# Relationship history for MSHA mine 1202159

Current hierarchy: **John E  Merritt → Merritt Sand & Gravel Inc → MERRITT SAND & GRAVEL INC.**

- 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:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → MERRITT SAND & GRAVEL INC.; 1950-01-01 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** John E  Merritt → MERRITT SAND & GRAVEL INC.; 1992-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Vulcan Materials Company → MERRITT SAND & GRAVEL INC.; 1994-05-01 to 1995-02-16; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Materials Company; 1994-05-01 to 1995-02-16; source msha-controller-operator-history
- **operator_operates_mine:** Merritt Sand & Gravel Inc → MERRITT SAND & GRAVEL INC.; 1995-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John E  Merritt → Merritt Sand & Gravel Inc; 1995-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → MERRITT SAND & GRAVEL INC.; 2007-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Vulcan Materials Company; 2007-11-16 to 1995-02-16; source msha-controller-operator-history