diff --git a/tests/AbstractSignatureMethodTest.php b/tests/AbstractSignatureMethodTest.php
index ca381cfa..60a2a7f5 100644
--- a/tests/AbstractSignatureMethodTest.php
+++ b/tests/AbstractSignatureMethodTest.php
@@ -13,7 +13,7 @@ abstract class AbstractSignatureMethodTest extends \PHPUnit_Framework_TestCase
      */
     abstract public function getClass();
 
-    abstract function signatureDataProvider();
+    abstract protected function signatureDataProvider();
 
     public function testGetName()
     {
@@ -48,4 +48,4 @@ protected function getToken($key = null, $secret = null)
             ->setConstructorArgs(array($key, $secret))
             ->getMock();
     }
-}
\ No newline at end of file
+}