Companies (to include the DTCC) have the right to privacy much like individuals do. Joe Public cannot legally gain access to all your personal and trading records just because he thinks he might be able to show somewhere in them that you're a terrorist or a crook. Similarly, CMKX Shareholders (Joe Public) are not entitled to see the DTCC's private records to check whether their made-up opinions are true.
If you have an ongoing legal proceeding, then you can go the subpoena or warrant route to seek specific records for your case. Courts do not like entities using them for fishing expeditions.
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"We simply attempt to be fearful when others are greedy and to be greedy only when others are fearful."
-- Warren Buffett