diff --git a/source/Utils/include/FilterClusters.h b/source/Utils/include/FilterClusters.h
new file mode 100644
index 0000000..ab76767
--- /dev/null
+++ b/source/Utils/include/FilterClusters.h
@@ -0,0 +1,56 @@
+#pragma once
+
+#include <marlin/Processor.h>
+
+//#include <ACTSTracking/GeometryIdMappingTool.hxx>
+
+namespace TrackPerf
+{
+}
+
+class FilterClusters : public marlin::Processor
+{
+public:
+   virtual Processor* newProcessor() { return new FilterClusters ; }
+
+   FilterClusters(const FilterClusters &) = delete ;
+   FilterClusters& operator =(const FilterClusters &) = delete ;
+   FilterClusters() ;
+
+   /** Called at the begin of the job before anything is read.
+    * Use to initialize the processor, e.g. book histograms.
+    */
+   virtual void init() ;
+
+   /** Called for every run.
+    */
+   virtual void processRunHeader( LCRunHeader* run ) ;
+
+   /** Called for every event - the working horse.
+    */
+   virtual void processEvent(LCEvent* evt) ;
+
+
+   /** Called after data processing for clean up.
+    */
+   virtual void end() ;
+
+private:
+   //! Input track collection
+   std::string _InTrackerHitCollection {};
+   std::string _InRelationCollection {};
+
+   //! Output track collection
+   std::string _OutTrackerHitCollection {};
+   std::string _OutRelationCollection {};
+
+   //! Ranges for theta
+   std::vector<std::string> _ThetaRanges;
+
+   //! Cut-offs for cluster size in various theta ranges
+   std::vector<std::string> _ClusterSize;
+
+   //! Layers to be filtered
+   std::vector<std::string> _Layers;
+
+};
diff --git a/source/Utils/src/FilterClusters.cc b/source/Utils/src/FilterClusters.cc
new file mode 100644
index 0000000..1797855
--- /dev/null
+++ b/source/Utils/src/FilterClusters.cc
@@ -0,0 +1,184 @@
+#include "FilterClusters.h"
+
+#include <math.h>
+
+#include <DD4hep/Detector.h>
+
+#include <EVENT/Track.h>
+#include <EVENT/TrackerHit.h>
+#include <EVENT/SimTrackerHit.h>
+#include <IMPL/LCCollectionVec.h>
+#include <UTIL/LCTrackerConf.h>
+#include <UTIL/CellIDDecoder.h>
+#include <IMPL/LCRelationImpl.h>
+
+#include <marlin/AIDAProcessor.h>
+
+#include <AIDA/ITree.h>
+
+#include "marlin/VerbosityLevels.h"
+
+
+FilterClusters aFilterClusters ;
+
+FilterClusters::FilterClusters()
+  : Processor("FilterClusters")
+{
+  // modify processor description
+  _description = "FilterClusters processor filters a collection of tracker hits based on cluster size and outputs a filtered collection";
+
+  // register steering parameters: name, description, class-variable, default value
+  registerProcessorParameter("ThetaRanges",
+         "Divide theta into bins for different cluster size cuts",
+         _ThetaRanges, 
+         {}
+          );
+  registerProcessorParameter("ClusterSize",
+		  	 "Maximum cluster size for each theta range",
+			   _ClusterSize,
+			   {}
+			    );  
+  registerProcessorParameter("Layers",
+		  	 "Layers to be filtered",
+			   _Layers,
+			   {}
+			    );  
+  registerInputCollection( LCIO::TRACKERHIT,
+		  	 "InTrackerHitCollection" ,
+			   "Name of the input tracker hit collection",
+			   _InTrackerHitCollection,
+		     _InTrackerHitCollection
+		 	    );
+
+  registerInputCollection( LCIO::LCRELATION,
+		     "InRelationCollection" ,
+			   "Name of the input relation collection",
+			   _InRelationCollection,
+		     _InRelationCollection
+		 	    );
+
+  registerOutputCollection( LCIO::TRACKERHIT,
+		  	 "OutTrackerHitCollection" ,
+			   "Name of output tracker hit collection",
+			   _OutTrackerHitCollection,
+			   std::string("FilteredVBTrackerHits")
+			    );
+
+    registerOutputCollection( LCIO::LCRELATION,
+		  	 "OutRelationCollection" ,
+			   "Name of output relation collection",
+			   _OutRelationCollection,
+			   std::string("FilteredVBTrackerHitsRelations")
+			    );
+
+}
+
+void FilterClusters::init()
+{
+  // Print the initial parameters
+  printParameters() ;
+}
+
+void FilterClusters::processRunHeader( LCRunHeader* /*run*/)
+{ }
+
+void FilterClusters::processEvent( LCEvent * evt )
+{
+  // Make the output track collection
+  LCCollectionVec *OutTrackerHitCollection = new LCCollectionVec(LCIO::TRACKERHIT);
+  OutTrackerHitCollection->setSubset(true);
+  LCCollectionVec *OutRelationCollection   = new LCCollectionVec(LCIO::LCRELATION);
+  OutRelationCollection->setSubset(true);
+
+  // Get input collection
+  LCCollection* InTrackerHitCollection  = evt->getCollection(_InTrackerHitCollection);
+  LCCollection* InRelationCollection    = evt->getCollection(_InRelationCollection);
+
+  if( InTrackerHitCollection->getTypeName() != lcio::LCIO::TRACKERHITPLANE )
+    { throw EVENT::Exception( "Invalid collection type: " + InTrackerHitCollection->getTypeName() ) ; }
+    streamlog_out(DEBUG0) << "Wrong collection type for TrackerHitCollection. \n";
+  if( InRelationCollection->getTypeName() != lcio::LCIO::LCRELATION )
+    { throw EVENT::Exception( "Invalid collection type: " + InRelationCollection->getTypeName() ) ; }
+    streamlog_out(DEBUG0) << "Wrong collection type for InRelationCollection. \n";
+
+
+  streamlog_out(DEBUG0) << "Number of Elements in VB Tracker Hits Collection: " << InTrackerHitCollection->getNumberOfElements() <<std::endl;
+  // Filter
+  for(int i=0; i<InTrackerHitCollection->getNumberOfElements(); ++i) //loop through all hits
+    {
+      streamlog_out(DEBUG0) << "Loop over hits opened. \n";
+      EVENT::TrackerHit *trkhit=static_cast<EVENT::TrackerHit*>(InTrackerHitCollection->getElementAt(i)); //define trkhit var, pointer to i'th element of tracker hits
+      EVENT::LCRelation *rel=static_cast<EVENT::LCRelation*>(InRelationCollection->getElementAt(i));
+      
+      //Calculating theta 
+      float x = trkhit->getPosition()[0];
+      float y = trkhit->getPosition()[1];
+      float z = trkhit->getPosition()[2];
+      float r = sqrt(pow(x,2)+pow(y,2));
+      float incidentTheta = std::atan(r/z); 
+
+      if(incidentTheta<0)
+        incidentTheta += M_PI;
+
+      //Calculating cluster size
+      const lcio::LCObjectVec &rawHits = trkhit->getRawHits();
+      float max = -1000000;
+      float min = 1000000;
+      for (size_t j=0; j<rawHits.size(); ++j) {
+        lcio::SimTrackerHit *hitConstituent = dynamic_cast<lcio::SimTrackerHit*>( rawHits[j] );
+        const double *localPos = hitConstituent->getPosition();
+        x = localPos[0];
+        y = localPos[1];
+        if (y < min){
+          min = y;
+        }
+        else if (y > max){
+          max = y;          
+        }
+      }
+      float cluster_size = (max - min)+1;
+
+      //Get hit subdetector/layer 
+      std::string _encoderString = lcio::LCTrackerCellID::encoding_string();
+      UTIL::CellIDDecoder<lcio::TrackerHit> decoder(_encoderString);
+      uint32_t systemID = decoder(trkhit)["system"];
+      uint32_t layerID = decoder(trkhit)["layer"];
+      bool filter_layer = false;
+      for (size_t j=0; j<_Layers.size(); ++j){
+        if (layerID == std::stof(_Layers[j])) {
+          filter_layer = true;
+        }
+      }
+      streamlog_out(DEBUG0) << "Filter layer: " << filter_layer << std::endl;
+      
+      for (size_t j=0; j<_ThetaRanges.size()-1; ++j) {
+        streamlog_out( DEBUG0 ) << "theta: " << incidentTheta << std::endl;
+        float min_theta = std::stof(_ThetaRanges[j]);
+        float max_theta = std::stof(_ThetaRanges[j+1]);
+        streamlog_out( DEBUG0 ) << "theta range: " << min_theta << ", " << max_theta << std::endl;
+
+        if(incidentTheta > min and incidentTheta <= max and not filter_layer){
+          streamlog_out( DEBUG0 ) << "theta in range" << std::endl;
+          streamlog_out( DEBUG0 ) << "cluster size cut off: " << _ClusterSize[j] << std::endl;
+          streamlog_out( DEBUG0 ) << "cluster size: " << cluster_size << std::endl;
+          if(cluster_size < std::stof(_ClusterSize[j])) {
+            streamlog_out( DEBUG0 ) << "cluster added" << std::endl;
+            OutTrackerHitCollection->addElement(trkhit); 
+            OutRelationCollection->addElement(rel); }
+          else {
+            streamlog_out( DEBUG0 ) << "cluster rejected" << std::endl;
+          }
+        }
+        else{
+          streamlog_out( DEBUG0 ) << "theta out of range or layer filtered" << std::endl;
+        }
+      }
+    }
+
+  // Save output track collection
+  evt->addCollection(OutTrackerHitCollection, _OutTrackerHitCollection); 
+  evt->addCollection(OutRelationCollection, _OutRelationCollection); 
+}
+
+void FilterClusters::end()
+{ }