diff --git a/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice b/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
index ca22ae16be0dc739d1c43c7722f587ec653f07d8..153810cd5c7e0a4d2bfd27a3e5238ef716d63adf 100644
--- a/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
+++ b/source/RobotAPI/interface/units/GraspCandidateProviderInterface.ice
@@ -87,6 +87,8 @@ module armarx
             float graspSuccessProbability;
 
             ObjectTypeEnum objectType;
+            int groupNr = -1; // used to match candidates that belog together, e.g. from the same object or point cloud segment
+            string providerName;
 
             GraspCandidateSourceInfo sourceInfo; // (optional)
             GraspCandidateExecutionHints executionHints; // (optional)