# Relationship history for MSHA mine 3609933

Current hierarchy: **Anthony  Pykus; William B  Pykus → Bill Pykus Excavating Inc. → Springer Quarry**

- 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

- **operator_operates_mine:** Bill Pykus Excavating Inc. → Springer Quarry; 2011-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** William L  Pykus → Springer Quarry; 2011-06-16 to 2023-05-25; source msha-controller-operator-history
- **controller_controls_operator:** William L  Pykus → Bill Pykus Excavating Inc.; 2011-06-16 to 2023-05-25; source msha-controller-operator-history
- **controller_controls_mine:** Anthony  Pykus et al → Springer Quarry; 2023-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anthony  Pykus et al → Bill Pykus Excavating Inc.; 2023-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William B  Pykus et al → Bill Pykus Excavating Inc.; 2023-05-26 to current/open; source msha-controller-operator-history