/resources/data_link.proto

--- v23/resources/data_link.proto   2026-06-18 21:38:48.000000000 +0000
+++ v24/resources/data_link.proto   2026-06-18 21:38:55.000000000 +0000
@@ -72,6 +72,13 @@
     YoutubeVideoIdentifier youtube_video = 6
         [(google.api.field_behavior) = IMMUTABLE];
   }
+
+  // Metadata for the data link.
+  oneof data_link_metadata {
+    // Immutable. Metadata for a YouTube link.
+    YoutubeLinkMetadata youtube_link_metadata = 7
+        [(google.api.field_behavior) = IMMUTABLE];
+  }
 }

 // The identifier for YouTube video
@@ -86,3 +93,12 @@
   // "https://www.youtube.com/watch?v=jV1vkHv4zq8&t=2s".
   optional string video_id = 2 [(google.api.field_behavior) = IMMUTABLE];
 }
+
+// Metadata specific to YouTube links.
+message YoutubeLinkMetadata {
+  // Immutable. The ID of a YouTube brand channel to help creators understand
+  // your brand. The channel must be linked to this account. This is a string
+  // value with “UC” prefix. For example, "UCK8sQmJBp8GCxrOtXWBpyEA".
+  optional string brand_channel_id = 1
+      [(google.api.field_behavior) = IMMUTABLE];
+}