diff --git a/src/decoder.cpp b/src/decoder.cpp
index 06fb35b7..6368c77c 100644
--- a/src/decoder.cpp
+++ b/src/decoder.cpp
@@ -145,7 +145,7 @@ bool zmq::decoder_t::eight_byte_size_ready ()
 bool zmq::decoder_t::flags_ready ()
 {
     //  Store the flags from the wire into the message structure.
-    in_progress.set_flags (tmpbuf [0]);
+    in_progress.set_flags (tmpbuf [0] & msg_t::more);
 
     next_step (in_progress.data (), in_progress.size (),
         &decoder_t::message_ready);