diff --git a/gson/src/main/java/com/google/gson/JsonIOException.java b/gson/src/main/java/com/google/gson/JsonIOException.java
index 1e6612d3..a05975db 100644
--- a/gson/src/main/java/com/google/gson/JsonIOException.java
+++ b/gson/src/main/java/com/google/gson/JsonIOException.java
@@ -24,6 +24,8 @@ package com.google.gson;
  */
 public final class JsonIOException extends JsonParseException {
 
+  private static final long serialVersionUID = 1L;
+
   public JsonIOException(String msg) {
     super(msg);
   }
diff --git a/gson/src/main/java/com/google/gson/JsonSyntaxException.java b/gson/src/main/java/com/google/gson/JsonSyntaxException.java
index 47f1b14f..23447e40 100644
--- a/gson/src/main/java/com/google/gson/JsonSyntaxException.java
+++ b/gson/src/main/java/com/google/gson/JsonSyntaxException.java
@@ -24,6 +24,8 @@ package com.google.gson;
  */
 public final class JsonSyntaxException extends JsonParseException {
 
+  private static final long serialVersionUID = 1L;
+
   public JsonSyntaxException(String msg) {
     super(msg);
   }