# Relationship history for MSHA mine 0503135

Current hierarchy: **Skanska AB → Nielsons Skanska Inc → El Jay Double Cone #1**

- 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:** Nielsons Inc → El Jay Double Cone #1; 1950-01-01 to 1980-03-24; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc → El Jay Double Cone #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Nielsons Inc; 1950-01-01 to 1980-03-24; source msha-controller-operator-history
- **controller_controls_mine:** Nielsons Holding Company → El Jay Double Cone #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Nielsons Inc → El Jay Double Cone #1; 1980-03-25 to 1995-09-04; source msha-controller-operator-history
- **controller_controls_operator:** Nielsons Holding Company → Nielsons Inc; 1980-03-25 to 1995-09-04; source msha-controller-operator-history
- **operator_operates_mine:** Nielsons Inc → El Jay Double Cone #1; 1995-09-05 to 1998-04-07; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → El Jay Double Cone #1; 1995-09-05 to 1998-04-07; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Nielsons Inc; 1995-09-05 to 1998-04-07; source msha-controller-operator-history
- **operator_operates_mine:** Nielsons Inc → El Jay Double Cone #1; 1998-04-08 to 2006-04-24; source msha-controller-operator-history
- **controller_controls_mine:** Skanska AB → El Jay Double Cone #1; 1998-04-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Skanska AB → Nielsons Inc; 1998-04-08 to 2006-04-24; source msha-controller-operator-history
- **controller_controls_mine:** Skanska AB → El Jay Double Cone #1; 2001-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Nielsons Skanska Inc → El Jay Double Cone #1; 2006-04-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Skanska AB → Nielsons Skanska Inc; 2006-04-25 to current/open; source msha-controller-operator-history