# Relationship history for MSHA mine 1400681

Current hierarchy: **J R  Isch → MK MINERALS → MK MINERALS**

- 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

- **operator_operates_mine:** Martin Marietta Aggregates → MK MINERALS; 1950-01-01 to 1981-04-19; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → MK MINERALS; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1950-01-01 to 1981-04-19; source msha-controller-operator-history
- **controller_controls_mine:** Herzog Contracting Corp → MK MINERALS; 1980-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Herzog Contracting Corp → MK MINERALS; 1981-04-20 to 2000-06-01; source msha-controller-operator-history
- **controller_controls_operator:** Herzog Contracting Corp → Herzog Contracting Corp; 1981-04-20 to 2000-06-01; source msha-controller-operator-history
- **operator_operates_mine:** MK MINERALS → MK MINERALS; 2000-06-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry E  Moore → MK MINERALS; 2000-06-02 to 2003-01-02; source msha-controller-operator-history
- **controller_controls_operator:** Larry E  Moore → MK MINERALS; 2000-06-02 to 2003-01-02; source msha-controller-operator-history
- **controller_controls_mine:** J R  Isch et al → MK MINERALS; 2003-01-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** J R  Isch et al → MK MINERALS; 2003-01-03 to current/open; source msha-controller-operator-history