diff --git os_exchange_data_provider_aurax11.cc os_exchange_data_provider_aurax11.cc
index 6048670..b37f4bf 100644
--- os_exchange_data_provider_aurax11.cc
+++ os_exchange_data_provider_aurax11.cc
@@ -158,7 +158,8 @@ void OSExchangeDataProviderAuraX11::SetURL(const GURL& url,
                        mem);
 
     // Set a string fallback as well.
-    SetString(spec);
+    if (!HasString())
+      SetString(spec);
 
     // Return early if this drag already contains file contents (this implies
     // that file contents must be populated before URLs). Nautilus (and possibly