# Relationship history for MSHA mine 0600790

Current hierarchy: **Matthew M  Brennan; Eric T  Brennan → JOHN J. BRENNAN CONST. CO. INC. → PORTABLE 300**

- 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:** David R  Brennan  et al → PORTABLE 300; 1985-01-01 to 2024-03-31; source msha-controller-operator-history
- **operator_operates_mine:** John J. Brennan Const. Co. Inc. → PORTABLE 300; 2016-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David R  Brennan  et al → John J. Brennan Const. Co. Inc.; 2016-02-17 to 2024-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Matthew M  Brennan → PORTABLE 300; 2024-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matthew M  Brennan → John J. Brennan Const. Co. Inc.; 2024-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eric T  Brennan → John J. Brennan Const. Co. Inc.; 2024-04-01 to current/open; source msha-controller-operator-history