# Relationship history for MSHA mine 2101274

Current hierarchy: **McCormick Inc → Northern Improvement Company → Felton Pit & Mill**

- 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

- **controller_controls_mine:** McCormick Inc → Felton Pit & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ames Sand & Gravel Inc → Felton Pit & Mill; 1950-01-01 to 1993-04-19; source msha-controller-operator-history
- **controller_controls_mine:** Donald J  Ames → Felton Pit & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donald J  Ames → Ames Sand & Gravel Inc; 1950-01-01 to 1993-04-19; source msha-controller-operator-history
- **operator_operates_mine:** Ames Sand & Gravel → Felton Pit & Mill; 1993-04-20 to 2008-04-30; source msha-controller-operator-history
- **controller_controls_mine:** McCormick Inc → Felton Pit & Mill; 1993-04-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** McCormick Inc → Ames Sand & Gravel; 1993-04-20 to 2008-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Northern Improvement Company → Felton Pit & Mill; 2008-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** McCormick Inc → Northern Improvement Company; 2008-05-01 to current/open; source msha-controller-operator-history