diff --git a/src/Diagnostics.AIProjects/SearchAPI/requirements.txt b/src/Diagnostics.AIProjects/SearchAPI/requirements.txt
index 4c9611fd4..795380f44 100644
--- a/src/Diagnostics.AIProjects/SearchAPI/requirements.txt
+++ b/src/Diagnostics.AIProjects/SearchAPI/requirements.txt
@@ -1,6 +1,6 @@
 Flask==1.1.1
 flask_cors==3.0.7
-nltk==3.4
+nltk==3.6.6
 gensim==3.7.2
 requests==2.18.4
 pyjwt==1.7.1