diff --git a/src/lib/api/feed-manip.ts b/src/lib/api/feed-manip.ts
index c2b80ca042..6e78283ea0 100644
--- a/src/lib/api/feed-manip.ts
+++ b/src/lib/api/feed-manip.ts
@@ -41,6 +41,8 @@ export class FeedViewPostsSlice {
   isFallbackMarker: boolean
   isOrphan: boolean
   rootUri: string
+  participantDids: Set<string> = new Set()
+  additionalParticipantProfiles: AppBskyActorDefs.ProfileViewBasic[] = []
 
   constructor(feedPost: FeedViewPost) {
     const {post, reply, reason} = feedPost
@@ -211,12 +213,19 @@ export class FeedViewPostsSlice {
       rootAuthor,
     }
   }
+
+  getAuthorDids(): string[] {
+    return Object.values(this.getAuthors())
+      .map(p => (p ? p.did : undefined))
+      .filter(Boolean) as string[]
+  }
 }
 
 export class FeedTuner {
   seenKeys: Set<string> = new Set()
   seenUris: Set<string> = new Set()
-  seenRootUris: Set<string> = new Set()
+  seenRootUris: Map<string, {participantDids: Set<string>}> = new Map()
+  profileMap: Map<string, AppBskyActorDefs.ProfileViewBasic> = new Map()
 
   constructor(public tunerFns: FeedTunerFn[]) {}
 
@@ -345,13 +354,36 @@ export class FeedTuner {
     dryRun: boolean,
   ): FeedViewPostsSlice[] {
     for (let i = 0; i < slices.length; i++) {
-      const rootUri = slices[i].rootUri
-      if (!slices[i].isRepost && tuner.seenRootUris.has(rootUri)) {
+      const slice = slices[i]
+      const rootUri = slice.rootUri
+      const authorsDids = slice.getAuthorDids()
+      if (!slice.isRepost && tuner.seenRootUris.has(rootUri)) {
+        const seen = tuner.seenRootUris.get(rootUri)!
+        for (const did of authorsDids) {
+          seen.participantDids.add(did)
+        }
         slices.splice(i, 1)
         i--
       } else {
         if (!dryRun) {
-          tuner.seenRootUris.add(rootUri)
+          const participantDids = new Set(authorsDids)
+          slice.participantDids = participantDids
+          tuner.seenRootUris.set(rootUri, {participantDids})
+        }
+      }
+      for (const profile of Object.values(slice.getAuthors())) {
+        if (profile) {
+          tuner.profileMap.set(profile.did, profile)
+        }
+      }
+    }
+    for (const slice of slices) {
+      const visibleAuthors = new Set(slice.getAuthorDids())
+      for (const userDid of slice.participantDids) {
+        if (visibleAuthors.has(userDid)) continue
+        const profile = tuner.profileMap.get(userDid)
+        if (profile) {
+          slice.additionalParticipantProfiles.push(profile)
         }
       }
     }
diff --git a/src/state/queries/post-feed.ts b/src/state/queries/post-feed.ts
index ee3e2c14d2..b31c18583a 100644
--- a/src/state/queries/post-feed.ts
+++ b/src/state/queries/post-feed.ts
@@ -94,6 +94,7 @@ export interface FeedPostSlice {
     | AppBskyFeedDefs.ReasonRepost
     | ReasonFeedSource
     | {[k: string]: unknown; $type: string}
+  additionalParticipantProfiles?: AppBskyActorDefs.ProfileViewBasic[]
 }
 
 export interface FeedPageUnselected {
@@ -318,6 +319,8 @@ export function usePostFeedQuery(
                     isFallbackMarker: slice.isFallbackMarker,
                     feedContext: slice.feedContext,
                     reason: slice.reason,
+                    additionalParticipantProfiles:
+                      slice.additionalParticipantProfiles,
                     items: slice.items.map((item, i) => {
                       const feedPostSliceItem: FeedPostSliceItem = {
                         _reactKey: `${slice._reactKey}-${i}-${item.post.uri}`,
diff --git a/src/view/com/posts/FeedItem.tsx b/src/view/com/posts/FeedItem.tsx
index e90e8b885c..3359d7c637 100644
--- a/src/view/com/posts/FeedItem.tsx
+++ b/src/view/com/posts/FeedItem.tsx
@@ -84,9 +84,11 @@ export function FeedItem({
   isParentBlocked,
   isParentNotFound,
   rootPost,
+  additionalParticipantProfiles,
 }: FeedItemProps & {
   post: AppBskyFeedDefs.PostView
   rootPost: AppBskyFeedDefs.PostView
+  additionalParticipantProfiles?: AppBskyActorDefs.ProfileViewBasic[]
 }): React.ReactNode {
   const postShadowed = usePostShadow(post)
   const richText = useMemo(
@@ -120,6 +122,7 @@ export function FeedItem({
         isParentBlocked={isParentBlocked}
         isParentNotFound={isParentNotFound}
         rootPost={rootPost}
+        additionalParticipantProfiles={additionalParticipantProfiles}
       />
     )
   }
@@ -142,10 +145,12 @@ let FeedItemInner = ({
   isParentBlocked,
   isParentNotFound,
   rootPost,
+  additionalParticipantProfiles,
 }: FeedItemProps & {
   richText: RichTextAPI
   post: Shadow<AppBskyFeedDefs.PostView>
   rootPost: AppBskyFeedDefs.PostView
+  additionalParticipantProfiles?: AppBskyActorDefs.ProfileViewBasic[]
 }): React.ReactNode => {
   const queryClient = useQueryClient()
   const {openComposer} = useComposerControls()
@@ -392,6 +397,16 @@ let FeedItemInner = ({
             feedContext={feedContext}
             threadgateRecord={threadgateRecord}
           />
+
+          {additionalParticipantProfiles?.length && (
+            <View>
+              <Text>
+                {additionalParticipantProfiles
+                  .map(p => p.displayName)
+                  .join(', ')}
+              </Text>
+            </View>
+          )}
         </View>
       </View>
     </Link>
diff --git a/src/view/com/posts/FeedSlice.tsx b/src/view/com/posts/FeedSlice.tsx
index 0920026f60..c9e0d0558e 100644
--- a/src/view/com/posts/FeedSlice.tsx
+++ b/src/view/com/posts/FeedSlice.tsx
@@ -38,6 +38,7 @@ let FeedSlice = ({
           isParentBlocked={slice.items[0].isParentBlocked}
           isParentNotFound={slice.items[0].isParentNotFound}
           rootPost={slice.items[0].post}
+          additionalParticipantProfiles={slice.additionalParticipantProfiles}
         />
         <ViewFullThread uri={slice.items[0].uri} />
         <FeedItem
@@ -99,6 +100,9 @@ let FeedSlice = ({
           isParentNotFound={slice.items[i].isParentNotFound}
           hideTopBorder={hideTopBorder && i === 0}
           rootPost={slice.items[0].post}
+          additionalParticipantProfiles={
+            i === 0 ? slice.additionalParticipantProfiles : undefined
+          }
         />
       ))}
     </>