# Relationship history for MSHA mine 1201504

Current hierarchy: **Nathaniel  Huffman → Berry Materials Corp → Jefferson Plant No 3 Quarry & 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

- **operator_operates_mine:** Berry Materials Corp → Jefferson Plant No 3 Quarry & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nathaniel  Huffman  et al → Jefferson Plant No 3 Quarry & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nathaniel  Huffman  et al → Berry Materials Corp; 1950-01-01 to current/open; source msha-controller-operator-history