# Relationship history for MSHA mine 4503540

Current hierarchy: **Michael T  Crawford; Jerome W  Fisher → Skagit Aggregates, LLC → Rockport 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** 3DH Aggregates → Rockport Pit; 2003-05-13 to 2017-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Dave M  Harvin → Rockport Pit; 2003-05-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dave M  Harvin → 3DH Aggregates; 2003-05-13 to 2017-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Jerome W  Fisher et al → Rockport Pit; 2012-04-30 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Skagit Aggregates, LLC → Rockport Pit; 2017-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jerome W  Fisher et al → Skagit Aggregates, LLC; 2017-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael T  Crawford et al → Skagit Aggregates, LLC; 2017-05-01 to current/open; source msha-controller-operator-history