diff --git a/clients/google-api-services-pubsub/v1/2.0.0/README.md b/clients/google-api-services-pubsub/v1/2.0.0/README.md
index 5c97dffc758..37ec1e0d6f4 100644
--- a/clients/google-api-services-pubsub/v1/2.0.0/README.md
+++ b/clients/google-api-services-pubsub/v1/2.0.0/README.md
@@ -22,7 +22,7 @@ Add the following lines to your `pom.xml` file:
     <dependency>
       <groupId>com.google.apis</groupId>
       <artifactId>google-api-services-pubsub</artifactId>
-      <version>v1-rev20260924-2.0.0</version>
+      <version>v1-rev20261006-2.0.0</version>
     </dependency>
   </dependencies>
 </project>
@@ -35,7 +35,7 @@ repositories {
   mavenCentral()
 }
 dependencies {
-  implementation 'com.google.apis:google-api-services-pubsub:v1-rev20260924-2.0.0'
+  implementation 'com.google.apis:google-api-services-pubsub:v1-rev20261006-2.0.0'
 }
 ```
 
diff --git a/clients/google-api-services-pubsub/v1/2.0.0/com/google/api/services/pubsub/model/DelimitedKey.java b/clients/google-api-services-pubsub/v1/2.0.0/com/google/api/services/pubsub/model/DelimitedKey.java
index 6eeaaf1f479..b2c975d5911 100644
--- a/clients/google-api-services-pubsub/v1/2.0.0/com/google/api/services/pubsub/model/DelimitedKey.java
+++ b/clients/google-api-services-pubsub/v1/2.0.0/com/google/api/services/pubsub/model/DelimitedKey.java
@@ -38,7 +38,7 @@ public final class DelimitedKey extends com.google.api.client.json.GenericJson {
   private java.lang.String delimiter;
 
   /**
-   * Optional. The key fields to construct from the row key. The fields must be present in the
+   * Required. The key fields to construct from the row key. The fields must be present in the
    * message as a top-level field, i.e. JSON path expressions will not traverse into nested objects.
    * The value may be {@code null}.
    */
@@ -95,7 +95,7 @@ public DelimitedKey encodeDelimiter(byte[] delimiter) {
   }
 
   /**
-   * Optional. The key fields to construct from the row key. The fields must be present in the
+   * Required. The key fields to construct from the row key. The fields must be present in the
    * message as a top-level field, i.e. JSON path expressions will not traverse into nested objects.
    * @return value or {@code null} for none
    */
@@ -104,7 +104,7 @@ public java.util.List<java.lang.String> getKeyFields() {
   }
 
   /**
-   * Optional. The key fields to construct from the row key. The fields must be present in the
+   * Required. The key fields to construct from the row key. The fields must be present in the
    * message as a top-level field, i.e. JSON path expressions will not traverse into nested objects.
    * @param keyFields keyFields or {@code null} for none
    */
diff --git a/clients/google-api-services-pubsub/v1/2.0.0/pom.xml b/clients/google-api-services-pubsub/v1/2.0.0/pom.xml
index 282ad8576e3..e38e69eb40f 100644
--- a/clients/google-api-services-pubsub/v1/2.0.0/pom.xml
+++ b/clients/google-api-services-pubsub/v1/2.0.0/pom.xml
@@ -8,8 +8,8 @@
 
   <groupId>com.google.apis</groupId>
   <artifactId>google-api-services-pubsub</artifactId>
-  <version>v1-rev20260924-2.0.0</version>
-  <name>Cloud Pub/Sub API v1-rev20260924-2.0.0</name>
+  <version>v1-rev20261006-2.0.0</version>
+  <name>Cloud Pub/Sub API v1-rev20261006-2.0.0</name>
   <packaging>jar</packaging>
 
   <inceptionYear>2011</inceptionYear>
diff --git a/clients/google-api-services-pubsub/v1/README.md b/clients/google-api-services-pubsub/v1/README.md
index 5c97dffc758..37ec1e0d6f4 100644
--- a/clients/google-api-services-pubsub/v1/README.md
+++ b/clients/google-api-services-pubsub/v1/README.md
@@ -22,7 +22,7 @@ Add the following lines to your `pom.xml` file:
     <dependency>
       <groupId>com.google.apis</groupId>
       <artifactId>google-api-services-pubsub</artifactId>
-      <version>v1-rev20260924-2.0.0</version>
+      <version>v1-rev20261006-2.0.0</version>
     </dependency>
   </dependencies>
 </project>
@@ -35,7 +35,7 @@ repositories {
   mavenCentral()
 }
 dependencies {
-  implementation 'com.google.apis:google-api-services-pubsub:v1-rev20260924-2.0.0'
+  implementation 'com.google.apis:google-api-services-pubsub:v1-rev20261006-2.0.0'
 }
 ```