diff --git a/modules/seq/base/src/hmm.cc b/modules/seq/base/src/hmm.cc
index fd953d5f5f5e5126864b373bc28e7a212118ae30..a89d3cf27b23613240d9ec5868cd8b6d9704ea5d 100644
--- a/modules/seq/base/src/hmm.cc
+++ b/modules/seq/base/src/hmm.cc
@@ -165,7 +165,7 @@ HMMPtr HMM::Extract(uint from, uint to){
     throw std::runtime_error("Second index must be bigger than first one!");
   }
 
-  if(to >= this->size()){
+  if(to > this->size()){
     throw std::runtime_error("Invalid index!");
   }