# Relationship history for MSHA mine 0504775

Current hierarchy: **Big Bridge Big Dog PTY LTD → ICG ADDCAR Systems LLC → Isaacs Run HWM**

- 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:** Horizon Natural Resources Incorporated → Isaacs Run HWM; 1992-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mining Technologies Inc. → Isaacs Run HWM; 2003-11-28 to 2004-10-26; source msha-controller-operator-history
- **controller_controls_operator:** Horizon Natural Resources Incorporated → Mining Technologies Inc.; 2003-11-28 to 2004-10-26; source msha-controller-operator-history
- **operator_operates_mine:** ICG ADDCAR Systems LLC → Isaacs Run HWM; 2004-10-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** International Coal Group Inc (ICG) → Isaacs Run HWM; 2004-10-27 to 2011-06-14; source msha-controller-operator-history
- **controller_controls_operator:** International Coal Group Inc (ICG) → ICG ADDCAR Systems LLC; 2004-10-27 to 2011-06-14; source msha-controller-operator-history
- **controller_controls_mine:** Arch Resources Inc → Isaacs Run HWM; 2011-06-15 to 2014-02-11; source msha-controller-operator-history
- **controller_controls_operator:** Arch Resources Inc → ICG ADDCAR Systems LLC; 2011-06-15 to 2014-02-11; source msha-controller-operator-history
- **controller_controls_mine:** ADDCAR Holdings Pty.Ltd. → Isaacs Run HWM; 2014-02-12 to 2020-08-13; source msha-controller-operator-history
- **controller_controls_operator:** ADDCAR Holdings Pty.Ltd. → ICG ADDCAR Systems LLC; 2014-02-12 to 2020-08-13; source msha-controller-operator-history
- **controller_controls_mine:** Big Bridge Big Dog PTY LTD → Isaacs Run HWM; 2020-08-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Big Bridge Big Dog PTY LTD → ICG ADDCAR Systems LLC; 2020-08-14 to current/open; source msha-controller-operator-history