There is a TLNIIS macro setting of PGMCUST.
Both in the SETSYS, and SETENV.
You can set it at the Environment level(such as CICS,IMS,BATCH), or the
System level, which is any environment.
PGMCUST=NONE/ANY/( LIST CUSTOM EXITS THAT MAY BE REFERENCED)
LIST CUSTOM EXITS THAT MAY BE REFERENCED IN PROGRAM GENERATION.
"NONE" INDICATES THAT NO PGMCUST CUSTOM CODE EXIT POINTS MAY BE USED;
"ANY" INDICATES ANY OF THEM MAY BE REFERENCED.