diff --git a/tests/neg/i18448/UBMatch_1.scala b/tests/neg/i18448/UBMatch_1.scala
new file mode 100644
index 000000000000..840626f8450c
--- /dev/null
+++ b/tests/neg/i18448/UBMatch_1.scala
@@ -0,0 +1,2 @@
+type <:![T <: UB, UB] <: UB = T match
+  case UB => T
diff --git a/tests/neg/i18448/UBMatch_2.scala b/tests/neg/i18448/UBMatch_2.scala
new file mode 100644
index 000000000000..becc53e13c7e
--- /dev/null
+++ b/tests/neg/i18448/UBMatch_2.scala
@@ -0,0 +1,3 @@
+trait Foo
+type Of[T] <: Foo = T match
+  case Foo => T <:! Foo