they keep it. that is why they said to send copies of evidence and not the originals because you wont get the originals back.
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Date Sent 09/18/2012 Date Received 09/21/12
Date of Biometrics: October 24, 2012
2nd RFE update: 03/18/13 Received: 03/21/13
(asking for BC, 07 residency & HS transcript)
Date of Approval: 07/09/13 Date EAD Received: 07/13/13