diff --git a/lib/st/README b/lib/st/README
index be865b8..5b5fdee 100644
--- a/lib/st/README
+++ b/lib/st/README
@@ -22,6 +22,10 @@
 specific language governing permissions and limitations
 under the License.
 
+Contains some contributions under the Thrift Software License.
+Please see doc/old-thrift-license.txt in the Thrift distribution for
+details.
+
 Library
 =======