# Relationship history for MSHA mine 2301922

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc. → Plant #65**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Martin Marietta Materials Inc → Plant #65; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → Plant #65; 1985-07-01 to 2003-09-14; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1985-07-01 to 2003-09-14; source msha-controller-operator-history
- **controller_controls_mine:** Brady D  Meldrem → Plant #65; 1997-01-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Con-Agg Llc → Plant #65; 2001-12-28 to 2010-09-14; source msha-controller-operator-history
- **operator_operates_mine:** Norris Asphalt Paving Company → Plant #65; 2003-09-15 to 2012-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Brady D  Meldrem → Norris Asphalt Paving Company; 2003-09-15 to 2012-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Plant #65; 2010-09-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Norris Quarries, LLC → Plant #65; 2012-02-29 to 2016-05-19; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Plant #65; 2012-02-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Norris Quarries, LLC; 2012-02-29 to 2016-05-19; source msha-controller-operator-history
- **operator_operates_mine:** Con-Agg Companies, LLC → Plant #65; 2016-05-20 to 2026-03-23; source msha-controller-operator-history
- **controller_controls_operator:** Con-Agg Llc → Con-Agg Companies, LLC; 2016-05-20 to 2010-09-14; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Con-Agg Companies, LLC; 2016-05-20 to 2026-03-23; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → Plant #65; 2026-03-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2026-03-24 to current/open; source msha-controller-operator-history