diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 8e5dc2b4312b..372f74f4957d 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,7 +1,7 @@
 {
   "google-ads-ad_manager": "3.1.0",
   "google-ads-ad_manager+FILLER": "0.0.0",
-  "google-ads-ad_manager-v1": "3.2.0",
+  "google-ads-ad_manager-v1": "4.0.0",
   "google-ads-ad_manager-v1+FILLER": "0.0.0",
   "google-ads-data_manager": "0.3.0",
   "google-ads-data_manager+FILLER": "0.0.0",
diff --git a/google-ads-ad_manager-v1/CHANGELOG.md b/google-ads-ad_manager-v1/CHANGELOG.md
index 3907397ba963..70dd72b46471 100644
--- a/google-ads-ad_manager-v1/CHANGELOG.md
+++ b/google-ads-ad_manager-v1/CHANGELOG.md
@@ -1,5 +1,89 @@
 # Changelog
 
+### 4.0.0 (2026-05-12)
+
+### ⚠ BREAKING CHANGES
+
+* An existing value `DEMAND_SUBCHANNEL_ALL` is removed from enum `Dimension`
+* Changed field behavior for an existing field `display_name` in message `.google.ads.admanager.v1.Application`
+* Removed UNIFIED_PRICING_RULE_ID dimension
+* Removed UNIFIED_PRICING_RULE_NAME dimension
+* Remove unused AdManagerError type
+* New REQUIRED field `display_name` in message `.google.ads.admanager.v1.Label`
+* New REQUIRED field `types` in message `.google.ads.admanager.v1.Label`
+
+#### Features
+
+* A new field `app_store_display_name` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `app_store_id` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `app_stores` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `application_code` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `approval_status` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `archived` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `developer` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `download_url` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `free` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `platform` is added to message `.google.ads.admanager.v1.Application` 
+* A new field `webview_claiming_status` is added to message `.google.ads.admanager.v1.Application` 
+* A new message `ApplicationApprovalStatusEnum` is added 
+* A new message `ApplicationPlatformEnum` is added 
+* A new message `ApplicationStoreEnum` is added 
+* A new message `BatchArchiveApplicationsRequest` is added 
+* A new message `BatchArchiveApplicationsResponse` is added 
+* A new message `BatchCreateApplicationsRequest` is added 
+* A new message `BatchCreateApplicationsResponse` is added 
+* A new message `BatchUnarchiveApplicationsRequest` is added 
+* A new message `BatchUnarchiveApplicationsResponse` is added 
+* A new message `BatchUpdateApplicationsRequest` is added 
+* A new message `BatchUpdateApplicationsResponse` is added 
+* A new message `CreateApplicationRequest` is added 
+* A new message `UpdateApplicationRequest` is added 
+* A new message `WebviewClaimingStatusEnum` is added 
+* A new method `BatchArchiveApplications` is added to service `ApplicationService` 
+* A new method `BatchCreateApplications` is added to service `ApplicationService` 
+* A new method `BatchUnarchiveApplications` is added to service `ApplicationService` 
+* A new method `BatchUpdateApplications` is added to service `ApplicationService` 
+* A new method `CreateApplication` is added to service `ApplicationService` 
+* A new method `UpdateApplication` is added to service `ApplicationService` 
+* Add readonly OAuth scope 
+* added new API dimension: CREATIVE_SSL_SCAN_RESULT 
+* added new PUBLIC dimension: CREATIVE_SSL_COMPLIANCE_OVERRIDE_NAME 
+* added new PUBLIC dimension: CREATIVE_SSL_SCAN_RESULT_NAME 
+* added new PUBLIC dimension: LINE_ITEM_AVERAGE_NUMBER_OF_VIEWERS 
+* added new PUBLIC dimension: TARGETS_CUSTOMER_MATCHING_LIST 
+* added new PUBLIC metric: AD_SERVER_ACTIVE_VIEW_REVENUE 
+* Added child publisher resource. 
+* Add ProposalLineItem service and messages to the API. 
+* This is referenced for delegation_type in mcm_earnings 
+* Expose both `get` and `list` methods for RichMediaAdsCompanies to external clients. 
+* Added McmEarnings service 
+* New REQUIRED field `display_name` in message `.google.ads.admanager.v1.Label` 
+* New REQUIRED field `types` in message `.google.ads.admanager.v1.Label` 
+#### Bug Fixes
+
+* An existing value `DEMAND_SUBCHANNEL_ALL` is removed from enum `Dimension` 
+* Changed field behavior for an existing field `display_name` in message `.google.ads.admanager.v1.Application` 
+* Remove unused AdManagerError type 
+* Removed UNIFIED_PRICING_RULE_ID dimension 
+* Removed UNIFIED_PRICING_RULE_NAME dimension 
+#### Documentation
+
+* `UNIFIED_PRICING_RULE_ID` in enum `Dimension` is deprecated 
+* `UNIFIED_PRICING_RULE_NAME` in enum `Dimension` is deprecated 
+* A comment for enum value `DEMAND_SUBCHANNEL_NAME` in enum `Dimension` is changed 
+* A comment for enum value `DEMAND_SUBCHANNEL` in enum `Dimension` is changed 
+* A comment for enum value `PRICING_RULE_ID` in enum `Dimension` is changed 
+* A comment for enum value `PRICING_RULE_NAME` in enum `Dimension` is changed 
+* A comment for enum value `UNIFIED_PRICING_RULE_ID` in enum `Dimension` is changed 
+* A comment for enum value `UNIFIED_PRICING_RULE_NAME` in enum `Dimension` is changed 
+* A comment for field `display_name` in message `.google.ads.admanager.v1.Application` is changed 
+* A comment for field `filter` in message `.google.ads.admanager.v1.ListApplicationsRequest` is changed 
+* Clarify the behavior of the date_time_range filter when combined with a PENDING manual_review_status. 
+* Expand regex to regular expression 
+* Remove usage of and/or slashes 
+* Replace 'via' in all docs 
+* Replace all curly quotes with regular quotes 
+
 ### 3.2.0 (2026-04-02)
 
 #### Features
diff --git a/google-ads-ad_manager-v1/lib/google/ads/ad_manager/v1/version.rb b/google-ads-ad_manager-v1/lib/google/ads/ad_manager/v1/version.rb
index 3aa5e8d117b8..34db684cb599 100644
--- a/google-ads-ad_manager-v1/lib/google/ads/ad_manager/v1/version.rb
+++ b/google-ads-ad_manager-v1/lib/google/ads/ad_manager/v1/version.rb
@@ -21,7 +21,7 @@ module Google
   module Ads
     module AdManager
       module V1
-        VERSION = "3.2.0"
+        VERSION = "4.0.0"
       end
     end
   end
diff --git a/google-ads-ad_manager-v1/snippets/snippet_metadata_google.ads.admanager.v1.json b/google-ads-ad_manager-v1/snippets/snippet_metadata_google.ads.admanager.v1.json
index 2d185ef9d413..a5c2c336a2b2 100644
--- a/google-ads-ad_manager-v1/snippets/snippet_metadata_google.ads.admanager.v1.json
+++ b/google-ads-ad_manager-v1/snippets/snippet_metadata_google.ads.admanager.v1.json
@@ -1,7 +1,7 @@
 {
   "client_library": {
     "name": "google-ads-ad_manager-v1",
-    "version": "3.2.0",
+    "version": "4.0.0",
     "language": "RUBY",
     "apis": [
       {