# Relationship history for MSHA mine 3401903

Current hierarchy: **Michael Chad  Robinson; Mason  Warren → TerraCore Materials, LLC → HILLTOP 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:** Bluebird Stone → HILLTOP MINE; 2002-10-28 to 2008-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Tommy  Caldwell  et al → HILLTOP MINE; 2002-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tommy  Caldwell  et al → Bluebird Stone; 2002-10-28 to 2008-01-01; source msha-controller-operator-history
- **controller_controls_operator:** Danny  Caldwell  et al → Bluebird Stone; 2002-10-28 to 2008-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Danny  Caldwell  et al → HILLTOP MINE; 2007-12-19 to 2016-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Bluebird Stone → HILLTOP MINE; 2008-01-02 to 2026-04-12; source msha-controller-operator-history
- **controller_controls_operator:** Danny  Caldwell  et al → Bluebird Stone; 2008-01-02 to 2016-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Tommy  Caldwell  et al → Bluebird Stone; 2008-01-02 to 2016-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Tommy  Caldwell → HILLTOP MINE; 2016-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tommy  Caldwell → Bluebird Stone; 2016-02-01 to 2026-04-12; source msha-controller-operator-history
- **operator_operates_mine:** TerraCore Materials, LLC → HILLTOP MINE; 2026-04-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael Chad  Robinson et al → HILLTOP MINE; 2026-04-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael Chad  Robinson et al → TerraCore Materials, LLC; 2026-04-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mason  Warren et al → TerraCore Materials, LLC; 2026-04-13 to current/open; source msha-controller-operator-history