diff --git a/google-cloud-firestore/clirr-ignored-differences.xml b/google-cloud-firestore/clirr-ignored-differences.xml
new file mode 100644
index 000000000..ea94bf5b0
--- /dev/null
+++ b/google-cloud-firestore/clirr-ignored-differences.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Copyright 2020 Google LLC
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~       http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<!-- see http://www.mojohaus.org/clirr-maven-plugin/examples/ignored-differences.html -->
+<differences>
+  <!-- TODO: Remove after release of 1.33.0 -->
+  <difference>
+    <differenceType>7012</differenceType>
+    <className>com/google/cloud/firestore/Firestore</className>
+    <method>com.google.api.core.ApiFuture runAsyncTransaction(*)</method>
+  </difference>
+</differences>