# Relationship history for MSHA mine 3300355

Current hierarchy: **Mack S  Moon → Guernsey Limestone Company Inc → Guernsey Limestone Company Incorporated**

- 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:** Harley E Calvin & Company → Guernsey Limestone Company Incorporated; 1950-01-01 to 1985-06-12; source msha-controller-operator-history
- **controller_controls_mine:** Calvin Harley E Et Al → Guernsey Limestone Company Incorporated; 1950-01-01 to 1985-06-12; source msha-controller-operator-history
- **controller_controls_operator:** Calvin Harley E Et Al → Harley E Calvin & Company; 1950-01-01 to 1985-06-12; source msha-controller-operator-history
- **operator_operates_mine:** Guernsey Limestone Company Inc → Guernsey Limestone Company Incorporated; 1985-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mack S  Moon → Guernsey Limestone Company Incorporated; 1985-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mack S  Moon → Guernsey Limestone Company Inc; 1985-06-13 to current/open; source msha-controller-operator-history