diff --git a/.serena/memories/backend/auth-permissions-product-domains.md b/.serena/memories/backend/auth-permissions-product-domains.md
index 2a58e49dfd..fc9dc51bbf 100644
--- a/.serena/memories/backend/auth-permissions-product-domains.md
+++ b/.serena/memories/backend/auth-permissions-product-domains.md
@@ -21,7 +21,7 @@
 - Team role flags are normalized as owner > admin > editor > viewer. Owner/admin imply edit; any membership row implies read.
 - File/project role rows only count with a live team membership: the file/project permission queries require a matching `team_profile_rel` row, and leaving or removing a member deletes their team-scoped `file`/`project`/`team-project-profile-rel` rows (GHSA-v9r9-h77c-55m2).
 - File/project/comment checks are implemented in the owning command namespaces, often via helpers imported from `files`, `teams`, or `projects`; do not bypass those helpers with direct DB lookups unless preserving their not-found semantics.
-- Comment permission includes both logged-in state and the file/team comment policy. Shared viewer paths may pass `share-id`; preserve that path when changing comment queries.
+- Comment permission includes both logged-in state and the file/team comment policy. Shared viewer paths may pass `share-id`; preserve that path when changing comment queries. RPCs that accept `share-id` enforce the link's page scope before mutating (`share-link-pages` + `check-page-scope`): a thread or page outside the link raises `:not-found`, and that check runs before the ownership checks. `get-profiles-for-file-comments` filters its query by the same pages. `mark-all-threads-as-read` does not take `share-id`.
 
 ## Teams, projects, and invitations
 
diff --git a/backend/src/app/rpc/commands/comments.clj b/backend/src/app/rpc/commands/comments.clj
index 8ca0a165bc..6c83247998 100644
--- a/backend/src/app/rpc/commands/comments.clj
+++ b/backend/src/app/rpc/commands/comments.clj
@@ -41,6 +41,23 @@
 
 (def comment-max-length 750)
 
+(defn- share-link-pages
+  "The set of pages granted by a share-link, or nil when the access to the
+   file is not restricted to a page scope."
+  [perms]
+  (when (= :share-link (:type perms))
+    (or (:pages perms) #{})))
+
+(defn- check-page-scope
+  "Raises a :not-found error when `page-id` is outside the page scope granted
+   by a share-link."
+  [perms page-id]
+  (when-let [pages (share-link-pages perms)]
+    (when-not (contains? pages page-id)
+      (ex/raise :type :not-found
+                :code :object-not-found
+                :hint "not found"))))
+
 (defn- format-comment
   [{:keys [content]}]
   (->> (d/interleave-all
@@ -233,8 +250,8 @@
   (db/run! cfg (fn [{:keys [::db/conn] :as cfg}]
                  (let [perms (files/check-comment-permissions! cfg profile-id file-id share-id)
                        threads (get-comment-threads conn profile-id file-id)]
-                   (if (= :share-link (:type perms))
-                     (filterv #(contains? (:pages perms) (:page-id %)) threads)
+                   (if-let [pages (share-link-pages perms)]
+                     (filterv #(contains? pages (:page-id %)) threads)
                      threads)))))
 
 (defn- get-comment-threads-sql
@@ -335,11 +352,8 @@
                  (let [perms  (files/check-comment-permissions! cfg profile-id file-id share-id)
                        thread (some-> (db/exec-one! conn [sql:get-comment-thread profile-id file-id id])
                                       (decode-row))]
-                   (when (and thread (= :share-link (:type perms)))
-                     (when-not (contains? (:pages perms) (:page-id thread))
-                       (ex/raise :type :not-found
-                                 :code :object-not-found
-                                 :hint "not found")))
+                   (when thread
+                     (check-page-scope perms (:page-id thread)))
                    thread))))
 
 ;; --- COMMAND: Retrieve Comments
@@ -359,11 +373,7 @@
   (db/run! cfg (fn [{:keys [::db/conn] :as cfg}]
                  (let [{:keys [file-id page-id]} (get-comment-thread conn thread-id)
                        perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
-                   (when (and (= :share-link (:type perms))
-                              (not (contains? (:pages perms) page-id)))
-                     (ex/raise :type :not-found
-                               :code :object-not-found
-                               :hint "not found"))
+                   (check-page-scope perms page-id)
                    (get-comments conn thread-id)))))
 
 (def sql:get-comments
@@ -388,32 +398,49 @@
 ;; All the profiles that had comment the file, plus the current
 ;; profile.
 
+(defn- file-comment-users-sql
+  [where]
+  (str/ffmt
+   "WITH available_profiles AS (
+      SELECT DISTINCT c.owner_id AS id
+        FROM comment c
+        JOIN comment_thread ct
+          ON ct.id = c.thread_id
+       WHERE ct.file_id = ?::uuid
+         %1
+    ),
+    profile_ids AS (
+      SELECT id FROM available_profiles
+      UNION
+      SELECT ?::uuid
+    )
+    SELECT p.id,
+           p.email,
+           p.fullname AS name,
+           p.fullname,
+           p.photo_id,
+           p.is_active
+      FROM profile p
+      JOIN profile_ids AS x
+        ON x.id = p.id;"
+   where))
+
 (def ^:private sql:file-comment-users
-  "WITH available_profiles AS (
-     SELECT DISTINCT c.owner_id AS id
-     FROM comment c
-     JOIN comment_thread ct
-       ON ct.id = c.thread_id
-    WHERE ct.file_id = ?::uuid
-  ),
-  profile_ids AS (
-    SELECT id FROM available_profiles
-    UNION
-    SELECT ?::uuid
-  )
-  SELECT p.id,
-         p.email,
-         p.fullname AS name,
-         p.fullname,
-         p.photo_id,
-         p.is_active
-    FROM profile p
-    JOIN profile_ids AS x
-      ON x.id = p.id;")
+  (file-comment-users-sql ""))
+
+(def ^:private sql:file-comment-users-by-page
+  (file-comment-users-sql "AND ct.page_id = ANY(?::uuid[])"))
 
 (defn get-file-comments-users
-  [conn file-id profile-id]
-  (db/exec! conn [sql:file-comment-users file-id profile-id]))
+  "Returns the profiles of the users that commented the file. When `pages` is
+   not nil, only the commenters of the threads on those pages are returned."
+  [conn file-id profile-id pages]
+  (if (some? pages)
+    (db/exec! conn [sql:file-comment-users-by-page
+                    file-id
+                    (db/create-array conn "uuid" pages)
+                    profile-id])
+    (db/exec! conn [sql:file-comment-users file-id profile-id])))
 
 (def ^:private
   schema:get-profiles-for-file-comments
@@ -423,14 +450,17 @@
 
 (sv/defmethod ::get-profiles-for-file-comments
   "Retrieves a list of profiles with limited set of properties of all
-  participants on comment threads of the file."
+  participants on comment threads of the file. When the request is done with
+  a share link, only the participants on the pages granted by the link are
+  returned."
   {::doc/added "1.15"
-   ::doc/changes ["1.15" "Imported from queries and renamed."]
+   ::doc/changes ["1.15" "Imported from queries and renamed."
+                  "2.19" "With a share link, only the participants on the pages granted by the link are returned."]
    ::sm/params schema:get-profiles-for-file-comments}
   [cfg {:keys [::rpc/profile-id file-id share-id]}]
   (db/run! cfg (fn [{:keys [::db/conn] :as cfg}]
-                 (files/check-comment-permissions! cfg profile-id file-id share-id)
-                 (get-file-comments-users conn file-id profile-id))))
+                 (let [perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
+                   (get-file-comments-users conn file-id profile-id (share-link-pages perms))))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; MUTATION COMMANDS
@@ -472,21 +502,22 @@
    ::rtry/when rtry/conflict-exception?
    ::sm/params schema:create-comment-thread}
   [cfg {:keys [::rpc/profile-id file-id page-id share-id] :as params}]
-  (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
+    (check-page-scope perms page-id)
 
-  (let [{:keys [team-id project-id] :as file} (get-file cfg file-id page-id)]
-    (-> cfg
-        (assoc ::quotes/profile-id profile-id)
-        (assoc ::quotes/team-id team-id)
-        (assoc ::quotes/project-id project-id)
-        (assoc ::quotes/file-id file-id)
-        (quotes/check! {::quotes/id ::quotes/comment-threads-per-file}
-                       {::quotes/id ::quotes/comments-per-file}))
+    (let [{:keys [team-id project-id] :as file} (get-file cfg file-id page-id)]
+      (-> cfg
+          (assoc ::quotes/profile-id profile-id)
+          (assoc ::quotes/team-id team-id)
+          (assoc ::quotes/project-id project-id)
+          (assoc ::quotes/file-id file-id)
+          (quotes/check! {::quotes/id ::quotes/comment-threads-per-file}
+                         {::quotes/id ::quotes/comments-per-file}))
 
-    (let [params (assoc params ::file file)
-          thread (db/tx-run! cfg create-comment-thread params)]
+      (let [params (assoc params ::file file)
+            thread (db/tx-run! cfg create-comment-thread params)]
 
-      (vary-meta thread assoc ::audit/props (assoc thread :team-id team-id)))))
+        (vary-meta thread assoc ::audit/props (assoc thread :team-id team-id))))))
 
 (defn- create-comment-thread
   [{:keys [::db/conn] :as cfg}
@@ -557,8 +588,9 @@
    ::sm/params schema:update-comment-thread-status
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id id share-id]}]
-  (let [{:keys [file-id]} (get-comment-thread conn id ::sql/for-update true)]
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [thread (get-comment-thread conn id ::sql/for-update true)
+        perms  (files/check-comment-permissions! cfg profile-id (:file-id thread) share-id)]
+    (check-page-scope perms (:page-id thread))
     (upsert-comment-thread-status! conn profile-id id)))
 
 ;; --- COMMAND: Update Comment Thread
@@ -575,8 +607,9 @@
    ::sm/params schema:update-comment-thread
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id id is-resolved share-id]}]
-  (let [{:keys [file-id]} (get-comment-thread conn id ::sql/for-update true)]
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [thread (get-comment-thread conn id ::sql/for-update true)
+        perms  (files/check-comment-permissions! cfg profile-id (:file-id thread) share-id)]
+    (check-page-scope perms (:page-id thread))
     (db/update! conn :comment-thread
                 {:is-resolved is-resolved}
                 {:id id})
@@ -601,56 +634,58 @@
   (let [{:keys [file-id page-id] :as thread}
         (get-comment-thread conn thread-id ::sql/for-update true)
 
-        {:keys [team-id project-id] :as file}
-        (get-file cfg file-id page-id)]
+        perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
 
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+    (check-page-scope perms page-id)
 
-    (quotes/check! cfg {::quotes/id ::quotes/comments-per-file
-                        ::quotes/profile-id profile-id
-                        ::quotes/team-id team-id
-                        ::quotes/project-id project-id
-                        ::quotes/file-id file-id})
+    (let [{:keys [team-id project-id] :as file}
+          (get-file cfg file-id page-id)]
 
-    (let [profile  (profile/get-profile conn profile-id)
-          mentions (into #{} mentions)
-          params   {:id (uuid/next)
-                    :created-at request-at
-                    :modified-at request-at
-                    :thread-id thread-id
-                    :owner-id profile-id
-                    :content content
-                    :mentions (db/encode-pgarray mentions conn "uuid")}
+      (quotes/check! cfg {::quotes/id ::quotes/comments-per-file
+                          ::quotes/profile-id profile-id
+                          ::quotes/team-id team-id
+                          ::quotes/project-id project-id
+                          ::quotes/file-id file-id})
 
-          comment (-> (db/insert! conn :comment params)
-                      (decode-row)
-                      (assoc :file-id file-id)
-                      (add-owner profile))]
+      (let [profile  (profile/get-profile conn profile-id)
+            mentions (into #{} mentions)
+            params   {:id (uuid/next)
+                      :created-at request-at
+                      :modified-at request-at
+                      :thread-id thread-id
+                      :owner-id profile-id
+                      :content content
+                      :mentions (db/encode-pgarray mentions conn "uuid")}
 
-      ;; Update thread modified-at attribute and assoc the current
-      ;; profile to the participant set.
-      (let [mentions     (into (:mentions thread) mentions)
-            participants (-> (:participants thread #{})
-                             (conj profile-id))
-            params       {:modified-at request-at
-                          :participants (db/tjson participants)
-                          :mentions (db/encode-pgarray mentions conn "uuid")}
+            comment (-> (db/insert! conn :comment params)
+                        (decode-row)
+                        (assoc :file-id file-id)
+                        (add-owner profile))]
 
-            ;; Update the page-name cached attribute on comment thread table.
-            params       (cond-> params
-                           (not= (:page-name file) (:page-name thread))
-                           (assoc :page-name (:page-name file)))]
+        ;; Update thread modified-at attribute and assoc the current
+        ;; profile to the participant set.
+        (let [mentions     (into (:mentions thread) mentions)
+              participants (-> (:participants thread #{})
+                               (conj profile-id))
+              params       {:modified-at request-at
+                            :participants (db/tjson participants)
+                            :mentions (db/encode-pgarray mentions conn "uuid")}
 
-        (db/update! conn :comment-thread params
-                    {:id thread-id}
-                    {::db/return-keys false}))
+              ;; Update the page-name cached attribute on comment thread table.
+              params       (cond-> params
+                             (not= (:page-name file) (:page-name thread))
+                             (assoc :page-name (:page-name file)))]
 
-      ;; Update the current profile status in relation to the current thread
-      (upsert-comment-thread-status! conn profile-id thread-id)
+          (db/update! conn :comment-thread params
+                      {:id thread-id}
+                      {::db/return-keys false}))
 
-      (send-comment-emails! conn profile comment thread file)
+        ;; Update the current profile status in relation to the current thread
+        (upsert-comment-thread-status! conn profile-id thread-id)
 
-      (vary-meta comment assoc ::audit/props (assoc comment :team-id team-id)))))
+        (send-comment-emails! conn profile comment thread file)
+
+        (vary-meta comment assoc ::audit/props (assoc comment :team-id team-id))))))
 
 ;; --- COMMAND: Update Comment
 
@@ -673,9 +708,11 @@
         (get-comment conn id ::sql/for-update true)
 
         {:keys [file-id page-id] :as thread}
-        (get-comment-thread conn thread-id ::sql/for-update true)]
+        (get-comment-thread conn thread-id ::sql/for-update true)
 
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+        perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
+
+    (check-page-scope perms page-id)
 
     ;; Don't allow edit comments to not owners
     (when-not (= owner-id profile-id)
@@ -713,8 +750,13 @@
    ::sm/params schema:delete-comment-thread
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id id share-id]}]
-  (let [{:keys [owner-id file-id] :as thread} (get-comment-thread conn id ::sql/for-update true)]
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [{:keys [owner-id file-id page-id] :as thread}
+        (get-comment-thread conn id ::sql/for-update true)
+
+        perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
+
+    (check-page-scope perms page-id)
+
     (when-not (= owner-id profile-id)
       (ex/raise :type :validation
                 :code :not-allowed))
@@ -739,10 +781,12 @@
   (let [{:keys [owner-id thread-id] :as comment}
         (get-comment conn id ::sql/for-update true)
 
-        {:keys [file-id]}
-        (get-comment-thread conn thread-id)]
+        {:keys [file-id page-id]}
+        (get-comment-thread conn thread-id)
 
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+        perms (files/check-comment-permissions! cfg profile-id file-id share-id)]
+
+    (check-page-scope perms page-id)
     (when-not (= owner-id profile-id)
       (ex/raise :type :validation
                 :code :not-allowed))
@@ -766,8 +810,9 @@
    ::sm/params schema:update-comment-thread-position
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id ::rpc/request-at id position frame-id share-id]}]
-  (let [{:keys [file-id]} (get-comment-thread conn id ::sql/for-update true)]
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [thread (get-comment-thread conn id ::sql/for-update true)
+        perms  (files/check-comment-permissions! cfg profile-id (:file-id thread) share-id)]
+    (check-page-scope perms (:page-id thread))
     (db/update! conn :comment-thread
                 {:modified-at request-at
                  :position (db/pgpoint position)
@@ -790,8 +835,9 @@
    ::sm/params schema:update-comment-thread-frame
    ::db/transaction true}
   [{:keys [::db/conn] :as cfg} {:keys [::rpc/profile-id ::rpc/request-at id frame-id share-id]}]
-  (let [{:keys [file-id]} (get-comment-thread conn id ::sql/for-update true)]
-    (files/check-comment-permissions! cfg profile-id file-id share-id)
+  (let [thread (get-comment-thread conn id ::sql/for-update true)
+        perms  (files/check-comment-permissions! cfg profile-id (:file-id thread) share-id)]
+    (check-page-scope perms (:page-id thread))
     (db/update! conn :comment-thread
                 {:modified-at request-at
                  :frame-id frame-id}
diff --git a/backend/test/backend_tests/rpc_comment_test.clj b/backend/test/backend_tests/rpc_comment_test.clj
index 0c58687751..0d8f6b77e5 100644
--- a/backend/test/backend_tests/rpc_comment_test.clj
+++ b/backend/test/backend_tests/rpc_comment_test.clj
@@ -323,6 +323,14 @@
                               :frame-id uuid/zero
                               :share-id share-id})]
         (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "outsider with who-comment=team share-link cannot get-profiles-for-file-comments"
+      (let [out (th/command! {::th/type :get-profiles-for-file-comments
+                              ::rpc/profile-id (:id outsider)
+                              :file-id (:id file)
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
         (t/is (= :not-found (th/ex-type (:error out))))))))
 
 (t/deftest share-link-who-comment-all-can-comment
@@ -449,6 +457,292 @@
         (t/is (not (th/success? out)))
         (t/is (= :not-found (th/ex-type (:error out))))))))
 
+(t/deftest share-link-page-scope-enforced-for-comment-profiles
+  (let [owner    (th/create-profile* 1 {:is-active true})
+        outsider (th/create-profile* 2 {:is-active true})
+        member   (th/create-profile* 3 {:is-active true})
+
+        team     (th/create-team* 1 {:profile-id (:id owner)})
+        _        (th/create-team-role* {:team-id (:id team)
+                                        :profile-id (:id member)
+                                        :role :editor})
+        project  (th/create-project* 1 {:team-id (:id team)
+                                        :profile-id (:id owner)})
+        file     (th/create-file* 1 {:profile-id (:id owner)
+                                     :project-id (:id project)})
+
+        page-a   (get-in file [:data :pages 0])
+        page-b   (uuid/random)
+
+        _        (th/command! {::th/type :update-file
+                               ::rpc/profile-id (:id owner)
+                               :id (:id file)
+                               :session-id (uuid/random)
+                               :revn 0
+                               :vern 0
+                               :changes [{:type :add-page
+                                          :id page-b
+                                          :page {:id page-b
+                                                 :name "Page B"
+                                                 :options {}
+                                                 :objects {}}}]})
+
+        thread-a (th/command! {::th/type :create-comment-thread
+                               ::rpc/profile-id (:id owner)
+                               :file-id (:id file)
+                               :page-id page-a
+                               :position (gpt/point 0)
+                               :content "comment on page A"
+                               :frame-id uuid/zero})
+
+        thread-b (th/command! {::th/type :create-comment-thread
+                               ::rpc/profile-id (:id member)
+                               :file-id (:id file)
+                               :page-id page-b
+                               :position (gpt/point 0)
+                               :content "comment on page B"
+                               :frame-id uuid/zero})
+
+        thread-a-id (get-in thread-a [:result :id])
+        thread-b-id (get-in thread-b [:result :id])
+        thread-b-comment-id (get-in thread-b [:result :comment-id])
+
+        share    (th/command! {::th/type :create-share-link
+                               ::rpc/profile-id (:id owner)
+                               :file-id (:id file)
+                               :pages #{page-a}
+                               :who-comment "all"
+                               :who-inspect "all"})
+        share-id (get-in share [:result :id])
+
+        ;; A link without pages grants access to nothing.
+        empty-share    (th/command! {::th/type :create-share-link
+                                     ::rpc/profile-id (:id owner)
+                                     :file-id (:id file)
+                                     :pages #{}
+                                     :who-comment "all"
+                                     :who-inspect "all"})
+        empty-share-id (get-in empty-share [:result :id])]
+
+    (t/testing "the comment threads are created"
+      (t/is (th/success? thread-a))
+      (t/is (th/success? thread-b)))
+
+    (t/testing "share-link holder only gets the profiles of the shared page commenters"
+      (let [out    (th/command! {::th/type :get-profiles-for-file-comments
+                                 ::rpc/profile-id (:id outsider)
+                                 :file-id (:id file)
+                                 :share-id share-id})
+            emails (set (map :email (:result out)))]
+        (t/is (th/success? out))
+        (t/is (contains? emails (:email owner)))
+        (t/is (contains? emails (:email outsider)))
+        (t/is (not (contains? emails (:email member))))))
+
+    (t/testing "share-link holder cannot update the status of a thread of an unshared page"
+      (let [out (th/command! {::th/type :update-comment-thread-status
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-id
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot update a comment of an unshared page"
+      (let [out (th/command! {::th/type :update-comment
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-comment-id
+                              :content "outsider edit on page B"
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot delete a comment of an unshared page"
+      (let [out (th/command! {::th/type :delete-comment
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-comment-id
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot delete a thread of an unshared page"
+      (let [out (th/command! {::th/type :delete-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-id
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot create a thread on an unshared page"
+      (let [out (th/command! {::th/type :create-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :file-id (:id file)
+                              :page-id page-b
+                              :position (gpt/point 0)
+                              :content "comment on page B"
+                              :frame-id uuid/zero
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot move a thread of an unshared page"
+      (let [out (th/command! {::th/type :update-comment-thread-position
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-id
+                              :position (gpt/point 10 10)
+                              :frame-id uuid/zero
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder cannot resize a thread of an unshared page"
+      (let [out (th/command! {::th/type :update-comment-thread-frame
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-id
+                              :frame-id uuid/zero
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder can move a thread of the shared page"
+      (let [out (th/command! {::th/type :update-comment-thread-position
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-a-id
+                              :position (gpt/point 10 10)
+                              :frame-id uuid/zero
+                              :share-id share-id})]
+        (t/is (th/success? out))))
+
+    (t/testing "share-link holder can resize a thread of the shared page"
+      (let [out (th/command! {::th/type :update-comment-thread-frame
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-a-id
+                              :frame-id uuid/zero
+                              :share-id share-id})]
+        (t/is (th/success? out))))
+
+    (t/testing "share-link holder cannot reply to a thread of an unshared page"
+      (let [out (th/command! {::th/type :create-comment
+                              ::rpc/profile-id (:id outsider)
+                              :thread-id thread-b-id
+                              :content "outsider reply on page B"
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder can reply to a thread of the shared page"
+      (let [out (th/command! {::th/type :create-comment
+                              ::rpc/profile-id (:id outsider)
+                              :thread-id thread-a-id
+                              :content "outsider reply on page A"
+                              :share-id share-id})]
+        (t/is (th/success? out))))
+
+    (t/testing "share-link holder cannot resolve a thread of an unshared page"
+      (let [out (th/command! {::th/type :update-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-b-id
+                              :is-resolved true
+                              :share-id share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link holder can resolve a thread of the shared page"
+      (let [out (th/command! {::th/type :update-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :id thread-a-id
+                              :is-resolved true
+                              :share-id share-id})]
+        (t/is (th/success? out))))
+
+    (t/testing "share-link holder can write on the shared page"
+      (let [thread (th/command! {::th/type :create-comment-thread
+                                 ::rpc/profile-id (:id outsider)
+                                 :file-id (:id file)
+                                 :page-id page-a
+                                 :position (gpt/point 0)
+                                 :content "outsider comment on page A"
+                                 :frame-id uuid/zero
+                                 :share-id share-id})
+            thread-id  (get-in thread [:result :id])
+            comment-id (get-in thread [:result :comment-id])]
+
+        (t/is (th/success? thread))
+
+        (t/testing "can mark a thread as read"
+          (let [out (th/command! {::th/type :update-comment-thread-status
+                                  ::rpc/profile-id (:id outsider)
+                                  :id thread-id
+                                  :share-id share-id})]
+            (t/is (th/success? out))))
+
+        (t/testing "can edit its comment"
+          (let [out (th/command! {::th/type :update-comment
+                                  ::rpc/profile-id (:id outsider)
+                                  :id comment-id
+                                  :content "outsider edit on page A"
+                                  :share-id share-id})]
+            (t/is (th/success? out))))
+
+        (t/testing "can delete its comment"
+          (let [out (th/command! {::th/type :delete-comment
+                                  ::rpc/profile-id (:id outsider)
+                                  :id comment-id
+                                  :share-id share-id})]
+            (t/is (th/success? out))))
+
+        (t/testing "can delete its thread"
+          (let [out (th/command! {::th/type :delete-comment-thread
+                                  ::rpc/profile-id (:id outsider)
+                                  :id thread-id
+                                  :share-id share-id})]
+            (t/is (th/success? out))))))
+
+    (t/testing "share-link without pages does not leak the commenter profiles"
+      (let [out    (th/command! {::th/type :get-profiles-for-file-comments
+                                 ::rpc/profile-id (:id outsider)
+                                 :file-id (:id file)
+                                 :share-id empty-share-id})
+            emails (set (map :email (:result out)))]
+        (t/is (th/success? out))
+        (t/is (= #{(:email outsider)} emails))))
+
+    (t/testing "share-link without pages cannot create a thread"
+      (let [out (th/command! {::th/type :create-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :file-id (:id file)
+                              :page-id page-a
+                              :position (gpt/point 0)
+                              :content "outsider comment on page A"
+                              :frame-id uuid/zero
+                              :share-id empty-share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link without pages lists no comment threads"
+      (let [out (th/command! {::th/type :get-comment-threads
+                              ::rpc/profile-id (:id outsider)
+                              :file-id (:id file)
+                              :share-id empty-share-id})]
+        (t/is (th/success? out))
+        (t/is (= [] (:result out)))))
+
+    (t/testing "share-link without pages cannot get a comment thread"
+      (let [out (th/command! {::th/type :get-comment-thread
+                              ::rpc/profile-id (:id outsider)
+                              :file-id (:id file)
+                              :id thread-a-id
+                              :share-id empty-share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))
+
+    (t/testing "share-link without pages cannot get the comments of a thread"
+      (let [out (th/command! {::th/type :get-comments
+                              ::rpc/profile-id (:id outsider)
+                              :thread-id thread-a-id
+                              :share-id empty-share-id})]
+        (t/is (not (th/success? out)))
+        (t/is (= :not-found (th/ex-type (:error out))))))))
+
 (t/deftest membership-can-still-comment
   (let [owner   (th/create-profile* 1 {:is-active true})
         member  (th/create-profile* 2 {:is-active true})
@@ -461,7 +755,23 @@
                                        :profile-id (:id owner)})
         file    (th/create-file* 1 {:profile-id (:id owner)
                                     :project-id (:id project)})
-        page-id (get-in file [:data :pages 0])]
+        page-id (get-in file [:data :pages 0])
+
+        _       (th/command! {::th/type :create-comment-thread
+                              ::rpc/profile-id (:id owner)
+                              :file-id (:id file)
+                              :page-id page-id
+                              :position (gpt/point 0)
+                              :content "owner comment"
+                              :frame-id uuid/zero})
+
+        thread  (th/command! {::th/type :create-comment-thread
+                              ::rpc/profile-id (:id member)
+                              :file-id (:id file)
+                              :page-id page-id
+                              :position (gpt/point 0)
+                              :content "member comment"
+                              :frame-id uuid/zero})]
 
     (t/testing "team member can get-comment-threads without share-id"
       (let [out (th/command! {::th/type :get-comment-threads
@@ -470,14 +780,45 @@
         (t/is (th/success? out))))
 
     (t/testing "team member can create-comment-thread without share-id"
-      (let [out (th/command! {::th/type :create-comment-thread
+      (t/is (th/success? thread)))
+
+    (t/testing "team member can move a thread of the file"
+      (let [out (th/command! {::th/type :update-comment-thread-position
                               ::rpc/profile-id (:id member)
-                              :file-id (:id file)
-                              :page-id page-id
-                              :position (gpt/point 0)
-                              :content "member comment"
+                              :id (get-in thread [:result :id])
+                              :position (gpt/point 10 10)
                               :frame-id uuid/zero})]
-        (t/is (th/success? out))))))
+        (t/is (th/success? out))))
+
+    (t/testing "team member can resize a thread of the file"
+      (let [out (th/command! {::th/type :update-comment-thread-frame
+                              ::rpc/profile-id (:id member)
+                              :id (get-in thread [:result :id])
+                              :frame-id uuid/zero})]
+        (t/is (th/success? out))))
+
+    (t/testing "team member can reply to a thread of the file"
+      (let [out (th/command! {::th/type :create-comment
+                              ::rpc/profile-id (:id member)
+                              :thread-id (get-in thread [:result :id])
+                              :content "member reply"})]
+        (t/is (th/success? out))))
+
+    (t/testing "team member can resolve a thread of the file"
+      (let [out (th/command! {::th/type :update-comment-thread
+                              ::rpc/profile-id (:id member)
+                              :id (get-in thread [:result :id])
+                              :is-resolved true})]
+        (t/is (th/success? out))))
+
+    (t/testing "team member gets the profiles of all the file commenters"
+      (let [out    (th/command! {::th/type :get-profiles-for-file-comments
+                                 ::rpc/profile-id (:id member)
+                                 :file-id (:id file)})
+            emails (set (map :email (:result out)))]
+        (t/is (th/success? out))
+        (t/is (contains? emails (:email member)))
+        (t/is (contains? emails (:email owner)))))))
 
 (t/deftest comment-audit-events-carry-team-id
   ;; Comment events carry the file id, so the resolver could find the team; the