diff --git a/sbysrc/sby_core.py b/sbysrc/sby_core.py
index c181c18..e502fe8 100644
--- a/sbysrc/sby_core.py
+++ b/sbysrc/sby_core.py
@@ -1020,7 +1020,7 @@ class SbyTask(SbyConfig):
                     if self.opt_mode in ["bmc", "prove"]:
                         print("chformal -live -fair -cover -remove", file=f)
                     if self.opt_mode == "cover":
-                        print("chformal -live -fair -remove", file=f)
+                        print("chformal -live -fair -assert -remove", file=f)
                     if self.opt_mode == "live":
                         print("chformal -assert2assume", file=f)
                         print("chformal -cover -remove", file=f)
diff --git a/tests/unsorted/mixed.sby b/tests/unsorted/mixed.sby
index 2d9467e..4948af0 100644
--- a/tests/unsorted/mixed.sby
+++ b/tests/unsorted/mixed.sby
@@ -8,6 +8,9 @@ cover: mode cover
 bmc: mode bmc
 bmc: depth 1
 
+cover: expect pass
+~cover: expect fail
+
 [engines]
 cover: btor btormc
 btormc: btor btormc
diff --git a/tests/unsorted/mixed.v b/tests/unsorted/mixed.v
index 26bf3c9..16e1228 100644
--- a/tests/unsorted/mixed.v
+++ b/tests/unsorted/mixed.v
@@ -3,7 +3,7 @@ module test (input CP, CN, input A, B, output reg XP, XN);
 	always @* begin
 		assume (A || B);
 		assume (!A || !B);
-		assert (A != B);
+		assert (A == B);
 		cover (counter == 3 && A);
 		cover (counter == 3 && B);
 	end