diff --git a/include/boost/regex/v4/cpp_regex_traits.hpp b/include/boost/regex/v4/cpp_regex_traits.hpp
index cbd699da..6896e60f 100644
--- a/include/boost/regex/v4/cpp_regex_traits.hpp
+++ b/include/boost/regex/v4/cpp_regex_traits.hpp
@@ -509,8 +509,10 @@ typename cpp_regex_traits_implementation<charT>::string_type
       case sort_delim:
             // get a regular sort key, and then truncate everything after the delim:
             result.assign(this->m_pcollate->transform(p1, p2));
+            if(result.size() && (result[0] == m_collate_delim))
+               break;
             std::size_t i;
-            for(i = 0; i < result.size(); ++i)
+            for(i = 1; i < result.size(); ++i)
             {
                if(result[i] == m_collate_delim)
                   break;
diff --git a/src/c_regex_traits.cpp b/src/c_regex_traits.cpp
index 5cac4a44..a33f7b17 100644
--- a/src/c_regex_traits.cpp
+++ b/src/c_regex_traits.cpp
@@ -91,6 +91,8 @@ c_regex_traits<char>::string_type BOOST_REGEX_CALL c_regex_traits<char>::transfo
    case ::boost::re_detail::sort_delim:
          // get a regular sort key, and then truncate everything after the delim:
          result = transform(p1, p2);
+         if(result.size() && (result[0] == s_delim))
+            break;
          std::size_t i;
          for(i = 0; i < result.size(); ++i)
          {
diff --git a/src/wc_regex_traits.cpp b/src/wc_regex_traits.cpp
index f86c5122..2b3764e3 100644
--- a/src/wc_regex_traits.cpp
+++ b/src/wc_regex_traits.cpp
@@ -83,6 +83,8 @@ c_regex_traits<wchar_t>::string_type BOOST_REGEX_CALL c_regex_traits<wchar_t>::t
    case ::boost::re_detail::sort_delim:
          // get a regular sort key, and then truncate everything after the delim:
          result = c_regex_traits<wchar_t>::transform(&*result.begin(), &*result.begin() + result.size());
+         if(result.size() && (result[0] == s_delim))
+            break;
          std::size_t i;
          for(i = 0; i < result.size(); ++i)
          {