diff --git a/engine/pom.xml b/engine/pom.xml
index 5e0e9a0174..ce34b5e71c 100644
--- a/engine/pom.xml
+++ b/engine/pom.xml
@@ -19,7 +19,7 @@ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xs
     UTF-8</project.build.sourceEncoding>
     <java.version>1.8</java.version>
     <grpc.version>1.25.0</grpc.version>
-    <pb.version>3.11.1</pb.version>
+    <pb.version>3.11.3</pb.version>
     <micrometer.version>1.3.0</micrometer.version>
     <start-class>io.seldon.engine.App</start-class>
     <jaeger.version>1.0.0</jaeger.version>