diff --git a/routers/exam/templates.py b/routers/exam/templates.py
index 4ea2f58..adaa931 100644
--- a/routers/exam/templates.py
+++ b/routers/exam/templates.py
@@ -167,8 +167,12 @@ async def _upload_template_source_file(
 
     file_id = str(uuid.uuid4())
     safe_name = os.path.basename(upload.filename or "template.pdf")
-    bucket = f"cc.institutes.{institute_id}.private" if institute_id else SOURCE_BUCKET_FALLBACK
-    storage_path = f"exam-marker/{cabinet_id}/{file_id}/{safe_name}"
+    # Use the shared users bucket (exists on all envs). Per-institute private buckets
+    # (cc.institutes.<id>.private) are a future multi-tenant provisioning concern and are NOT
+    # created on dev .94 — using one here failed with "Bucket not found". The institute is already
+    # namespaced in the storage path + enforced by RLS on the files row.
+    bucket = SOURCE_BUCKET_FALLBACK
+    storage_path = f"exam-marker/{institute_id or 'noinst'}/{cabinet_id}/{file_id}/{safe_name}"
 
     try:
         storage.upload_file(bucket, storage_path, file_bytes, "application/pdf", upsert=True)