# Relationship history for MSHA mine 3600055

Current hierarchy: **New Enterprise Stone & Lime Company Inc; New Enterprise Stone & Lime Com → Eastern Industries Inc → Derry Township Quarry**

- 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

- **controller_controls_mine:** M Lee  Eberhart Jr → Derry Township Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stabler Companies Inc → Derry Township Quarry; 1950-01-01 to 2008-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Derry Limestone Company Inc → Derry Township Quarry; 1950-01-01 to 1979-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Quigley Robert P → Derry Township Quarry; 1950-01-01 to 1979-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Quigley Robert P → Derry Limestone Company Inc; 1950-01-01 to 1979-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Faylor-Middlecreek Inc → Derry Township Quarry; 1979-08-01 to 1990-03-08; source msha-controller-operator-history
- **controller_controls_operator:** M Lee  Eberhart Jr → Faylor-Middlecreek Inc; 1979-08-01 to 1990-03-08; source msha-controller-operator-history
- **operator_operates_mine:** Eastern Industries Inc → Derry Township Quarry; 1990-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stabler Companies Inc → Eastern Industries Inc; 1990-03-09 to 2008-01-31; source msha-controller-operator-history
- **controller_controls_mine:** New Enterprise Stone & Lime Company Inc → Derry Township Quarry; 2008-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** New Enterprise Stone & Lime Company Inc → Eastern Industries Inc; 2008-02-01 to current/open; source msha-controller-operator-history