# Relationship history for MSHA mine 1900956

Current hierarchy: **John M Matteson; Steven E Goodman → Worcester Sand & Stone → Worcester Sand & Stone**

- 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:** Worcester Sand & Gravel Company Inc → Worcester Sand & Stone; 1950-01-01 to 2020-01-26; source msha-controller-operator-history
- **controller_controls_mine:** Anthony J Trotto et al → Worcester Sand & Stone; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anthony J Trotto et al → Worcester Sand & Gravel Company Inc; 1950-01-01 to 2020-01-26; source msha-controller-operator-history
- **operator_operates_mine:** Worcester Sand & Stone → Worcester Sand & Stone; 2020-01-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Steven E Goodman et al → Worcester Sand & Stone; 2020-01-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steven E Goodman et al → Worcester Sand & Stone; 2020-01-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John M Matteson et al → Worcester Sand & Stone; 2020-01-27 to current/open; source msha-controller-operator-history