diff --git a/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice b/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
index 153810cd5c7e0a4d2bfd27a3e5238ef716d63adf..232c84aad37ab7c9e1ce1796c77b7b846c6d31d3 100644
--- a/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
+++ b/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
@@ -59,8 +59,8 @@ module armarx
         };
         class GraspCandidateExecutionHints
         {
-            ApertureType preshape;
-            ApproachType approach;
+            ApertureType preshape = AnyAperture;
+            ApproachType approach = AnyApproach;
             string graspTrajectoryName;
         };
         class GraspCandidateReachabilityInfo
@@ -86,7 +86,7 @@ module armarx
 
             float graspSuccessProbability;
 
-            ObjectTypeEnum objectType;
+            ObjectTypeEnum objectType = AnyObject;
             int groupNr = -1; // used to match candidates that belog together, e.g. from the same object or point cloud segment
             string providerName;