diff --git a/endpoints/key_server.py b/endpoints/key_server.py
index 1d88c3689..c5522d0da 100644
--- a/endpoints/key_server.py
+++ b/endpoints/key_server.py
@@ -97,13 +97,19 @@ def get_service_key(service, kid):
 
 @key_server.route('/services/<service>/keys/<kid>', methods=['PUT'])
 def put_service_keys(service, kid):
+  metadata = {'ip': request.remote_addr}
+
   expiration_date = request.args.get('expiration', None)
-  if expiration_date:
+  if expiration_date is not None:
     try:
       expiration_date = datetime.utcfromtimestamp(float(expiration_date))
     except ValueError:
       abort(400)
 
+  rotation_ttl = request.args.get('rotation', None)
+  if rotation_ttl is not None:
+    metadata['rotation_ttl'] = rotation_ttl
+
   try:
     jwk = request.get_json()
   except ValueError:
@@ -119,7 +125,6 @@ def put_service_keys(service, kid):
 
   _validate_jwk(jwk, kid)
 
-  metadata = {'ip': request.remote_addr}
   signer_kid = _signer_kid(encoded_jwt)
 
   if kid == signer_kid or signer_kid is None: