diff --git a/tests/baselines/reference/multipleExportDefault1.errors.txt b/tests/baselines/reference/multipleExportDefault1.errors.txt
new file mode 100644
index 00000000000..3da6afc41e0
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault1.errors.txt
@@ -0,0 +1,19 @@
+tests/cases/conformance/externalModules/multipleExportDefault1.ts(1,25): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault1.ts(5,1): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault1.ts (2 errors) ====
+    export default function Foo (){
+                            ~~~
+!!! error TS2528: A module cannot have multiple default exports.
+        
+    }
+    
+    export default {
+    ~~~~~~~~~~~~~~~~
+        uhoh: "another default",
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    };
+    ~~
+!!! error TS2528: A module cannot have multiple default exports.
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault1.js b/tests/baselines/reference/multipleExportDefault1.js
new file mode 100644
index 00000000000..bec4fb48969
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault1.js
@@ -0,0 +1,20 @@
+//// [multipleExportDefault1.ts]
+export default function Foo (){
+    
+}
+
+export default {
+    uhoh: "another default",
+};
+
+
+//// [multipleExportDefault1.js]
+"use strict";
+function Foo() {
+}
+exports.__esModule = true;
+exports["default"] = Foo;
+exports.__esModule = true;
+exports["default"] = {
+    uhoh: "another default"
+};
diff --git a/tests/baselines/reference/multipleExportDefault2.errors.txt b/tests/baselines/reference/multipleExportDefault2.errors.txt
new file mode 100644
index 00000000000..0543e25a163
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault2.errors.txt
@@ -0,0 +1,18 @@
+tests/cases/conformance/externalModules/multipleExportDefault2.ts(1,1): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault2.ts(5,25): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault2.ts (2 errors) ====
+    export default {
+    ~~~~~~~~~~~~~~~~
+        uhoh: "another default",
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    };
+    ~~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    export default function Foo() { }
+                            ~~~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault2.js b/tests/baselines/reference/multipleExportDefault2.js
new file mode 100644
index 00000000000..dc82500a1d9
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault2.js
@@ -0,0 +1,18 @@
+//// [multipleExportDefault2.ts]
+export default {
+    uhoh: "another default",
+};
+
+export default function Foo() { }
+
+
+
+//// [multipleExportDefault2.js]
+"use strict";
+exports.__esModule = true;
+exports["default"] = {
+    uhoh: "another default"
+};
+function Foo() { }
+exports.__esModule = true;
+exports["default"] = Foo;
diff --git a/tests/baselines/reference/multipleExportDefault3.errors.txt b/tests/baselines/reference/multipleExportDefault3.errors.txt
new file mode 100644
index 00000000000..f1e55da9112
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault3.errors.txt
@@ -0,0 +1,18 @@
+tests/cases/conformance/externalModules/multipleExportDefault3.ts(1,1): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault3.ts(5,22): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault3.ts (2 errors) ====
+    export default {
+    ~~~~~~~~~~~~~~~~
+        uhoh: "another default",
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    };
+    ~~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    export default class C { }
+                         ~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault3.js b/tests/baselines/reference/multipleExportDefault3.js
new file mode 100644
index 00000000000..5d7ad48e0ca
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault3.js
@@ -0,0 +1,22 @@
+//// [multipleExportDefault3.ts]
+export default {
+    uhoh: "another default",
+};
+
+export default class C { }
+
+
+
+//// [multipleExportDefault3.js]
+"use strict";
+exports.__esModule = true;
+exports["default"] = {
+    uhoh: "another default"
+};
+var C = (function () {
+    function C() {
+    }
+    return C;
+}());
+exports.__esModule = true;
+exports["default"] = C;
diff --git a/tests/baselines/reference/multipleExportDefault4.errors.txt b/tests/baselines/reference/multipleExportDefault4.errors.txt
new file mode 100644
index 00000000000..bba15527d00
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault4.errors.txt
@@ -0,0 +1,16 @@
+tests/cases/conformance/externalModules/multipleExportDefault4.ts(1,22): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault4.ts(3,1): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault4.ts (2 errors) ====
+    export default class C { }
+                         ~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    export default {
+    ~~~~~~~~~~~~~~~~
+        uhoh: "another default",
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    };
+    ~~
+!!! error TS2528: A module cannot have multiple default exports.
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault4.js b/tests/baselines/reference/multipleExportDefault4.js
new file mode 100644
index 00000000000..1199fa91c9c
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault4.js
@@ -0,0 +1,20 @@
+//// [multipleExportDefault4.ts]
+export default class C { }
+
+export default {
+    uhoh: "another default",
+};
+
+//// [multipleExportDefault4.js]
+"use strict";
+var C = (function () {
+    function C() {
+    }
+    return C;
+}());
+exports.__esModule = true;
+exports["default"] = C;
+exports.__esModule = true;
+exports["default"] = {
+    uhoh: "another default"
+};
diff --git a/tests/baselines/reference/multipleExportDefault5.errors.txt b/tests/baselines/reference/multipleExportDefault5.errors.txt
new file mode 100644
index 00000000000..30c87339ff2
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault5.errors.txt
@@ -0,0 +1,11 @@
+tests/cases/conformance/externalModules/multipleExportDefault5.ts(1,25): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault5.ts(2,22): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault5.ts (2 errors) ====
+    export default function bar() { }
+                            ~~~
+!!! error TS2528: A module cannot have multiple default exports.
+    export default class C {}
+                         ~
+!!! error TS2528: A module cannot have multiple default exports.
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault5.js b/tests/baselines/reference/multipleExportDefault5.js
new file mode 100644
index 00000000000..7ae33aee9f4
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault5.js
@@ -0,0 +1,16 @@
+//// [multipleExportDefault5.ts]
+export default function bar() { }
+export default class C {}
+
+//// [multipleExportDefault5.js]
+"use strict";
+function bar() { }
+exports.__esModule = true;
+exports["default"] = bar;
+var C = (function () {
+    function C() {
+    }
+    return C;
+}());
+exports.__esModule = true;
+exports["default"] = C;
diff --git a/tests/baselines/reference/multipleExportDefault6.errors.txt b/tests/baselines/reference/multipleExportDefault6.errors.txt
new file mode 100644
index 00000000000..a8bf80e8df0
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault6.errors.txt
@@ -0,0 +1,20 @@
+tests/cases/conformance/externalModules/multipleExportDefault6.ts(1,1): error TS2528: A module cannot have multiple default exports.
+tests/cases/conformance/externalModules/multipleExportDefault6.ts(5,1): error TS2528: A module cannot have multiple default exports.
+
+
+==== tests/cases/conformance/externalModules/multipleExportDefault6.ts (2 errors) ====
+    export default {
+    ~~~~~~~~~~~~~~~~
+        lol: 1
+    ~~~~~~~~~~
+    }
+    ~
+!!! error TS2528: A module cannot have multiple default exports.
+    
+    export default {
+    ~~~~~~~~~~~~~~~~
+        lol: 2
+    ~~~~~~~~~~
+    }
+    ~
+!!! error TS2528: A module cannot have multiple default exports.
\ No newline at end of file
diff --git a/tests/baselines/reference/multipleExportDefault6.js b/tests/baselines/reference/multipleExportDefault6.js
new file mode 100644
index 00000000000..a8b93459e4e
--- /dev/null
+++ b/tests/baselines/reference/multipleExportDefault6.js
@@ -0,0 +1,19 @@
+//// [multipleExportDefault6.ts]
+export default {
+    lol: 1
+}
+
+export default {
+    lol: 2
+}
+
+//// [multipleExportDefault6.js]
+"use strict";
+exports.__esModule = true;
+exports["default"] = {
+    lol: 1
+};
+exports.__esModule = true;
+exports["default"] = {
+    lol: 2
+};
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault1.ts b/tests/cases/conformance/externalModules/multipleExportDefault1.ts
new file mode 100644
index 00000000000..623cc2acc20
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault1.ts
@@ -0,0 +1,7 @@
+export default function Foo (){
+    
+}
+
+export default {
+    uhoh: "another default",
+};
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault2.ts b/tests/cases/conformance/externalModules/multipleExportDefault2.ts
new file mode 100644
index 00000000000..0e14b570aa1
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault2.ts
@@ -0,0 +1,6 @@
+export default {
+    uhoh: "another default",
+};
+
+export default function Foo() { }
+
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault3.ts b/tests/cases/conformance/externalModules/multipleExportDefault3.ts
new file mode 100644
index 00000000000..3b5460e8141
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault3.ts
@@ -0,0 +1,6 @@
+export default {
+    uhoh: "another default",
+};
+
+export default class C { }
+
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault4.ts b/tests/cases/conformance/externalModules/multipleExportDefault4.ts
new file mode 100644
index 00000000000..6181c360798
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault4.ts
@@ -0,0 +1,5 @@
+export default class C { }
+
+export default {
+    uhoh: "another default",
+};
\ No newline at end of file
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault5.ts b/tests/cases/conformance/externalModules/multipleExportDefault5.ts
new file mode 100644
index 00000000000..d2b67fce46f
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault5.ts
@@ -0,0 +1,2 @@
+export default function bar() { }
+export default class C {}
\ No newline at end of file
diff --git a/tests/cases/conformance/externalModules/multipleExportDefault6.ts b/tests/cases/conformance/externalModules/multipleExportDefault6.ts
new file mode 100644
index 00000000000..889ae64376b
--- /dev/null
+++ b/tests/cases/conformance/externalModules/multipleExportDefault6.ts
@@ -0,0 +1,7 @@
+export default {
+    lol: 1
+}
+
+export default {
+    lol: 2
+}
\ No newline at end of file