DTCC Rollout of Client interface - the change is designed to provide Members with a more enhanced, streamlined, and secure way to view upcoming voluntary corporate actions as well as optional dividends for their CNSยฎ positions

Source

I believe CNS positions refers to:

CNS short positions, which represent securities owed by Members to NSCC, are compared against their DTC accounts to determine availability. If shares are available, they are delivered from the Member's account at DTC to NSCC's account at DTC to cover Members' short obligations to CNS.

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