diff --git a/src/Vervis/Handler/Ticket.hs b/src/Vervis/Handler/Ticket.hs
index dd1f294..b74b9bb 100644
--- a/src/Vervis/Handler/Ticket.hs
+++ b/src/Vervis/Handler/Ticket.hs
@@ -49,7 +49,7 @@ import Data.Traversable (for)
 import Database.Esqueleto hiding ((==.), (=.), (+=.), update)
 import Database.Persist
 import Text.Blaze.Html (Html, toHtml)
-import Yesod.Auth (requireAuthId)
+import Yesod.Auth (requireAuthId, maybeAuthId)
 import Yesod.Core (defaultLayout)
 import Yesod.Core.Handler (setMessage, redirect, lookupPostParam, notFound)
 import Yesod.Form.Functions (runFormGet, runFormPost)
@@ -143,7 +143,7 @@ getTicketNewR shar proj = do
 
 getTicketR :: ShrIdent -> PrjIdent -> Int -> Handler Html
 getTicketR shar proj num = do
-    pid <- requireAuthId
+    mpid <- maybeAuthId
     (author, massignee, closer, ticket) <- runDB $ do
         ticket <- do
             Entity s _ <- getBy404 $ UniqueSharer shar
@@ -156,7 +156,7 @@ getTicketR shar proj num = do
         massignee <- for (ticketAssignee ticket) $ \ apid -> do
             person <- get404 apid
             sharer <- get404 $ personIdent person
-            return (sharer, apid == pid)
+            return (sharer, fromMaybe False $ (== apid) <$> mpid)
         closer <-
             if ticketDone ticket
                 then do