# Relationship history for MSHA mine 3402131

Current hierarchy: **Tommy  Caldwell → BLUEBIRD STONE → KREBBS PIT**

- 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:** Danny  Caldwell  et al → KREBBS PIT; 2007-12-19 to 2016-01-31; source msha-controller-operator-history
- **operator_operates_mine:** BLUEBIRD STONE → KREBBS PIT; 2012-06-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Danny  Caldwell  et al → BLUEBIRD STONE; 2012-06-06 to 2016-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Tommy  Caldwell  et al → BLUEBIRD STONE; 2012-06-06 to 2016-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Tommy  Caldwell → KREBBS PIT; 2016-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tommy  Caldwell → BLUEBIRD STONE; 2016-02-01 to current/open; source msha-controller-operator-history