diff --git a/restapi/index.php b/restapi/index.php
index 74e5f637b..7f1eefb75 100644
--- a/restapi/index.php
+++ b/restapi/index.php
@@ -595,6 +595,13 @@ class RestapiController { /* {{{ */
             return $response->withJson(array('success'=>false, 'message'=>'No parent folder id given', 'data'=>''), 400);
         }
 
+				if($settings->_quota > 0) {
+					$remain = checkQuota($userobj);
+					if ($remain < 0) {
+            return $response->withJson(array('success'=>false, 'message'=>'Quota exceeded', 'data'=>''), 400);
+					}
+				}
+
         $mfolder = $dms->getFolder($args['id']);
         if($mfolder) {
             $uploadedFiles = $request->getUploadedFiles();
@@ -692,6 +699,7 @@ class RestapiController { /* {{{ */
     function updateDocument($request, $response, $args) { /* {{{ */
         $dms = $this->container->dms;
         $userobj = $this->container->userobj;
+        $settings = $this->container->config;
 
         if(!$userobj) {
             return $response->withJson(array('success'=>false, 'message'=>'Not logged in', 'data'=>''), 403);
@@ -701,6 +709,13 @@ class RestapiController { /* {{{ */
             return $response->withJson(array('success'=>false, 'message'=>'No document id given', 'data'=>''), 400);
         }
 
+				if($settings->_quota > 0) {
+					$remain = checkQuota($userobj);
+					if ($remain < 0) {
+            return $response->withJson(array('success'=>false, 'message'=>'Quota exceeded', 'data'=>''), 400);
+					}
+				}
+
         $document = $dms->getDocument($args['id']);
         if($document) {
             if ($document->getAccessMode($userobj, 'updateDocument') >= M_READWRITE) {
@@ -726,7 +741,13 @@ class RestapiController { /* {{{ */
                 $file_info = array_pop($uploadedFiles);
                 if ($origfilename == null)
                     $origfilename = $file_info->getClientFilename();
-                $temp = $file_info->file;
+								$temp = $file_info->file;
+
+								/* Check if the uploaded file is identical to last version */
+								$lc = $document->getLatestContent();
+								if($lc->getChecksum() == SeedDMS_Core_File::checksum($temp)) {
+									return $response->withJson(array('success'=>false, 'message'=>'Uploaded file identical to last version', 'data'=>''), 400);
+								}
                 $finfo = finfo_open(FILEINFO_MIME_TYPE);
                 $userfiletype = finfo_file($finfo, $temp);
                 $fileType = ".".pathinfo($origfilename, PATHINFO_EXTENSION);
@@ -762,7 +783,15 @@ class RestapiController { /* {{{ */
 
         if(!ctype_digit($args['id']) || $args['id'] == 0) {
             return $response->withJson(array('success'=>false, 'message'=>'No document id given', 'data'=>''), 400);
-        }
+				}
+
+				if($settings->_quota > 0) {
+					$remain = checkQuota($userobj);
+					if ($remain < 0) {
+            return $response->withJson(array('success'=>false, 'message'=>'Quota exceeded', 'data'=>''), 400);
+					}
+				}
+
         $mfolder = $dms->getFolder($args['id']);
         if($mfolder) {
             if ($mfolder->getAccessMode($userobj, 'addDocument') >= M_READWRITE) {