diff --git a/src/TPDB/CPF/Proof/Write.hs b/src/TPDB/CPF/Proof/Write.hs
--- a/src/TPDB/CPF/Proof/Write.hs
+++ b/src/TPDB/CPF/Proof/Write.hs
@@ -171,11 +171,10 @@
 instance XmlContent (TrsTerminationProof Relative) where
    parseContents = error "parseContents not implemented"
 
+   toContents p@SIsEmpty{} = 
+          toContents $ trsTerminationProof_Standard p
    toContents p = rmkel "trsTerminationProof" $ case p of
       RIsEmpty -> rmkel "rIsEmpty" []
-      SIsEmpty {} -> rmkel "sIsEmpty" $ concat
-          [ toContents $ trsTerminationProof_Standard p
-          ]
       StringReversal {} -> rmkel "stringReversal" $ concat
           [ toContents $ trs p
           , toContents $ trsTerminationProof p
diff --git a/tpdb.cabal b/tpdb.cabal
--- a/tpdb.cabal
+++ b/tpdb.cabal
@@ -1,7 +1,7 @@
 Cabal-Version: 3.8
 
 Name: tpdb
-Version: 2.8.5
+Version: 2.8.6
 
 Author: Alexander Bau, Johannes Waldmann
 Maintainer: Johannes Waldmann