diff --git a/tools/migrations/20261001000000_ce_sp_zotero_linked_file_data_keys.mjs b/tools/migrations/20261001000000_ce_sp_zotero_linked_file_data_keys.mjs
new file mode 100644
index 0000000000..8dfef31a71
--- /dev/null
+++ b/tools/migrations/20261001000000_ce_sp_zotero_linked_file_data_keys.mjs
@@ -0,0 +1,77 @@
+import { batchedUpdate } from '@overleaf/mongo-utils/batchedUpdate.js'
+import { promiseMapWithLimit } from '@overleaf/promise-utils'
+import { db } from './lib/mongodb.mjs'
+
+const tags = ['server-ce', 'server-pro']
+
+const WRITE_CONCURRENCY = parseInt(process.env.WRITE_CONCURRENCY, 10) || 10
+
+// The Zotero module used to store linkedFileData with its own key names.
+// "Zotero: fix for 6.3.0" switched to the names accepted by the
+// overleaf-editor-core schema, but files imported before that still carry the
+// old keys, which document-updater rejects (e.g. when cloning the project).
+const LEGACY_KEYS = [
+  'zoteroGroupId',
+  'importedByUserId',
+  'importedByName',
+  'bibFormat',
+]
+
+function hasLegacyKeys(data) {
+  return (
+    data?.provider === 'zotero' && LEGACY_KEYS.some(key => key in data)
+  )
+}
+
+function convert(data) {
+  const importerId = data.importer_id ?? data.importedByUserId
+  const format = data.format ?? data.bibFormat
+  return {
+    provider: 'zotero',
+    group_id: data.group_id ?? data.zoteroGroupId ?? null,
+    ...(data.importedAt && { importedAt: data.importedAt }),
+    ...(importerId && { importer_id: importerId.toString() }),
+    importer_name: data.importer_name ?? data.importedByName ?? 'Unknown',
+    format: format === 'biblatex' ? 'biblatex' : 'bibtex',
+  }
+}
+
+function collectUpdates(folder, mongoPath, updates) {
+  if (!folder) return
+  ;(folder.fileRefs || []).forEach((file, i) => {
+    if (hasLegacyKeys(file?.linkedFileData)) {
+      updates[`${mongoPath}.fileRefs.${i}.linkedFileData`] = convert(
+        file.linkedFileData
+      )
+    }
+  })
+  ;(folder.folders || []).forEach((subfolder, i) => {
+    collectUpdates(subfolder, `${mongoPath}.folders.${i}`, updates)
+  })
+}
+
+const migrate = async () => {
+  await batchedUpdate(
+    db.projects,
+    {},
+    async nextBatch => {
+      await promiseMapWithLimit(WRITE_CONCURRENCY, nextBatch, async project => {
+        const updates = {}
+        ;(project.rootFolder || []).forEach((folder, i) => {
+          collectUpdates(folder, `rootFolder.${i}`, updates)
+        })
+        if (Object.keys(updates).length === 0) return
+        await db.projects.updateOne({ _id: project._id }, { $set: updates })
+      })
+    },
+    { _id: 1, rootFolder: 1 }
+  )
+}
+
+const rollback = async () => {}
+
+export default {
+  tags,
+  migrate,
+  rollback,
+}