MDAC 2.5 SDK - OLE DB Programmer's Reference
Chapter 4: Rowsets
Methods that return row handles can take a negative count of requested rows. This means that the absolute count of rows is returned, beginning with the first specified row and then moving backward (that is, in decreasing order of row number). For example, the next fetch row in IRowset::GetNextRows or the bookmarked row in IRowsetLocate::GetRowsAt is the specified row, so those preceding it up to the absolute count are returned. This behavior is independent of skip (offset) counts, which also can be negative.