diff --git a/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/compile-to-class/constructor-collision-ignores-types-loose/output.js b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/compile-to-class/constructor-collision-ignores-types-loose/output.js
new file mode 100644
index 0000000000000..64cb70e748e64
--- /dev/null
+++ b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/compile-to-class/constructor-collision-ignores-types-loose/output.js
@@ -0,0 +1,6 @@
+class C {
+  constructor(T) {
+    this.x = void 0;
+    this.y = 0;
+  }
+}
diff --git a/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/instance-undefined/output.js b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/instance-undefined/output.js
new file mode 100644
index 0000000000000..5da5e4cd518d5
--- /dev/null
+++ b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/instance-undefined/output.js
@@ -0,0 +1,5 @@
+class Foo {
+  constructor() {
+    this.bar = void 0;
+  }
+}
diff --git a/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/preserve-comments/output.js b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/preserve-comments/output.js
new file mode 100644
index 0000000000000..91543cf29c8a9
--- /dev/null
+++ b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/preserve-comments/output.js
@@ -0,0 +1,6 @@
+class C {
+  constructor() {
+    this.a = void 0;
+  }
+}
+C.b = void 0;
diff --git a/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/static-undefined/output.js b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/static-undefined/output.js
new file mode 100644
index 0000000000000..ebc7c89b43f1c
--- /dev/null
+++ b/tasks/transform_conformance/overrides/babel-plugin-transform-class-properties/test/fixtures/public-loose/static-undefined/output.js
@@ -0,0 +1,2 @@
+class Foo {}
+Foo.bar = void 0;