2.2.3 PidTagAccessControlListData Property
Type: PtypBinary ([MS-OXCDATA] section 2.11.1)
The PidTagAccessControlListData property ([MS-OXPROPS] section 2.506) contains a variable-length binary large object (BLOB) that constitutes a permissions list for a folder. This property is used when an ACL is copied from one folder to another.<2>
The client does not understand the data contained in the BLOB and does not try to use the data. The BLOB is only used to copy the ACL from one folder to another.