diff --git a/unicodetools/src/main/java/org/unicode/idna/GenerateIdna.java b/unicodetools/src/main/java/org/unicode/idna/GenerateIdna.java
index 5a5414beb..f9ee6bcec 100644
--- a/unicodetools/src/main/java/org/unicode/idna/GenerateIdna.java
+++ b/unicodetools/src/main/java/org/unicode/idna/GenerateIdna.java
@@ -347,8 +347,9 @@ private static UnicodeMap<Row.R2<IdnaType, String>> createMappingTable(boolean S
                         .removeAll(properties.getSet("gc=Zl"))
                         .removeAll(properties.getSet("gc=Zp"))
                         .removeAll(properties.getSet("gc=Zs"))
-                        .removeAll(properties.getSet("Block=Ideographic_Description_Characters"))
-                        .remove(0x31EF) // an IDC added in 15.1 outside the full IDC block
+                        .removeAll(properties.getSet("IDS_Unary_Operator=true"))
+                        .removeAll(properties.getSet("IDS_Binary_Operator=true"))
+                        .removeAll(properties.getSet("IDS_Trinary_Operator=true"))
                         .removeAll(new UnicodeSet("[\\u0000-\\u007F]"))
                         // Add lowercase sharp s to the base valid set.
                         // Otherwise the new-in-15.1 baseMapping for capital sharp s