# Relationship history for MSHA mine 4101256

Current hierarchy: **Joe R  Williams Jr → Bilbrough Marble Division → Bilbrough Marble Division**

- 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

- **operator_operates_mine:** Bilbrough Marble Company → Bilbrough Marble Division; 1950-01-01 to 1980-06-25; source msha-controller-operator-history
- **controller_controls_mine:** Jim Walter Corp → Bilbrough Marble Division; 1950-01-01 to 1980-06-25; source msha-controller-operator-history
- **controller_controls_operator:** Jim Walter Corp → Bilbrough Marble Company; 1950-01-01 to 1980-06-25; source msha-controller-operator-history
- **controller_controls_mine:** Joe R  Williams Jr → Bilbrough Marble Division; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Texas Architectural Aggregate Inc → Bilbrough Marble Division; 1980-06-26 to 2003-01-14; source msha-controller-operator-history
- **controller_controls_operator:** Joe R  Williams Jr → Texas Architectural Aggregate Inc; 1980-06-26 to 2003-01-14; source msha-controller-operator-history
- **controller_controls_mine:** Joe R  Williams Jr → Bilbrough Marble Division; 1992-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bilbrough Marble Division → Bilbrough Marble Division; 2003-01-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joe R  Williams Jr → Bilbrough Marble Division; 2003-01-15 to current/open; source msha-controller-operator-history