# Relationship history for MSHA mine 2601521

Current hierarchy: **Richard (Dick)  Merritt → Dick Merritt → T L Miller 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:** Northern Engineering Company → T L Miller Mine; 1980-02-01 to 1981-01-12; source msha-controller-operator-history
- **controller_controls_mine:** Crooks Charles V & Paul L Et Al → T L Miller Mine; 1980-02-01 to 1981-01-12; source msha-controller-operator-history
- **controller_controls_operator:** Crooks Charles V & Paul L Et Al → Northern Engineering Company; 1980-02-01 to 1981-01-12; source msha-controller-operator-history
- **operator_operates_mine:** Dick Merritt → T L Miller Mine; 1981-01-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard (Dick)  Merritt → T L Miller Mine; 1981-01-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard (Dick)  Merritt → Dick Merritt; 1981-01-13 to current/open; source msha-controller-operator-history