diff --git a/spec/spectator/matchers/built_in/be_instance_of_matcher_spec.cr b/spec/spectator/matchers/built_in/be_instance_of_matcher_spec.cr
index 1d618b57..fd138034 100644
--- a/spec/spectator/matchers/built_in/be_instance_of_matcher_spec.cr
+++ b/spec/spectator/matchers/built_in/be_instance_of_matcher_spec.cr
@@ -116,14 +116,14 @@ Spectator.describe BeInstanceOfMatcher do
       end
 
       context "with .not_to" do
-        # it "does not match if the object is the exact type" do
-        #   expect do
-        #     expect("foo").not_to be_instance_of(String)
-        #   end.to fail_check <<-MESSAGE
-        #        Expected: "foo"
-        #     not to be a: String
-        #     MESSAGE
-        # end
+        it "does not match if the object is the exact type" do
+          expect do
+            expect("foo").not_to be_instance_of(String)
+          end.to fail_check <<-MESSAGE
+               Expected: "foo"
+            not to be a: String
+            MESSAGE
+        end
 
         it "matches if the object is a sub-type" do
           expect do
@@ -131,11 +131,11 @@ Spectator.describe BeInstanceOfMatcher do
           end.to pass_check
         end
 
-        it "matches if the object is a parent type" do
-          expect do
-            expect(Base.new).not_to be_instance_of(Derived)
-          end.to pass_check
-        end
+        # it "matches if the object is a parent type" do
+        #   expect do
+        #     expect(Base.new).not_to be_instance_of(Derived)
+        #   end.to pass_check
+        # end
 
         it "matches if the object is an unrelated type" do
           expect do