diff --git a/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java b/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
index e264f0f4..4710a02e 100644
--- a/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
+++ b/src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java
@@ -188,7 +188,7 @@ public class JavaTXCompiler {
 				cl.getMethods().add(new Method(m.modifier, m.name, m.getReturnType().acceptTV(new TypeExchanger(gtvs)), newParaList, m.block,
 							  //new GenericDeclarationList(newGenericsList, ((GenericDeclarationList)m.getGenerics()).getOffset()), 
 						(GenericDeclarationList)m.getGenerics(),
-						m.getOffset()));
+						m.getOffset(), true));
 			}
 				
 		}
diff --git a/src/main/java/de/dhbwstuttgart/typeinference/unify/RuleSet.java b/src/main/java/de/dhbwstuttgart/typeinference/unify/RuleSet.java
index e52b3cd0..c7c6c6cc 100644
--- a/src/main/java/de/dhbwstuttgart/typeinference/unify/RuleSet.java
+++ b/src/main/java/de/dhbwstuttgart/typeinference/unify/RuleSet.java
@@ -679,8 +679,8 @@ public class RuleSet implements IRuleSet{
 				result = result.stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(ArrayList::new));
 				result1 = result1.stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(LinkedList::new));
 				
-				Function<? super Set<UnifyPair>,? extends Constraint<UnifyPair>> applyUni = b -> b.stream().map(
-						x -> uni.apply(pair,x)).collect(Collectors.toCollection(Constraint::new));
+				Function<? super Constraint<UnifyPair>,? extends Constraint<UnifyPair>> applyUni = b -> b.stream().map(
+						x -> uni.apply(pair,x)).collect(Collectors.toCollection(() -> new Constraint<UnifyPair>(b.isInherited())));
 				List<Set<Set<UnifyPair>>> oderConstraintsRet = new ArrayList<>();
 				for(Set<Constraint<UnifyPair>> oc : oderConstraints) {
 					//Set<Set<UnifyPair>> ocRet = new HashSet<>();
@@ -689,7 +689,7 @@ public class RuleSet implements IRuleSet{
 						oderConstraintsRet.add(csRet);
 					//}
 				}
-				oderConstraints.replaceAll(oc -> oc.stream().map(applyUni).collect(Collectors.toCollection(Constraint::new)));
+				oderConstraints.replaceAll(oc -> oc.stream().map(applyUni).collect(Collectors.toCollection(HashSet::new)));
 				/*
 						oderConstraints = oderConstraints.stream().map(
 						a -> a.stream().map(applyUni
diff --git a/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java b/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
index 8ebce509..19a6c48b 100644
--- a/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
+++ b/src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTask.java
@@ -1364,7 +1364,8 @@ public class TypeUnifyTask extends RecursiveTask<Set<Set<UnifyPair>>>  {
 							while (nextSetasListIt.hasNext()) {
 								Set<UnifyPair> a_next = nextSetasListIt.next();
 								if (a_new.equals(a_next) || 
-										(oup.compare(a_new, a_next) == -1)) {
+										((oup.compare(a_new, a_next) == -1) &&
+												(!oderConstraint || ((Constraint)a_new).isInherited()))){
 									writeLog("Removed: " + a_next.toString());
 									nextSetasList.remove(a_next); //PL geaendert 2019-01-09
 								}
@@ -1383,7 +1384,8 @@ public class TypeUnifyTask extends RecursiveTask<Set<Set<UnifyPair>>>  {
 							while (nextSetasListIt.hasNext()) {
 								Set<UnifyPair> a_next = nextSetasListIt.next();
 								if (a_new.equals(a_next) || 
-										(oup.compare(a_new, a_next) == 1)) {
+										((oup.compare(a_new, a_next) == 1) &&
+												(!oderConstraint || ((Constraint)a_next).isInherited()))){
 									writeLog("Removed: " + a_next.toString());
 									nextSetasList.remove(a_next);
 								}