# Relationship history for MSHA mine 1102027

Current hierarchy: **Amrize Ltd → Meyer Material Company → Mc Graw Pit #14**

- 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:** Meyer Material Company → Mc Graw Pit #14; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Meyer Material Acquisition Corp Et Al → Mc Graw Pit #14; 1950-01-01 to 2011-07-11; source msha-controller-operator-history
- **controller_controls_operator:** Meyer Material Acquisition Corp Et Al → Meyer Material Company; 1950-01-01 to 2011-07-11; source msha-controller-operator-history
- **controller_controls_mine:** Aggregate Industries PLC → Mc Graw Pit #14; 2011-07-12 to 2015-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Aggregate Industries PLC → Meyer Material Company; 2011-07-12 to 2015-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Holcim Ltd → Mc Graw Pit #14; 2015-07-10 to 2025-06-22; source msha-controller-operator-history
- **controller_controls_operator:** Holcim Ltd → Meyer Material Company; 2015-07-10 to 2025-06-22; source msha-controller-operator-history
- **controller_controls_mine:** Amrize Ltd → Mc Graw Pit #14; 2025-06-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Amrize Ltd → Meyer Material Company; 2025-06-23 to current/open; source msha-controller-operator-history