The PROPERTY_META_DATA_EXT structure defines a concrete type for the stamp of the last originating update to an attribute.

 typedef struct {
   DWORD dwVersion;
   DSTIME timeChanged;
   UUID uuidDsaOriginating;
   USN usnOriginating;

dwVersion: The version of the attribute values, starting at 1 and increasing by one with each originating update.

timeChanged: The time at which the originating update was performed.

uuidDsaOriginating: The invocationId of the DC that performed the originating update.

usnOriginating: The USN of the DC assigned to the originating update.