diff --git a/scripts/tools/easylist-extend.php b/scripts/tools/easylist-extend.php
index fa090598..b86176bc 100644
--- a/scripts/tools/easylist-extend.php
+++ b/scripts/tools/easylist-extend.php
@@ -137,7 +137,7 @@ $ARR_MERGED_WILD_LIST = array(
 
 $ARR_REGEX_LIST = array(
     '/^(\S+\.)?9377[a-z0-9]{2}\.com$/' => ['m' => '$dnstype=A'],
-    '/^(\S+\.)?ad(s?[\d]+|m|s)?\.[0-9\-a-z]+\./i' => ['m' => '$denyallow=nucdn.net|azureedge.net|alibabacorp.com|alibabadns.com'],
+    '/^(\S+\.)?ad(s?[\d]+|m|s)?\.[0-9\-a-z]+\./' => ['m' => '$denyallow=nucdn.net|azureedge.net|alibabacorp.com|alibabadns.com'],
     '/^(\S+\.)?advert/' => ['m' => '$denyallow=alibabacorp.com|alibabadns.com|sm.cn|tanx.com|alibaba-inc.com|tmall.com|taobao.com'],
     '/^(\S+\.)?affiliat(es?[0-9a-z]*?|ion[0-9\-a-z]*?|ly[0-9a-z\-]*?)\./' => null, // fixed #406
     '/^(\S+\.)?s?metrics\./' => null, // TODO 覆盖面很大