diff --git a/src/activitypub/notes.js b/src/activitypub/notes.js
index ab1344218b..650b8c5cb2 100644
--- a/src/activitypub/notes.js
+++ b/src/activitypub/notes.js
@@ -267,7 +267,7 @@ Notes.assert = async (uid, input, options = { skipChecks: false }) => {
 
 		if (!hasTid && options.cid) {
 			// New topic, have category announce it
-			activitypub.out.announce.category(tid);
+			activitypub.out.announce.topic(tid);
 		}
 
 		return { tid, count };
diff --git a/src/activitypub/out.js b/src/activitypub/out.js
index 9c9bdb5dba..a0f553dab9 100644
--- a/src/activitypub/out.js
+++ b/src/activitypub/out.js
@@ -279,7 +279,7 @@ Out.like.note = enabledCheck(async (uid, pid) => {
 
 Out.announce = {};
 
-Out.announce.category = enabledCheck(async (tid) => {
+Out.announce.topic = enabledCheck(async (tid) => {
 	const { mainPid: pid, cid } = await topics.getTopicFields(tid, ['mainPid', 'cid']);
 
 	// Only local categories can announce
diff --git a/src/api/topics.js b/src/api/topics.js
index d7f2f4836f..8f769e4b32 100644
--- a/src/api/topics.js
+++ b/src/api/topics.js
@@ -323,11 +323,12 @@ topicsAPI.move = async (caller, { tid, cid }) => {
 				socketHelpers.sendNotificationToTopicOwner(tid, caller.uid, 'move', 'notifications:moved-your-topic');
 
 				if (utils.isNumber(cid) && parseInt(cid, 10) === -1) {
-					activitypub.out.remove.context(caller.uid, tid);
-					// tbd: activitypubApi.undo.announce?
+					activitypub.out.remove.context(caller.uid, tid); // 7888-style
+					activitypub.out.delete.note(caller.uid, topicData.mainPid); // threadiverse
+					// tbd: activitypubApi.undo.announce? // microblogs
 				} else {
 					activitypub.out.move.context(caller.uid, tid);
-					activitypub.out.announce.category(tid);
+					activitypub.out.announce.topic(tid);
 				}
 			}