# Relationship history for MSHA mine 4103848

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Southwest LLC → Martin Marietta Merkel 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Ralph E  Janes III → Martin Marietta Merkel Plant; 1950-01-01 to 2013-12-31; source msha-controller-operator-history
- **operator_operates_mine:** R .E. Janes Gravel Company → Martin Marietta Merkel Plant; 1994-11-01 to 2024-12-12; source msha-controller-operator-history
- **controller_controls_operator:** Ralph E  Janes III → R .E. Janes Gravel Company; 1994-11-01 to 2013-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Martin Marietta Merkel Plant; 2007-11-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ralph E  Janes IV et al → Martin Marietta Merkel Plant; 2014-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ralph E  Janes IV et al → R .E. Janes Gravel Company; 2014-01-01 to 2024-12-12; source msha-controller-operator-history
- **controller_controls_operator:** Brian T  Etchison et al → R .E. Janes Gravel Company; 2014-01-01 to 2024-12-12; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Southwest LLC → Martin Marietta Merkel Plant; 2024-12-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Southwest LLC; 2024-12-13 to current/open; source msha-controller-operator-history