# Relationship history for MSHA mine 3400460

Current hierarchy: **Martin Marietta Materials Inc → Meridian Aggregates Company, A Limited Partnership → Broken Bow 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:** Ives  Moyer → Broken Bow Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Anderson-Dunham Inc → Broken Bow Sand & Gravel; 1950-01-01 to 1990-01-28; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Dunham  et al → Broken Bow Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Dunham  et al → Anderson-Dunham Inc; 1950-01-01 to 1990-01-28; source msha-controller-operator-history
- **operator_operates_mine:** B & B Sand & Gravel → Broken Bow Sand & Gravel; 1990-01-29 to 2003-03-12; source msha-controller-operator-history
- **controller_controls_operator:** Ives  Moyer → B & B Sand & Gravel; 1990-01-29 to 2003-03-12; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Broken Bow Sand & Gravel; 2001-04-03 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Broken Bow Sand & Gravel Inc → Broken Bow Sand & Gravel; 2003-03-13 to 2007-03-27; source msha-controller-operator-history
- **controller_controls_mine:** Ives  Moyer → Broken Bow Sand & Gravel; 2003-03-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ives  Moyer → Broken Bow Sand & Gravel Inc; 2003-03-13 to 2007-03-27; source msha-controller-operator-history
- **operator_operates_mine:** Meridian Aggregates Company, A Limited Partnership → Broken Bow Sand & Gravel; 2007-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Meridian Aggregates Company, A Limited Partnership; 2007-03-28 to current/open; source msha-controller-operator-history