# Relationship history for MSHA mine 4104897

Current hierarchy: **Daniel Marcus  Frost → Frost Crushed Stone Inc → Frost Crushed Stone #4 Simmons Pit**

- 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:** Daniel Marcus  Frost → Frost Crushed Stone #4 Simmons Pit; 1992-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Frost Crushed Stone Inc → Frost Crushed Stone #4 Simmons Pit; 2011-07-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniel Marcus  Frost → Frost Crushed Stone Inc; 2011-07-25 to current/open; source msha-controller-operator-history