# Relationship history for MSHA mine 3301993

Current hierarchy: **SCIH Salt Holdings, Inc → Morton Salt Inc → Morton Salt Fairport Mine**

- 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:** Morton Salt Division → Morton Salt Fairport Mine; 1950-01-01 to 1999-06-20; source msha-controller-operator-history
- **controller_controls_mine:** Morton International Inc → Morton Salt Fairport Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Morton International Inc → Morton Salt Division; 1950-01-01 to 1999-06-20; source msha-controller-operator-history
- **operator_operates_mine:** Morton Salt Div/Morton International Inc → Morton Salt Fairport Mine; 1999-06-21 to 2010-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Rohm & Haas Company → Morton Salt Fairport Mine; 1999-06-21 to 2009-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Rohm & Haas Company → Morton Salt Div/Morton International Inc; 1999-06-21 to 2009-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Dow Chemical Company → Morton Salt Fairport Mine; 2009-04-01 to 2009-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Dow Chemical Company → Morton Salt Div/Morton International Inc; 2009-04-01 to 2009-09-30; source msha-controller-operator-history
- **controller_controls_mine:** K+S Aktiengesellschaft → Morton Salt Fairport Mine; 2009-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** K+S Aktiengesellschaft → Morton Salt Div/Morton International Inc; 2009-10-01 to 2010-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Morton Salt Inc → Morton Salt Fairport Mine; 2010-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** K+S Aktiengesellschaft → Morton Salt Fairport Mine; 2010-10-01 to 2021-04-29; source msha-controller-operator-history
- **controller_controls_operator:** K+S Aktiengesellschaft → Morton Salt Inc; 2010-10-01 to 2021-04-29; source msha-controller-operator-history
- **controller_controls_mine:** SCIH Salt Holdings, Inc → Morton Salt Fairport Mine; 2021-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** SCIH Salt Holdings, Inc → Morton Salt Inc; 2021-04-30 to current/open; source msha-controller-operator-history