diff --git a/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationAdapter.java b/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationAdapter.java
index a515c946f4..ce7e802fdb 100644
--- a/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationAdapter.java
+++ b/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationAdapter.java
@@ -37,7 +37,7 @@ public interface SerializationAdapter {
    * Latest version number. If version is not defined by the user, NullAway will use the
    * corresponding adapter to this version in its serialization.
    */
-  int LATEST_VERSION = 4;
+  int LATEST_VERSION = 3;
 
   /**
    * Returns header of "errors.tsv" which contains all serialized {@link ErrorInfo} reported by
@@ -87,8 +87,6 @@ static SerializationAdapter getAdapterForVersion(int version) {
             "Serialization version v2 is skipped and was used for an alpha version of the auto-annotator tool. Please use version 3 instead.");
       case 3:
         return new SerializationV3Adapter();
-      case 4:
-        return new SerializationV4Adapter();
       default:
         throw new RuntimeException(
             "Unrecognized NullAway serialization version: "
diff --git a/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationV4Adapter.java b/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationV4Adapter.java
deleted file mode 100644
index 543bb7fca0..0000000000
--- a/nullaway/src/main/java/com/uber/nullaway/fixserialization/adapters/SerializationV4Adapter.java
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * Copyright (c) 2024 Uber Technologies, Inc.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-package com.uber.nullaway.fixserialization.adapters;
-
-/**
- * Adapter for serialization version 4.
- *
- * <p>Updates to previous version (version 3):
- *
- * <ul>
- *   <li>Fixes are not serialized anymore in a separate file. Since the current version of error
- *       structure contains all the necessary information to recreate the fix, there is no need to
- *       serialize the fix separately.
- * </ul>
- */
-public class SerializationV4Adapter extends SerializationV3Adapter {
-
-  @Override
-  public int getSerializationVersion() {
-    return 4;
-  }
-}