/common/segments.proto 

--- v24/common/segments.proto   2026-07-21 22:02:13.000000000 +0000
+++ v25/common/segments.proto   2026-07-21 22:02:31.000000000 +0000
@@ -98,12 +99,17 @@
       191;

   // Ad network type.
-  google.ads.googleads.v24.enums.AdNetworkTypeEnum.AdNetworkType
+  google.ads.googleads.v25.enums.AdNetworkTypeEnum.AdNetworkType
       ad_network_type = 3;

   // Resource name of the ad group.
   optional string ad_group = 158;

+  // Ad sub format type. Segments YouTube non-skippable instream ads by
+  // duration. Has to always be selected together with ad_format_type.
+  google.ads.googleads.v25.enums.AdSubFormatTypeEnum.AdSubFormatType
+      ad_sub_format_type = 232;
+
   // Ad sub network type. Currently only available for ads running as part of
   // DemandGen campaigns on YouTube and has to always be selected together with
   // ad_network_type.