List of scripts with no ISO 15924 code

The following writing scripts have not been allocated an ISO 15924 code.
 * APL
 * Gugyeol
 * Gupta script
 * iConji
 * Laṇḍā scripts
 * Quikscript
 * Romanian transitional alphabet
 * Szarvas inscription
 * Teeline Shorthand
 * Tironian notes
 * Great Lakes Algonquian syllabics
 * fictional constructed writing systems (Klingon, etc.)