# Relationship history for MSHA mine 4406843

Current hierarchy: **Theodore  Yates → Har-Lee Coal Company Inc → Pillars No 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Thyssen Schachtbau Gmbh → Pillars No 1; 1982-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Theodore  Yates et al → Pillars No 1; 1989-02-21 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Betty B Coal Company Inc → Pillars No 1; 1996-07-01 to 1999-04-19; source msha-controller-operator-history
- **controller_controls_operator:** Thyssen Schachtbau Gmbh → Betty B Coal Company Inc; 1996-07-01 to 1999-04-19; source msha-controller-operator-history
- **operator_operates_mine:** Har-Lee Coal Company Inc → Pillars No 1; 1999-04-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Theodore  Yates et al → Har-Lee Coal Company Inc; 1999-04-20 to current/open; source msha-controller-operator-history