → Togemco, Inc.; 2001-10-12 to 2003-11-23; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates New York Inc. → Hulberton; 2003-11-24 to 2005-05-10; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates New York Inc.; 2003-11-24 to 2005-05-10; source msha-controller-operator-history
- **operator_operates_mine:** Togemco → Hulberton; 2005-05-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Todd K  Campbell → Togemco; 2005-05-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Hulberton; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates New York Inc.; 2007-08-23 to 2005-05-10; source msha-controller-operator-history