diff --git a/api.php b/api.php
index dd74f26..da6459d 100755
--- a/api.php
+++ b/api.php
@@ -65,6 +65,8 @@ OR OTHER DEALINGS IN THE SOFTWARE.
  *     }
  */
 
+use Arionum\Blacklist;
+
 require_once("include/init.inc.php");
 error_reporting(0);
 $ip = san_ip($_SERVER['REMOTE_ADDR']);
@@ -429,10 +431,7 @@ if ($q == "getAddress") {
         api_err("Invalid public key");
     }
     if ($_config['use_official_blacklist']!==false) {
-        $blacklisted=["PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCvVQcHHCNLfiP9LmzWhhpCHx39Bhc67P5HMQM9cctEFvcsUdgrkGqy18taz9ZMrAGtq7NhBYpQ4ZTHkKYiZDaSUqQ", //faucet abuser
-        "PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCxYDeQHk7Ke66UB2Un3UMmMoJ7RF5vDZXihdEXi8gk8ZBRAi35aFrER2ZLX1mgND7sLFXKETGTjRYjoHcuRNiJN1g" // octaex
-        ];
-        if (in_array($public_key, $blacklisted)) {
+        if (Blacklist::checkPublicKey($public_key)) {
             api_err("Blacklisted account");
         }
     }
diff --git a/include/Blacklist.php b/include/Blacklist.php
new file mode 100644
index 0000000..0545778
--- /dev/null
+++ b/include/Blacklist.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Arionum;
+
+/**
+ * Class Blacklist
+ */
+final class Blacklist
+{
+    /**
+     * The official list of blacklisted public keys
+     */
+    public const PUBLIC_KEYS = [
+        // phpcs:disable Generic.Files.LineLength
+        'PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCvVQcHHCNLfiP9LmzWhhpCHx39Bhc67P5HMQM9cctEFvcsUdgrkGqy18taz9ZMrAGtq7NhBYpQ4ZTHkKYiZDaSUqQ' => 'Faucet Abuser',
+        'PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCxYDeQHk7Ke66UB2Un3UMmMoJ7RF5vDZXihdEXi8gk8ZBRAi35aFrER2ZLX1mgND7sLFXKETGTjRYjoHcuRNiJN1g' => 'Octaex Exchange',
+        // phpcs:enable
+    ];
+
+    /**
+     * Check if a public key is blacklisted
+     *
+     * @param string $publicKey
+     * @return bool
+     */
+    public static function checkPublicKey(string $publicKey): bool
+    {
+        return key_exists($publicKey, static::PUBLIC_KEYS);
+    }
+}
diff --git a/include/init.inc.php b/include/init.inc.php
index cae142d..a0171eb 100755
--- a/include/init.inc.php
+++ b/include/init.inc.php
@@ -16,6 +16,7 @@ if (php_sapi_name() !== 'cli' && substr_count($_SERVER['PHP_SELF'], "/") > 1) {
 require_once("include/config.inc.php");
 require_once("include/db.inc.php");
 require_once("include/functions.inc.php");
+require_once __DIR__.'/Blacklist.php';
 require_once("include/block.inc.php");
 require_once("include/account.inc.php");
 require_once("include/transaction.inc.php");
diff --git a/include/transaction.inc.php b/include/transaction.inc.php
index 48bfadd..f718de4 100755
--- a/include/transaction.inc.php
+++ b/include/transaction.inc.php
@@ -1,5 +1,7 @@
 <?php
 
+use Arionum\Blacklist;
+
 class Transaction
 {
     // reverse and remove all transactions from a block
@@ -225,11 +227,7 @@ class Transaction
         }
         
         if ($_config['use_official_blacklist']!==false) {
-            $blacklisted=[
-                "PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCvVQcHHCNLfiP9LmzWhhpCHx39Bhc67P5HMQM9cctEFvcsUdgrkGqy18taz9ZMrAGtq7NhBYpQ4ZTHkKYiZDaSUqQ", //faucet abuser
-                "PZ8Tyr4Nx8MHsRAGMpZmZ6TWY63dXWSCxYDeQHk7Ke66UB2Un3UMmMoJ7RF5vDZXihdEXi8gk8ZBRAi35aFrER2ZLX1mgND7sLFXKETGTjRYjoHcuRNiJN1g" // octaex
-            ];
-            if (in_array($x['public_key'], $blacklisted)) {
+            if (Blacklist::checkPublicKey($x['public_key'])) {
                 return true;
             }
         }