# Relationship history for MSHA mine 0201900

Current hierarchy: **Linda  Edstrom → Edstrom Construction → Ehrenberg**

- 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:** Lawrence E  Ashton et al → Ehrenberg; 1950-01-01 to 2017-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Ashton Company Inc → Ehrenberg; 1979-01-01 to 1980-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Lawrence E  Ashton et al → Ashton Company Inc; 1979-01-01 to 1980-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Cindy L  Ashton et al → Ashton Company Inc; 1979-01-01 to 1980-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Harold W  Ashton et al → Ashton Company Inc; 1979-01-01 to 1980-08-17; source msha-controller-operator-history
- **operator_operates_mine:** U S Bureau Of Reclamation → Ehrenberg; 1980-08-18 to 1986-09-07; source msha-controller-operator-history
- **controller_controls_mine:** United States Government → Ehrenberg; 1980-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Government → U S Bureau Of Reclamation; 1980-08-18 to 1986-09-07; source msha-controller-operator-history
- **operator_operates_mine:** Rip-Rap Inc → Ehrenberg; 1986-09-08 to 1988-10-24; source msha-controller-operator-history
- **controller_controls_mine:** Siler Grant L → Ehrenberg; 1986-09-08 to 1988-10-24; source msha-controller-operator-history
- **controller_controls_operator:** Siler Grant L → Rip-Rap Inc; 1986-09-08 to 1988-10-24; source msha-controller-operator-history
- **operator_operates_mine:** Hodge Construction Company → Ehrenberg; 1988-10-25 to 1992-02-10; source msha-controller-operator-history
- **controller_controls_mine:** Hodge Edith → Ehrenberg; 1988-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hodge Edith → Hodge Construction Company; 1988-10-25 to 1992-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Edstrom Construction → Ehrenberg; 1992-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Linda  Edstrom → Ehrenberg; 1992-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Linda  Edstrom → Edstrom Construction; 1992-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nena  Ashton et al → Ehrenberg; 2017-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nena  Ashton et al → Ashton Company Inc; 2017-12-01 to 1980-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Larry E  Ashton et al → Ashton Company Inc; 2017-12-01 to 1980-08-17; source msha-controller-operator-history