diff --git a/src/scitokens_internal.cpp b/src/scitokens_internal.cpp
index b25608b..c932709 100644
--- a/src/scitokens_internal.cpp
+++ b/src/scitokens_internal.cpp
@@ -584,7 +584,9 @@ Validator::get_public_key_pem(const std::string &issuer, const std::string &kid,
                 get_public_keys_from_web(issuer, SimpleCurlGet::default_timeout, keys, next_update, expires);
                 store_public_keys(issuer, keys, next_update, expires);
             } catch (std::runtime_error &) {
-                // ignore the exception: we have a valid set of keys already/
+                // ignore the exception: we have a valid set of keys already.  However, we don't want to continuously
+                // hammer the upstream server which is not currently working ... move forward the next_update by 5 minutes.
+                store_public_keys(issuer, keys, now + 300, expires);
             }
         }
     } else {