# Relationship history for MSHA mine 3608278

Current hierarchy: **Thomas J  Smith → T.J.S. Mining, Inc. → Darmac No. 3**

- 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:** AOI Coal Company → Darmac No. 3; 1987-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thomas J  Smith → Darmac No. 3; 1991-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Darmac Associates Corp → Darmac No. 3; 1991-09-01 to 1994-08-28; source msha-controller-operator-history
- **controller_controls_operator:** AOI Coal Company → Darmac Associates Corp; 1991-09-01 to 1994-08-28; source msha-controller-operator-history
- **operator_operates_mine:** T.J.S. Mining, Inc. → Darmac No. 3; 1994-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas J  Smith → T.J.S. Mining, Inc.; 1994-08-29 to current/open; source msha-controller-operator-history