diff --git a/nginx.conf b/nginx.conf
index cbfb0d2..83421d9 100644
--- a/nginx.conf
+++ b/nginx.conf
@@ -43,21 +43,21 @@ http {
     # Common HKP requests.
     location /pks/lookup {
       # sq keyserver get <KEYID>, gpg --receive-keys <KEYID>
-      if ($args ~* "^op=get&options=mr&?search=(0x)?([A-F0-9]{2})([A-F0-9]{14})$") {
+      if ($args ~ "^op=get&options=mr&?search=(0x)?([A-F0-9]{2})([A-F0-9]{14})$") {
         set $dir $2;
         set $file $3;
         rewrite . /by-keyid/$dir/$file;
       }
 
       # gpg --receive-keys <FINGERPRINT>
-      if ($args ~* "^op=get&options=mr&?search=(0x)?([A-F0-9]{2})([A-F0-9]{38})$") {
+      if ($args ~ "^op=get&options=mr&?search=(0x)?([A-F0-9]{2})([A-F0-9]{38})$") {
         set $dir $2;
         set $file $3;
         rewrite . /by-fingerprint/$dir/$file;
       }
 
       # gpg --locate-key <EMAIL>
-      if ($args ~* "^op=get&options=mr&?search=(..)([^&]*)(@|%40)([^&]*)") {
+      if ($args ~ "^op=get&options=mr&?search=(..)([^&]*)(@|%40)([^&]*)") {
         set $dir $1;
         set $local $2;
         set $horst $4;