diff --git a/lib/private/json.php b/lib/private/json.php
index 4ccdb490a6c10b05e77f50cbef49bd9f9fc34061..34f81c3b8cf1bfd33a8f9d49ba4e3c8e1f50eed4 100644
--- a/lib/private/json.php
+++ b/lib/private/json.php
@@ -119,8 +119,6 @@ class OC_JSON{
 	* Encode and print $data in json format
 	*/
 	public static function encodedPrint($data, $setContentType=true) {
-		// Disable mimesniffing, don't move this to setContentTypeHeader!
-		header( 'X-Content-Type-Options: nosniff' );
 		if($setContentType) {
 			self::setContentTypeHeader();
 		}
diff --git a/lib/public/appframework/http/jsonresponse.php b/lib/public/appframework/http/jsonresponse.php
index 6628c4514d9c5d473c4840d6b01a52470a363f48..6d029b7464aaface752b692b54f410bf23e15a31 100644
--- a/lib/public/appframework/http/jsonresponse.php
+++ b/lib/public/appframework/http/jsonresponse.php
@@ -49,7 +49,6 @@ class JSONResponse extends Response {
 	public function __construct($data=array(), $statusCode=Http::STATUS_OK) {
 		$this->data = $data;
 		$this->setStatus($statusCode);
-		$this->addHeader('X-Content-Type-Options', 'nosniff');
 		$this->addHeader('Content-type', 'application/json; charset=utf-8');
 	}
 
diff --git a/tests/lib/appframework/http/JSONResponseTest.php b/tests/lib/appframework/http/JSONResponseTest.php
index b9b7c7d63823e18b077375d4ef171f9192c05fd6..fbaae1b922743f4a0ff94bb333bb8890ffdaa01b 100644
--- a/tests/lib/appframework/http/JSONResponseTest.php
+++ b/tests/lib/appframework/http/JSONResponseTest.php
@@ -79,13 +79,6 @@ class JSONResponseTest extends \PHPUnit_Framework_TestCase {
 		$this->assertEquals($expected, $this->json->render());
 	}
 
-
-	public function testShouldHaveXContentHeaderByDefault() {
-		$headers = $this->json->getHeaders();
-		$this->assertEquals('nosniff', $headers['X-Content-Type-Options']);
-	}
-
-
 	public function testConstructorAllowsToSetData() {
 		$data = array('hi');
 		$code = 300;