diff --git a/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java b/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
index ffae2c9b..68e8befa 100644
--- a/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
+++ b/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
@@ -508,6 +508,7 @@ public class JavaTXCompiler {
 			logFile.write("FC:\\" + finiteClosure.toString() + "\n");
 			for (SourceFile sf : this.sourceFiles.values()) {
 				logFile.write(ASTTypePrinter.print(sf));
+				System.out.println(ASTTypePrinter.print(sf));
 			}
 			logFile.flush();
 
diff --git a/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java b/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
index b1cae201..6fc57a7f 100644
--- a/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
+++ b/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
@@ -607,8 +607,8 @@ public class TypeUnifyTask extends RecursiveTask<Set<Set<UnifyPair>>>  {
 			for (UnifyPair ele : nextSetasList.get(0)) {//check ob a <. ty base oder ob Ueberladung
 				sameBase = sameBase && ele.getBasePair() != null && ele.getBasePair().equals(fstBasePair);
 			}
-			if (sameBase) {
-				Optional<Integer> xi = nextSetasList.stream().map(x -> x.stream().filter(y -> y.getLhsType() instanceof PlaceholderType)
+			if (sameBase) {                                                                                                                 //angefuegt PL 2020-02-30
+				Optional<Integer> xi = nextSetasList.stream().map(x -> x.stream().filter(y -> (y.getLhsType() instanceof PlaceholderType && !(y.getRhsType() instanceof PlaceholderType)))
 						.filter(z -> ((PlaceholderType)z.getLhsType()).getVariance() != 0)
 						.map(c -> ((PlaceholderType)c.getLhsType()).getVariance())
 						.reduce((a,b)-> {if (a==b) return a; else return 0; })) //2 kommt insbesondere bei Oder-Constraints vor