diff --git a/Owin.Security.Providers/OpenID/OpenIDAuthenticationHandler.cs b/Owin.Security.Providers/OpenID/OpenIDAuthenticationHandler.cs
index 7b9e26b..342ed5e 100644
--- a/Owin.Security.Providers/OpenID/OpenIDAuthenticationHandler.cs
+++ b/Owin.Security.Providers/OpenID/OpenIDAuthenticationHandler.cs
@@ -247,10 +247,14 @@ namespace Owin.Security.Providers.OpenID
                 {
                     nameValue = lastValue;
                 }
-                else
+                else if (!string.IsNullOrEmpty(emailValue) && emailValue.Contains("@"))
                 {
                     nameValue = emailValue.Substring(0, emailValue.IndexOf('@'));
                 }
+                else
+                {
+                    nameValue = claimedID;
+                }
             }
 
             identity.AddClaim(new Claim(ClaimTypes.Name, nameValue, "http://www.w3.org/2001/XMLSchema#string", Options.AuthenticationType));