diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index e4f2b0e6da9..16e982bfff3 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -28947,7 +28947,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                             return undefined;
                         }
                     }
-                    return isInJSFile(decl) ? undefined : getTypeOfExpression(binaryExpression.left);
+                    return isInJSFile(decl) || decl === binaryExpression.left ? undefined : getTypeOfExpression(binaryExpression.left);
                 }
             case AssignmentDeclarationKind.ExportsProperty:
             case AssignmentDeclarationKind.Prototype:
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE2.js b/tests/baselines/reference/contextualReturnTypeOfIIFE2.js
new file mode 100644
index 00000000000..c7ea6366750
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE2.js
@@ -0,0 +1,19 @@
+//// [contextualReturnTypeOfIIFE2.ts]
+declare namespace app {
+  function foo(): void;
+}
+
+app.foo.bar = (function () {
+  const someFun = (arg: number) => {};
+  return { someFun };
+})();
+
+app.foo.bar.someFun(1);
+
+
+//// [contextualReturnTypeOfIIFE2.js]
+app.foo.bar = (function () {
+    var someFun = function (arg) { };
+    return { someFun: someFun };
+})();
+app.foo.bar.someFun(1);
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE2.symbols b/tests/baselines/reference/contextualReturnTypeOfIIFE2.symbols
new file mode 100644
index 00000000000..6e7470d4541
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE2.symbols
@@ -0,0 +1,33 @@
+=== tests/cases/compiler/contextualReturnTypeOfIIFE2.ts ===
+declare namespace app {
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE2.ts, 0, 0), Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+
+  function foo(): void;
+>foo : Symbol(foo, Decl(contextualReturnTypeOfIIFE2.ts, 0, 23), Decl(contextualReturnTypeOfIIFE2.ts, 4, 4))
+}
+
+app.foo.bar = (function () {
+>app.foo.bar : Symbol(app.foo.bar, Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+>app.foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE2.ts, 0, 23), Decl(contextualReturnTypeOfIIFE2.ts, 4, 4))
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE2.ts, 0, 0), Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+>foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE2.ts, 0, 23), Decl(contextualReturnTypeOfIIFE2.ts, 4, 4))
+>bar : Symbol(app.foo.bar, Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+
+  const someFun = (arg: number) => {};
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE2.ts, 5, 7))
+>arg : Symbol(arg, Decl(contextualReturnTypeOfIIFE2.ts, 5, 19))
+
+  return { someFun };
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE2.ts, 6, 10))
+
+})();
+
+app.foo.bar.someFun(1);
+>app.foo.bar.someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE2.ts, 6, 10))
+>app.foo.bar : Symbol(app.foo.bar, Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+>app.foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE2.ts, 0, 23), Decl(contextualReturnTypeOfIIFE2.ts, 4, 4))
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE2.ts, 0, 0), Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+>foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE2.ts, 0, 23), Decl(contextualReturnTypeOfIIFE2.ts, 4, 4))
+>bar : Symbol(app.foo.bar, Decl(contextualReturnTypeOfIIFE2.ts, 2, 1))
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE2.ts, 6, 10))
+
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE2.types b/tests/baselines/reference/contextualReturnTypeOfIIFE2.types
new file mode 100644
index 00000000000..2ad9004733e
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE2.types
@@ -0,0 +1,41 @@
+=== tests/cases/compiler/contextualReturnTypeOfIIFE2.ts ===
+declare namespace app {
+>app : typeof app
+
+  function foo(): void;
+>foo : typeof foo
+}
+
+app.foo.bar = (function () {
+>app.foo.bar = (function () {  const someFun = (arg: number) => {};  return { someFun };})() : { someFun: (arg: number) => void; }
+>app.foo.bar : { someFun: (arg: number) => void; }
+>app.foo : typeof app.foo
+>app : typeof app
+>foo : typeof app.foo
+>bar : { someFun: (arg: number) => void; }
+>(function () {  const someFun = (arg: number) => {};  return { someFun };})() : { someFun: (arg: number) => void; }
+>(function () {  const someFun = (arg: number) => {};  return { someFun };}) : () => { someFun: (arg: number) => void; }
+>function () {  const someFun = (arg: number) => {};  return { someFun };} : () => { someFun: (arg: number) => void; }
+
+  const someFun = (arg: number) => {};
+>someFun : (arg: number) => void
+>(arg: number) => {} : (arg: number) => void
+>arg : number
+
+  return { someFun };
+>{ someFun } : { someFun: (arg: number) => void; }
+>someFun : (arg: number) => void
+
+})();
+
+app.foo.bar.someFun(1);
+>app.foo.bar.someFun(1) : void
+>app.foo.bar.someFun : (arg: number) => void
+>app.foo.bar : { someFun: (arg: number) => void; }
+>app.foo : typeof app.foo
+>app : typeof app
+>foo : typeof app.foo
+>bar : { someFun: (arg: number) => void; }
+>someFun : (arg: number) => void
+>1 : 1
+
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE3.js b/tests/baselines/reference/contextualReturnTypeOfIIFE3.js
new file mode 100644
index 00000000000..fc6096bc225
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE3.js
@@ -0,0 +1,21 @@
+//// [contextualReturnTypeOfIIFE3.ts]
+declare namespace app {
+  var foo: {
+    bar: {
+      someFun: (arg: number) => void;
+    };
+  };
+}
+
+app.foo.bar = (function () {
+  return { someFun(arg) {} };
+})();
+
+app.foo.bar.someFun(1);
+
+
+//// [contextualReturnTypeOfIIFE3.js]
+app.foo.bar = (function () {
+    return { someFun: function (arg) { } };
+})();
+app.foo.bar.someFun(1);
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE3.symbols b/tests/baselines/reference/contextualReturnTypeOfIIFE3.symbols
new file mode 100644
index 00000000000..d44c44f894c
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE3.symbols
@@ -0,0 +1,40 @@
+=== tests/cases/compiler/contextualReturnTypeOfIIFE3.ts ===
+declare namespace app {
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE3.ts, 0, 0))
+
+  var foo: {
+>foo : Symbol(foo, Decl(contextualReturnTypeOfIIFE3.ts, 1, 5))
+
+    bar: {
+>bar : Symbol(bar, Decl(contextualReturnTypeOfIIFE3.ts, 1, 12))
+
+      someFun: (arg: number) => void;
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE3.ts, 2, 10))
+>arg : Symbol(arg, Decl(contextualReturnTypeOfIIFE3.ts, 3, 16))
+
+    };
+  };
+}
+
+app.foo.bar = (function () {
+>app.foo.bar : Symbol(bar, Decl(contextualReturnTypeOfIIFE3.ts, 1, 12))
+>app.foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE3.ts, 1, 5))
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE3.ts, 0, 0))
+>foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE3.ts, 1, 5))
+>bar : Symbol(bar, Decl(contextualReturnTypeOfIIFE3.ts, 1, 12))
+
+  return { someFun(arg) {} };
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE3.ts, 9, 10))
+>arg : Symbol(arg, Decl(contextualReturnTypeOfIIFE3.ts, 9, 19))
+
+})();
+
+app.foo.bar.someFun(1);
+>app.foo.bar.someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE3.ts, 2, 10))
+>app.foo.bar : Symbol(bar, Decl(contextualReturnTypeOfIIFE3.ts, 1, 12))
+>app.foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE3.ts, 1, 5))
+>app : Symbol(app, Decl(contextualReturnTypeOfIIFE3.ts, 0, 0))
+>foo : Symbol(app.foo, Decl(contextualReturnTypeOfIIFE3.ts, 1, 5))
+>bar : Symbol(bar, Decl(contextualReturnTypeOfIIFE3.ts, 1, 12))
+>someFun : Symbol(someFun, Decl(contextualReturnTypeOfIIFE3.ts, 2, 10))
+
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE3.types b/tests/baselines/reference/contextualReturnTypeOfIIFE3.types
new file mode 100644
index 00000000000..ba0dd8b2b59
--- /dev/null
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE3.types
@@ -0,0 +1,47 @@
+=== tests/cases/compiler/contextualReturnTypeOfIIFE3.ts ===
+declare namespace app {
+>app : typeof app
+
+  var foo: {
+>foo : { bar: { someFun: (arg: number) => void; }; }
+
+    bar: {
+>bar : { someFun: (arg: number) => void; }
+
+      someFun: (arg: number) => void;
+>someFun : (arg: number) => void
+>arg : number
+
+    };
+  };
+}
+
+app.foo.bar = (function () {
+>app.foo.bar = (function () {  return { someFun(arg) {} };})() : { someFun(arg: number): void; }
+>app.foo.bar : { someFun: (arg: number) => void; }
+>app.foo : { bar: { someFun: (arg: number) => void; }; }
+>app : typeof app
+>foo : { bar: { someFun: (arg: number) => void; }; }
+>bar : { someFun: (arg: number) => void; }
+>(function () {  return { someFun(arg) {} };})() : { someFun(arg: number): void; }
+>(function () {  return { someFun(arg) {} };}) : () => { someFun(arg: number): void; }
+>function () {  return { someFun(arg) {} };} : () => { someFun(arg: number): void; }
+
+  return { someFun(arg) {} };
+>{ someFun(arg) {} } : { someFun(arg: number): void; }
+>someFun : (arg: number) => void
+>arg : number
+
+})();
+
+app.foo.bar.someFun(1);
+>app.foo.bar.someFun(1) : void
+>app.foo.bar.someFun : (arg: number) => void
+>app.foo.bar : { someFun: (arg: number) => void; }
+>app.foo : { bar: { someFun: (arg: number) => void; }; }
+>app : typeof app
+>foo : { bar: { someFun: (arg: number) => void; }; }
+>bar : { someFun: (arg: number) => void; }
+>someFun : (arg: number) => void
+>1 : 1
+
diff --git a/tests/cases/compiler/contextualReturnTypeOfIIFE2.ts b/tests/cases/compiler/contextualReturnTypeOfIIFE2.ts
new file mode 100644
index 00000000000..18416655bb9
--- /dev/null
+++ b/tests/cases/compiler/contextualReturnTypeOfIIFE2.ts
@@ -0,0 +1,13 @@
+// @lib: esnext
+// @noImplicitAny: true
+
+declare namespace app {
+  function foo(): void;
+}
+
+app.foo.bar = (function () {
+  const someFun = (arg: number) => {};
+  return { someFun };
+})();
+
+app.foo.bar.someFun(1);
diff --git a/tests/cases/compiler/contextualReturnTypeOfIIFE3.ts b/tests/cases/compiler/contextualReturnTypeOfIIFE3.ts
new file mode 100644
index 00000000000..6f2ee4e1dd7
--- /dev/null
+++ b/tests/cases/compiler/contextualReturnTypeOfIIFE3.ts
@@ -0,0 +1,16 @@
+// @lib: esnext
+// @noImplicitAny: true
+
+declare namespace app {
+  var foo: {
+    bar: {
+      someFun: (arg: number) => void;
+    };
+  };
+}
+
+app.foo.bar = (function () {
+  return { someFun(arg) {} };
+})();
+
+app.foo.bar.someFun(1);