diff --git a/api/server/routes/__tests__/share.spec.js b/api/server/routes/__tests__/share.spec.js
index 10d5ddaeba..3c8b976d36 100644
--- a/api/server/routes/__tests__/share.spec.js
+++ b/api/server/routes/__tests__/share.spec.js
@@ -374,7 +374,7 @@ describe('share routes', () => {
     );
   });
 
-  it('does not convert the source conversation when the share is not created', async () => {
+  it('converts the source conversation before creating the share so retries stay covered', async () => {
     mockGetSharedLinkExpiration.mockResolvedValue(activeExpiration);
     createSharedLink.mockResolvedValue(null);
 
@@ -383,7 +383,19 @@ describe('share routes', () => {
       .send({ targetMessageId: 'msg-123' });
 
     expect(response.status).toBe(404);
-    expect(applyForcedRetention).not.toHaveBeenCalled();
+    /**
+     * Retention runs before createSharedLink: a share attempt that fails (or hits an existing
+     * active share on retry) must still convert the touched conversation, otherwise a live
+     * share could outlast a source chat that never converts.
+     */
+    expect(applyForcedRetention).toHaveBeenCalledWith(
+      { userId: 'user-123', interfaceConfig: { retentionMode: RetentionMode.EPHEMERAL } },
+      { conversationId: 'convo-123' },
+      expect.objectContaining({ context: expect.any(String) }),
+    );
+    expect(applyForcedRetention.mock.invocationCallOrder[0]).toBeLessThan(
+      createSharedLink.mock.invocationCallOrder[0],
+    );
   });
 
   it('converts the source conversation under forced retention when updating a share', async () => {
diff --git a/api/server/routes/share.js b/api/server/routes/share.js
index c023988189..5177d1cad2 100644
--- a/api/server/routes/share.js
+++ b/api/server/routes/share.js
@@ -467,6 +467,18 @@ router.post(
   async (req, res) => {
     try {
       const { targetMessageId } = req.body;
+      /**
+       * Convert the source conversation before creating the link. createSharedLink rejects
+       * when an active share already exists, so a retention failure after creation would
+       * leave a live share whose source chat never converts — no retry could reach the
+       * cascade again. Converting first also lets the share expiration below read the
+       * converted conversation's deadline.
+       */
+      await enforceForcedRetention(
+        req,
+        req.params.conversationId,
+        'POST /api/share/:conversationId',
+      );
       const expiredAt = await resolveSharedLinkExpiration(req, req.params.conversationId);
       if (expiredAt != null && !isActiveExpirationDate(expiredAt)) {
         return res.status(404).end();
@@ -488,11 +500,6 @@ router.post(
       );
       if (created) {
         await grantCreationPermissions(created._id, req.user.id, grantPublic, expiredAt);
-        await enforceForcedRetention(
-          req,
-          req.params.conversationId,
-          'POST /api/share/:conversationId',
-        );
         res.status(200).json(created);
       } else {
         res.status(404).end();