diff --git a/processor/src/main/java/org/mapstruct/ap/model/IterableMappingMethod.java b/processor/src/main/java/org/mapstruct/ap/model/IterableMappingMethod.java
index d4a7bdb4f..2daf00136 100644
--- a/processor/src/main/java/org/mapstruct/ap/model/IterableMappingMethod.java
+++ b/processor/src/main/java/org/mapstruct/ap/model/IterableMappingMethod.java
@@ -179,6 +179,9 @@ public class IterableMappingMethod extends MappingMethod {
         }
         if ( ( factoryMethod == null ) && ( !isExistingInstanceMapping() ) ) {
             types.addAll( getReturnType().getImportTypes() );
+            if ( getReturnType().getImplementationType() != null ) {
+                types.addAll( getReturnType().getImplementationType().getImportTypes() );
+            }
         }
         return types;
     }
diff --git a/processor/src/main/java/org/mapstruct/ap/model/MapMappingMethod.java b/processor/src/main/java/org/mapstruct/ap/model/MapMappingMethod.java
index c4e8065bc..37c3ad15c 100644
--- a/processor/src/main/java/org/mapstruct/ap/model/MapMappingMethod.java
+++ b/processor/src/main/java/org/mapstruct/ap/model/MapMappingMethod.java
@@ -217,6 +217,9 @@ public class MapMappingMethod extends MappingMethod {
         }
         if ( ( factoryMethod == null ) && ( !isExistingInstanceMapping() ) ) {
             types.addAll( getReturnType().getImportTypes() );
+            if ( getReturnType().getImplementationType() != null ) {
+                types.addAll( getReturnType().getImplementationType().getImportTypes() );
+            }
         }
 
         return types;
diff --git a/processor/src/main/java/org/mapstruct/ap/model/common/Type.java b/processor/src/main/java/org/mapstruct/ap/model/common/Type.java
index 31074d036..1b1b397c0 100644
--- a/processor/src/main/java/org/mapstruct/ap/model/common/Type.java
+++ b/processor/src/main/java/org/mapstruct/ap/model/common/Type.java
@@ -268,10 +268,6 @@ public class Type extends ModelElement implements Comparable<Type> {
 
         result.add( this );
 
-        if ( implementationType != null ) {
-            result.addAll( implementationType.getImportTypes() );
-        }
-
         if ( componentType != null ) {
             result.addAll( componentType.getImportTypes() );
         }