diff --git a/src/main/antlr4/de/dhbwstuttgart/input/parser/ConstraintSet.g4 b/src/main/antlr4/de/dhbwstuttgart/input/parser/ConstraintSet.g4
index 3f17519..9a49e77 100644
--- a/src/main/antlr4/de/dhbwstuttgart/input/parser/ConstraintSet.g4
+++ b/src/main/antlr4/de/dhbwstuttgart/input/parser/ConstraintSet.g4
@@ -17,7 +17,7 @@ tph : '_' IDENTIFIER;
 namedType : IDENTIFIER params?;
 params : '<' type (',' type)* '>';
 
-IDENTIFIER: [0-9A-Za-z.]+;
+IDENTIFIER: [0-9A-Za-z.$[;][0-9A-Za-z.$[;_]*;
 
 NEWLINE : [\r\n]+ -> skip;
 WS: [ \t] -> skip ;
\ No newline at end of file