# Relationship history for MSHA mine 4202534

Current hierarchy: **CRH PLC → Staker & Parson Companies → Crusher #6**

- 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:** Wayne L  Nielson et al → Crusher #6; 1982-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Crusher #6; 2002-05-30 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Nielson Construction → Crusher #6; 2009-09-10 to 2016-02-10; source msha-controller-operator-history
- **controller_controls_operator:** Wayne L  Nielson et al → Nielson Construction; 2009-09-10 to 2016-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Staker & Parson Companies → Crusher #6; 2016-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Staker & Parson Companies; 2016-02-11 to current/open; source msha-controller-operator-history