diff --git a/src/core/cs3iface.py b/src/core/cs3iface.py
index a6eed5c8..40d6bba8 100644
--- a/src/core/cs3iface.py
+++ b/src/core/cs3iface.py
@@ -86,7 +86,7 @@ def stat(endpoint, fileid, userid, versioninv=0):
         inode = urlsafe_b64encode(statInfo.info.id.opaque_id.encode())
         return {'inode': statInfo.info.id.storage_id + '-' + inode.decode(),
                 'filepath': statInfo.info.path,
-                'userid': statInfo.info.owner.opaque_id + '@' + statInfo.info.owner.idp,
+                'ownerid': statInfo.info.owner.opaque_id + '@' + statInfo.info.owner.idp,
                 'size': statInfo.info.size,
                 'mtime': statInfo.info.mtime.seconds
                }
diff --git a/src/core/localiface.py b/src/core/localiface.py
index 96f36aa1..cb12659d 100644
--- a/src/core/localiface.py
+++ b/src/core/localiface.py
@@ -53,7 +53,7 @@ def stat(_endpoint, filepath, _userid):
         return {
             'inode': str(statInfo.st_ino),
             'filepath': filepath,
-            'userid': str(statInfo.st_uid) + ':' + str(statInfo.st_gid),
+            'ownerid': str(statInfo.st_uid) + ':' + str(statInfo.st_gid),
             'size': statInfo.st_size,
             'mtime': statInfo.st_mtime
             }
diff --git a/src/core/wopi.py b/src/core/wopi.py
index 52f12c0c..13c6f413 100644
--- a/src/core/wopi.py
+++ b/src/core/wopi.py
@@ -60,7 +60,7 @@ def checkFileInfo(fileid):
         if acctok['viewmode'] in (utils.ViewMode.READ_ONLY, utils.ViewMode.READ_WRITE):
             filemd['DownloadUrl'] = '%s?access_token=%s' % \
                                     (srv.config.get('general', 'downloadurl'), flask.request.args['access_token'])
-        filemd['OwnerId'] = statInfo['userid']
+        filemd['OwnerId'] = statInfo['ownerid']
         filemd['UserId'] = acctok['wopiuser']     # typically same as OwnerId; different when accessing shared documents
         filemd['Size'] = statInfo['size']
         # TODO the version is generated like this in ownCloud: 'V' . $file->getEtag() . \md5($file->getChecksum());
diff --git a/src/core/xrootiface.py b/src/core/xrootiface.py
index 8d1df8b0..54c4b1c7 100644
--- a/src/core/xrootiface.py
+++ b/src/core/xrootiface.py
@@ -156,7 +156,7 @@ def statx(endpoint, filepath, userid, versioninv=0):
         log.debug('msg="Invoked stat return" inode="%s" filepath="%s"' % (inode, _getfilepath(filepath)))
         return {'inode': inode,
                 'filepath': filepath,
-                'userid': statxdata[5] + ':' + statxdata[6],
+                'ownerid': statxdata[5] + ':' + statxdata[6],
                 'size': int(statxdata[8]),
                 'mtime': int(statxdata[12])}
     # now stat the corresponding version folder to get an inode invariant to save operations, see CERNBOX-1216
@@ -189,7 +189,7 @@ def statx(endpoint, filepath, userid, versioninv=0):
     log.debug('msg="Invoked stat return" inode="%s" filepath="%s"' % (inode, _getfilepath(verFolder)))
     return {'inode': inode,
             'filepath': filepath,
-            'userid': statxdata[5] + ':' + statxdata[6],
+            'ownerid': statxdata[5] + ':' + statxdata[6],
             'size': int(statxdata[8]),
             'mtime': int(statxdata[12])}