# Relationship history for MSHA mine 2200381

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc. → R&S Sand & Gravel**

- 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

- **controller_controls_mine:** Martin Marietta Materials Inc → R&S Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Alton Clay  Rakestraw → R&S Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** M & B Construction Inc → R&S Sand & Gravel; 1950-01-01 to 1980-02-10; source msha-controller-operator-history
- **controller_controls_mine:** G B  Beasley → R&S Sand & Gravel; 1950-01-01 to 1980-02-10; source msha-controller-operator-history
- **controller_controls_operator:** G B  Beasley → M & B Construction Inc; 1950-01-01 to 1980-02-10; source msha-controller-operator-history
- **operator_operates_mine:** R & S Haulers & Distributors Inc → R&S Sand & Gravel; 1980-02-11 to 1997-10-07; source msha-controller-operator-history
- **controller_controls_operator:** Alton Clay  Rakestraw → R & S Haulers & Distributors Inc; 1980-02-11 to 1997-10-07; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → R&S Sand & Gravel; 1997-10-08 to 2005-07-17; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1997-10-08 to 2005-07-17; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → R&S Sand & Gravel; 2005-07-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2005-07-18 to current/open; source msha-controller-operator-history