diff --git a/spdl/bke.spdl b/spdl/bke.spdl
index fbf256a..027e414 100644
--- a/spdl/bke.spdl
+++ b/spdl/bke.spdl
@@ -22,6 +22,7 @@ protocol bkepk(I,R)
 		read_2 (R,I, { hash(ni),nr,R,kir }pk(I) );
 		send_3 (I,R, { hash(nr) }kir );
 		claim_4 (I, Secret, kir );
+		claim_6 (I, Nisynch );
 	}
 
 	role R
@@ -34,6 +35,7 @@ protocol bkepk(I,R)
 		send_2 (R,I, { hash(ni),nr,R,kir }pk(I) );
 		read_3 (I,R, { hash(nr) }kir );
 		claim_5 (R, Secret, kir );
+		claim_7 (R, Nisynch );
 	}
 }