diff --git a/src/ResponseTypes/MAC.php b/src/ResponseTypes/MAC.php
deleted file mode 100644
index 106d7330..00000000
--- a/src/ResponseTypes/MAC.php
+++ /dev/null
@@ -1,146 +0,0 @@
-<?php
-/**
- * OAuth 2.0 MAC Token Type.
- *
- * @author      Alex Bilbie <hello@alexbilbie.com>
- * @copyright   Copyright (c) Alex Bilbie
- * @license     http://mit-license.org/
- *
- * @link        https://github.com/thephpleague/oauth2-server
- */
-namespace League\OAuth2\Server\TokenTypes;
-
-use League\OAuth2\Server\Util\SecureKey;
-use Symfony\Component\HttpFoundation\ParameterBag;
-use Symfony\Component\HttpFoundation\Request;
-
-/**
- * MAC Token Type.
- */
-class MAC extends AbstractTokenType implements TokenTypeInterface
-{
-    /**
-     * {@inheritdoc}
-     */
-    public function generateResponse()
-    {
-        $macKey = SecureKey::generate();
-        $this->server->getMacStorage()->create($macKey, $this->getParam('access_token'));
-
-        $response = [
-            'access_token'  => $this->getParam('access_token'),
-            'token_type'    => 'mac',
-            'expires_in'    => $this->getParam('expires_in'),
-            'mac_key'       => $macKey,
-            'mac_algorithm' => 'hmac-sha-256',
-        ];
-
-        return $response;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function validateAccessToken(Request $request)
-    {
-        if ($request->headers->has('Authorization') === false) {
-            return;
-        }
-
-        $header = $request->headers->get('Authorization');
-
-        if (substr($header, 0, 4) !== 'MAC ') {
-            return;
-        }
-
-        // Find all the parameters expressed in the header
-        $paramsRaw = explode(',', substr($header, 4));
-        $params = new ParameterBag();
-
-        array_map(function ($param) use (&$params) {
-            $param = trim($param);
-
-            preg_match_all('/([a-zA-Z]*)="([\w=]*)"/', $param, $matches);
-
-            // @codeCoverageIgnoreStart
-            if (count($matches) !== 3) {
-                return;
-            }
-            // @codeCoverageIgnoreEnd
-
-            $key = reset($matches[1]);
-            $value = trim(reset($matches[2]));
-
-            if (empty($value)) {
-                return;
-            }
-
-            $params->set($key, $value);
-        }, $paramsRaw);
-
-        // Validate parameters
-        if ($params->has('id') === false || $params->has('ts') === false || $params->has('nonce') === false || $params->has('mac') === false) {
-            return;
-        }
-
-        if ((int) $params->get('ts') !== time()) {
-            return;
-        }
-
-        $accessToken = $params->get('id');
-        $timestamp = (int) $params->get('ts');
-        $nonce = $params->get('nonce');
-        $signature = $params->get('mac');
-
-        // Try to find the MAC key for the access token
-        $macKey = $this->server->getMacStorage()->getByAccessToken($accessToken);
-
-        if ($macKey === null) {
-            return;
-        }
-
-        // Calculate and compare the signature
-        $calculatedSignatureParts = [
-            $timestamp,
-            $nonce,
-            strtoupper($request->getMethod()),
-            $request->getUri(),
-            $request->getHost(),
-            $request->getPort(),
-        ];
-
-        if ($params->has('ext')) {
-            $calculatedSignatureParts[] = $params->get('ext');
-        }
-
-        $calculatedSignature = base64_encode(hash_hmac('sha256', implode("\n", $calculatedSignatureParts), $macKey));
-
-        // Return the access token if the signature matches
-        return ($this->hash_equals($calculatedSignature, $signature)) ? $accessToken : null;
-    }
-
-    /**
-     * Prevent timing attack.
-     *
-     * @param string $knownString
-     * @param string $userString
-     *
-     * @return bool
-     */
-    private function hash_equals($knownString, $userString)
-    {
-        if (function_exists('\hash_equals')) {
-            return \hash_equals($knownString, $userString);
-        }
-        if (strlen($knownString) !== strlen($userString)) {
-            return false;
-        }
-        $len = strlen($knownString);
-        $result = 0;
-        for ($i = 0; $i < $len; $i++) {
-            $result |= (ord($knownString[$i]) ^ ord($userString[$i]));
-        }
-        // They are only identical strings if $result is exactly 0...
-        return 0 === $result;
-    }
-}