It means original group of investment instruments which are blocked in the same way. This identifier is the same as the right number in case the instruments are blocked with 1 right only (i.e. in the 1st level only). It is possible to determine the way the asset instruments are blocked according beginning of the group ID. If the group ID begins with:
60 - 67: instruments are blocked with 1 right only (pledge, co-ownership, yields transfer);
68: instruments are blocked with at least 2 rights at the same time;
69: instruments are blocked with 1 PPN only.
IDSK = 0 for instruments on sub-account = 02 (free instruments).