diff --git a/server.py b/server.py
index 3fe33ab..18fa263 100644
--- a/server.py
+++ b/server.py
@@ -64,10 +64,9 @@ class fuwuqi(SimpleHTTPRequestHandler):
 
         username = search('^/users/(.*)\.(in|out)box$', self.path).group(1)
 
-        # Get actor public key
-        keyid = search('keyId="(.*?)"', self.headers['Signature']).group(1)
-        actor = iri_to_actor(keyid)
-        pubkeypem = actor['publicKey']['publicKeyPem'].encode('utf8')
+        # Get signer public key
+        signer = iri_to_actor(search('keyId="(.*?)"', self.headers['Signature']).group(1))
+        pubkeypem = signer['publicKey']['publicKeyPem'].encode('utf8')
         pubkey = serialization.load_pem_public_key(pubkeypem, None)
 
         # Assemble headers
@@ -84,11 +83,10 @@ class fuwuqi(SimpleHTTPRequestHandler):
         signature = search('signature="(.*?)"', self.headers['Signature']).group(1)
         pubkey.verify(b64decode(signature), message[:-1].encode('utf8'), padding.PKCS1v15(), hashes.SHA256())
 
-        # Make sure activity doer matches HTTP signature
-        actor = keyid.removesuffix('#main-key')
-        if ('actor' in activity and activity['actor'] != actor) or \
-           ('attributedTo' in activity and activity['attributedTo'] != actor) or \
-           ('attributedTo' in activity['object'] and activity['object']['attributedTo'] != actor):
+        # Make sure activity doer matches HTTP signature 
+        if ('actor' in activity and activity['actor'] != signer['id']) or \
+           ('attributedTo' in activity and activity['attributedTo'] != signer['id']) or \
+           ('attributedTo' in activity['object'] and activity['object']['attributedTo'] != signer['id']):
             self.send_response(401)
             return