diff --git a/coding/trie_builder.hpp b/coding/trie_builder.hpp
index e057d1df7d..f14461284c 100644
--- a/coding/trie_builder.hpp
+++ b/coding/trie_builder.hpp
@@ -250,7 +250,8 @@ void Build(SinkT & sink, IterT const beg, IterT const end, EdgeBuilderT const &
   for (IterT it = beg; it != end; ++it)
   {
     ElementT e = *it;
-    if (e == prevE) continue;
+    if (e == prevE && it != beg)
+      continue;
 
     TrieChar const * const pKeyData = e.GetKeyData();
     TrieString key(pKeyData, pKeyData + e.GetKeySize());