diff --git a/extraction/named_entity/Chemlistem/requirements.txt b/extraction/named_entity/Chemlistem/requirements.txt
index 4b41e184..47b93d15 100644
--- a/extraction/named_entity/Chemlistem/requirements.txt
+++ b/extraction/named_entity/Chemlistem/requirements.txt
@@ -21,7 +21,7 @@ numpy==1.16.3
 pathlib==1.0.1
 plac==0.9.6
 preshed==1.0.1
-protobuf==3.7.1
+protobuf==3.18.3
 PyYAML==5.1
 regex==2017.11.9
 requests==2.21.0