I understand DTCC custodian services like that :
1)Ensures availability of detailed information on every certificate2)Ensures availability of images of all certificates and documents held in custody via DTC`s imaging Fax/Email (IFE) system, or the Imaging Drop-Box Solution.
3)Deposits of securities are made using the Participants Browser System (PBS) function CUST, via a CCF deposit file transmission.Once the certificates arrive at DTC, a full examination of all certificates is performed, including a negotiability check and verification of data received from the depositing participant firm.
Maybe I missed something, but it looks that DTCC didn`t follow its own rules, but if different, maybe you could "teach" us about that specific part.
(www.dtcc.com/products/asset/services/custody.php)