# Relationship history for MSHA mine 0402272

Current hierarchy: **Cimenteries Cbr Cementbedrijven → Calaveras Cement Company → San Andreas Cement Plant**

- 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

- **operator_operates_mine:** Flintkote Cement Company → San Andreas Cement Plant; 1950-01-01 to 1980-04-06; source msha-controller-operator-history
- **controller_controls_mine:** Flintkote Company → San Andreas Cement Plant; 1950-01-01 to 1980-04-06; source msha-controller-operator-history
- **controller_controls_operator:** Flintkote Company → Flintkote Cement Company; 1950-01-01 to 1980-04-06; source msha-controller-operator-history
- **operator_operates_mine:** Calaveras Cement Company → San Andreas Cement Plant; 1980-04-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cimenteries Cbr Cementbedrijven → San Andreas Cement Plant; 1980-04-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cimenteries Cbr Cementbedrijven → Calaveras Cement Company; 1980-04-07 to current/open; source msha-controller-operator-history