# Relationship history for MSHA mine 4103914

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Of Tx, Inc. → Decatur Sand 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

- **controller_controls_mine:** Connie  Spradley → Decatur Sand Plant; 1990-01-31 to 1999-09-03; source msha-controller-operator-history
- **operator_operates_mine:** Marock Inc → Decatur Sand Plant; 1996-05-01 to 1999-09-03; source msha-controller-operator-history
- **controller_controls_operator:** Connie  Spradley → Marock Inc; 1996-05-01 to 1999-09-03; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Of Tx, Inc. → Decatur Sand Plant; 1999-09-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Decatur Sand Plant; 1999-09-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Of Tx, Inc.; 1999-09-04 to current/open; source msha-controller-operator-history