diff --git a/L1Trigger/CSCTriggerPrimitives/src/GEMCoPadProcessor.cc b/L1Trigger/CSCTriggerPrimitives/src/GEMCoPadProcessor.cc
index c82badf8808f9..218c9c4f098d5 100644
--- a/L1Trigger/CSCTriggerPrimitives/src/GEMCoPadProcessor.cc
+++ b/L1Trigger/CSCTriggerPrimitives/src/GEMCoPadProcessor.cc
@@ -27,6 +27,8 @@ GEMCoPadProcessor::GEMCoPadProcessor() : theRegion(1), theStation(1), theChamber
 void GEMCoPadProcessor::clear() { gemCoPadV.clear(); }
 
 std::vector<GEMCoPadDigi> GEMCoPadProcessor::run(const GEMPadDigiCollection* in_pads) {
+  clear();  
+    
   // Build coincidences
   for (auto det_range = in_pads->begin(); det_range != in_pads->end(); ++det_range) {
     const GEMDetId& id = (*det_range).first;