During recovery and processing, a tissue lot is assigned a unique identifier and kept in a held, non-distributable status while samples drawn from that lot are sent out for testing, most commonly sterility testing. This separation exists so that material cannot reach a clinic before its test results and paperwork are complete.
Release happens only when test results come back within the supplier's defined limits and the associated paperwork has been reviewed. A lot remains quarantined until testing is complete and release criteria are met; ask how nonconforming lots are handled. The gap between a lot's recovery date and its release date is part of the record a buyer can request for a specific shipment.
For a clinic, verifying this step means requesting the lot-specific release record, since testing itself happens at the supplier's labs. Ask a prospective vendor whether they can produce the release date and underlying test report tied to the lot number on your shipment, not just a general statement that testing is performed. A supplier that cannot produce lot-specific release records is a documentation gap worth flagging during vendor evaluation.
Lot-specific release records are direct evidence that a shipment was not distributed before its required testing was complete, which is a reasonable starting point for a purchasing or compliance file.