# Relationship history for MSHA mine 2102979

Current hierarchy: **GCC SAB de CV → Consolidated Ready Mix → PORTABLE CRUSHER**

- 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:** Thomas  Henrich → PORTABLE CRUSHER; 1984-07-20 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Henrich & Sons Inc → PORTABLE CRUSHER; 1988-08-01 to 2006-01-17; source msha-controller-operator-history
- **controller_controls_operator:** Thomas  Henrich → Henrich & Sons Inc; 1988-08-01 to 2006-01-17; source msha-controller-operator-history
- **operator_operates_mine:** Consolidated Ready Mix → PORTABLE CRUSHER; 2006-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** GCC SAB de CV → PORTABLE CRUSHER; 2006-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** GCC SAB de CV → Consolidated Ready Mix; 2006-01-18 to current/open; source msha-controller-operator-history