diff --git a/sdks/java/io/expansion-service/build.gradle b/sdks/java/io/expansion-service/build.gradle
index a0c2930c1ff9..8d58bdb453e4 100644
--- a/sdks/java/io/expansion-service/build.gradle
+++ b/sdks/java/io/expansion-service/build.gradle
@@ -35,6 +35,13 @@ applyJavaNature(
 configurations.runtimeClasspath {
   // Pin kafka-clients version due to <3.4.0 missing auth callback classes.
   resolutionStrategy.force 'org.apache.kafka:kafka-clients:3.9.0'
+  // Pin httpclient5 to 5.4.3 to fix OAUTHBEARER auth regression (#39789)
+  // httpclient5 5.5 breaks google-auth-library-oauth2-http transport layer
+  resolutionStrategy.force 'org.apache.httpcomponents.client5:httpclient5:5.4.3'
+  resolutionStrategy.force 'org.apache.httpcomponents.client5:httpclient5-fluent:5.4.3'
+  resolutionStrategy.force 'org.apache.httpcomponents.core5:httpcore5:5.2.5'
+  resolutionStrategy.force 'org.apache.httpcomponents.core5:httpcore5-h2:5.2.5'
+
   // force parquet-avro:1.15.2 to fix CVE-2025-46762
   resolutionStrategy.force 'org.apache.parquet:parquet-avro:1.15.2'