# Relationship history for MSHA mine 4104379

Current hierarchy: **Ritchie A  Byley → H.G. Byley & Sons Const Inc. → H. G. Byley & Sons Const. INc.**

- 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:** Ritchie A  Byley  et al → H. G. Byley & Sons Const. INc.; 1992-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** H.G. Byley & Sons Const Inc. → H. G. Byley & Sons Const. INc.; 2002-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ritchie A  Byley  et al → H.G. Byley & Sons Const Inc.; 2002-07-10 to current/open; source msha-controller-operator-history