Biobanks require new governance models that address their ethical and regulatory challenges. One model relies on stewardship of specimens throughout their life course. Here, we discuss findings from our survey of 456 U.S. biobank managers that addressed whether and how biobanks steward their specimens. The findings reveal that most biobanks do not create ongoing relationships with contributors but do practice stewardship over storing and sharing of specimens. Biobanks now need guidance to fully articulate stewardship practices that ensure respect for contributors while facilitating research.