# Relationship history for MSHA mine 3900677

Current hierarchy: **David  Bitterman → Bitterman Sand Pit → BITTERMAN SAND 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

- **operator_operates_mine:** Harlan A Hieb → BITTERMAN SAND PIT; 1950-01-01 to 1993-08-03; source msha-controller-operator-history
- **controller_controls_mine:** Harlan A  Hieb → BITTERMAN SAND PIT; 1950-01-01 to 1993-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Harlan A  Hieb → Harlan A Hieb; 1950-01-01 to 1993-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Bitterman Sand Pit → BITTERMAN SAND PIT; 1993-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David  Bitterman  et al → BITTERMAN SAND PIT; 1993-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David  Bitterman  et al → Bitterman Sand Pit; 1993-08-04 to current/open; source msha-controller-operator-history