diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 12b55aa818b..5fe3a0de1a5 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -12754,11 +12754,6 @@ namespace ts {
                     // Props is of type 'any' or unknown
                     return attributesType;
                 }
-                else if (attributesType.flags & TypeFlags.Union) {
-                    // Props cannot be a union type
-                    error(openingLikeElement.tagName, Diagnostics.JSX_element_attributes_type_0_may_not_be_a_union_type, typeToString(attributesType));
-                    return anyType;
-                }
                 else {
                     // Normal case -- add in IntrinsicClassElements<T> and IntrinsicElements
                     let apparentAttributesType = attributesType;
diff --git a/tests/baselines/reference/tsxAttributeResolution16.js b/tests/baselines/reference/tsxAttributeResolution16.js
new file mode 100644
index 00000000000..1182c886b94
--- /dev/null
+++ b/tests/baselines/reference/tsxAttributeResolution16.js
@@ -0,0 +1,53 @@
+//// [file.tsx]
+
+import React = require('react');
+
+interface Address {
+  street: string;
+  country: string;
+}
+
+interface CanadianAddress extends Address {
+    postalCode: string;
+}
+
+interface AmericanAddress extends Address {
+    zipCode: string;
+}
+
+type Properties = CanadianAddress | AmericanAddress;
+
+export class AddressComp extends React.Component<Properties, void> {
+  public render() {
+    return null;
+  }
+}
+
+let a = <AddressComp postalCode='T1B 0L3' street="vancouver" country="CA" />
+
+//// [file.jsx]
+"use strict";
+var __extends = (this && this.__extends) || (function () {
+    var extendStatics = Object.setPrototypeOf ||
+        ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
+        function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
+    return function (d, b) {
+        extendStatics(d, b);
+        function __() { this.constructor = d; }
+        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+    };
+})();
+exports.__esModule = true;
+var React = require("react");
+var AddressComp = (function (_super) {
+    __extends(AddressComp, _super);
+    function AddressComp() {
+        return _super !== null && _super.apply(this, arguments) || this;
+    }
+    AddressComp.prototype.render = function () {
+        return null;
+    };
+    return AddressComp;
+}(React.Component));
+exports.AddressComp = AddressComp;
+var a = <AddressComp postalCode='T1B 0L3' street="vancouver" country="CA"/>;
diff --git a/tests/baselines/reference/tsxAttributeResolution16.symbols b/tests/baselines/reference/tsxAttributeResolution16.symbols
new file mode 100644
index 00000000000..0c271566de9
--- /dev/null
+++ b/tests/baselines/reference/tsxAttributeResolution16.symbols
@@ -0,0 +1,57 @@
+=== tests/cases/conformance/jsx/file.tsx ===
+
+import React = require('react');
+>React : Symbol(React, Decl(file.tsx, 0, 0))
+
+interface Address {
+>Address : Symbol(Address, Decl(file.tsx, 1, 32))
+
+  street: string;
+>street : Symbol(Address.street, Decl(file.tsx, 3, 19))
+
+  country: string;
+>country : Symbol(Address.country, Decl(file.tsx, 4, 17))
+}
+
+interface CanadianAddress extends Address {
+>CanadianAddress : Symbol(CanadianAddress, Decl(file.tsx, 6, 1))
+>Address : Symbol(Address, Decl(file.tsx, 1, 32))
+
+    postalCode: string;
+>postalCode : Symbol(CanadianAddress.postalCode, Decl(file.tsx, 8, 43))
+}
+
+interface AmericanAddress extends Address {
+>AmericanAddress : Symbol(AmericanAddress, Decl(file.tsx, 10, 1))
+>Address : Symbol(Address, Decl(file.tsx, 1, 32))
+
+    zipCode: string;
+>zipCode : Symbol(AmericanAddress.zipCode, Decl(file.tsx, 12, 43))
+}
+
+type Properties = CanadianAddress | AmericanAddress;
+>Properties : Symbol(Properties, Decl(file.tsx, 14, 1))
+>CanadianAddress : Symbol(CanadianAddress, Decl(file.tsx, 6, 1))
+>AmericanAddress : Symbol(AmericanAddress, Decl(file.tsx, 10, 1))
+
+export class AddressComp extends React.Component<Properties, void> {
+>AddressComp : Symbol(AddressComp, Decl(file.tsx, 16, 52))
+>React.Component : Symbol(React.Component, Decl(react.d.ts, 158, 55))
+>React : Symbol(React, Decl(file.tsx, 0, 0))
+>Component : Symbol(React.Component, Decl(react.d.ts, 158, 55))
+>Properties : Symbol(Properties, Decl(file.tsx, 14, 1))
+
+  public render() {
+>render : Symbol(AddressComp.render, Decl(file.tsx, 18, 68))
+
+    return null;
+  }
+}
+
+let a = <AddressComp postalCode='T1B 0L3' street="vancouver" country="CA" />
+>a : Symbol(a, Decl(file.tsx, 24, 3))
+>AddressComp : Symbol(AddressComp, Decl(file.tsx, 16, 52))
+>postalCode : Symbol(postalCode, Decl(file.tsx, 24, 20))
+>street : Symbol(street, Decl(file.tsx, 24, 41))
+>country : Symbol(country, Decl(file.tsx, 24, 60))
+
diff --git a/tests/baselines/reference/tsxAttributeResolution16.types b/tests/baselines/reference/tsxAttributeResolution16.types
new file mode 100644
index 00000000000..68134d7ac2d
--- /dev/null
+++ b/tests/baselines/reference/tsxAttributeResolution16.types
@@ -0,0 +1,59 @@
+=== tests/cases/conformance/jsx/file.tsx ===
+
+import React = require('react');
+>React : typeof React
+
+interface Address {
+>Address : Address
+
+  street: string;
+>street : string
+
+  country: string;
+>country : string
+}
+
+interface CanadianAddress extends Address {
+>CanadianAddress : CanadianAddress
+>Address : Address
+
+    postalCode: string;
+>postalCode : string
+}
+
+interface AmericanAddress extends Address {
+>AmericanAddress : AmericanAddress
+>Address : Address
+
+    zipCode: string;
+>zipCode : string
+}
+
+type Properties = CanadianAddress | AmericanAddress;
+>Properties : CanadianAddress | AmericanAddress
+>CanadianAddress : CanadianAddress
+>AmericanAddress : AmericanAddress
+
+export class AddressComp extends React.Component<Properties, void> {
+>AddressComp : AddressComp
+>React.Component : React.Component<CanadianAddress | AmericanAddress, void>
+>React : typeof React
+>Component : typeof React.Component
+>Properties : CanadianAddress | AmericanAddress
+
+  public render() {
+>render : () => any
+
+    return null;
+>null : null
+  }
+}
+
+let a = <AddressComp postalCode='T1B 0L3' street="vancouver" country="CA" />
+>a : JSX.Element
+><AddressComp postalCode='T1B 0L3' street="vancouver" country="CA" /> : JSX.Element
+>AddressComp : typeof AddressComp
+>postalCode : string
+>street : string
+>country : string
+
diff --git a/tests/baselines/reference/tsxSpreadAttributesResolution6.errors.txt b/tests/baselines/reference/tsxSpreadAttributesResolution6.errors.txt
index c3bd7484fbf..968fa3764a8 100644
--- a/tests/baselines/reference/tsxSpreadAttributesResolution6.errors.txt
+++ b/tests/baselines/reference/tsxSpreadAttributesResolution6.errors.txt
@@ -1,4 +1,7 @@
-tests/cases/conformance/jsx/file.tsx(14,10): error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
+tests/cases/conformance/jsx/file.tsx(14,24): error TS2322: Type '{ editable: true; }' is not assignable to type '(IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: false; } & { children?: ReactNode; }) | (IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })'.
+  Type '{ editable: true; }' is not assignable to type 'IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; }'.
+    Type '{ editable: true; }' is not assignable to type '{ editable: true; onEdit: (newText: string) => void; }'.
+      Property 'onEdit' is missing in type '{ editable: true; }'.
 
 
 ==== tests/cases/conformance/jsx/file.tsx (1 errors) ====
@@ -16,8 +19,11 @@ tests/cases/conformance/jsx/file.tsx(14,10): error TS2600: JSX element attribute
     
     // Error
     let x = <TextComponent editable={true} />
-             ~~~~~~~~~~~~~
-!!! error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
+                           ~~~~~~~~~~~~~~~
+!!! error TS2322: Type '{ editable: true; }' is not assignable to type '(IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: false; } & { children?: ReactNode; }) | (IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })'.
+!!! error TS2322:   Type '{ editable: true; }' is not assignable to type 'IntrinsicAttributes & IntrinsicClassAttributes<TextComponent> & { editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; }'.
+!!! error TS2322:     Type '{ editable: true; }' is not assignable to type '{ editable: true; onEdit: (newText: string) => void; }'.
+!!! error TS2322:       Property 'onEdit' is missing in type '{ editable: true; }'.
     
     const textProps: TextProps = {
         editable: false
diff --git a/tests/baselines/reference/tsxSpreadAttributesResolution7.errors.txt b/tests/baselines/reference/tsxSpreadAttributesResolution7.errors.txt
deleted file mode 100644
index c71459c4a38..00000000000
--- a/tests/baselines/reference/tsxSpreadAttributesResolution7.errors.txt
+++ /dev/null
@@ -1,34 +0,0 @@
-tests/cases/conformance/jsx/file.tsx(18,11): error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
-tests/cases/conformance/jsx/file.tsx(25,11): error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
-
-
-==== tests/cases/conformance/jsx/file.tsx (2 errors) ====
-    
-    import React = require('react');
-    
-    type TextProps = { editable: false }
-                   | { editable: true, onEdit: (newText: string) => void };
-    
-    class TextComponent extends React.Component<TextProps, {}> {
-        render() {
-            return <span>Some Text..</span>;
-        }
-    }
-    
-    // OK
-    const textPropsFalse: TextProps = {
-        editable: false
-    };
-    
-    let y1 = <TextComponent {...textPropsFalse} />
-              ~~~~~~~~~~~~~
-!!! error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
-    
-    const textPropsTrue: TextProps = {
-        editable: true,
-        onEdit: () => {}
-    };
-    
-    let y2 = <TextComponent {...textPropsTrue} />
-              ~~~~~~~~~~~~~
-!!! error TS2600: JSX element attributes type '({ editable: false; } & { children?: ReactNode; }) | ({ editable: true; onEdit: (newText: string) => void; } & { children?: ReactNode; })' may not be a union type.
\ No newline at end of file
diff --git a/tests/baselines/reference/tsxSpreadAttributesResolution7.symbols b/tests/baselines/reference/tsxSpreadAttributesResolution7.symbols
new file mode 100644
index 00000000000..f40b79ae616
--- /dev/null
+++ b/tests/baselines/reference/tsxSpreadAttributesResolution7.symbols
@@ -0,0 +1,62 @@
+=== tests/cases/conformance/jsx/file.tsx ===
+
+import React = require('react');
+>React : Symbol(React, Decl(file.tsx, 0, 0))
+
+type TextProps = { editable: false }
+>TextProps : Symbol(TextProps, Decl(file.tsx, 1, 32))
+>editable : Symbol(editable, Decl(file.tsx, 3, 18))
+
+               | { editable: true, onEdit: (newText: string) => void };
+>editable : Symbol(editable, Decl(file.tsx, 4, 18))
+>onEdit : Symbol(onEdit, Decl(file.tsx, 4, 34))
+>newText : Symbol(newText, Decl(file.tsx, 4, 44))
+
+class TextComponent extends React.Component<TextProps, {}> {
+>TextComponent : Symbol(TextComponent, Decl(file.tsx, 4, 71))
+>React.Component : Symbol(React.Component, Decl(react.d.ts, 158, 55))
+>React : Symbol(React, Decl(file.tsx, 0, 0))
+>Component : Symbol(React.Component, Decl(react.d.ts, 158, 55))
+>TextProps : Symbol(TextProps, Decl(file.tsx, 1, 32))
+
+    render() {
+>render : Symbol(TextComponent.render, Decl(file.tsx, 6, 60))
+
+        return <span>Some Text..</span>;
+>span : Symbol(JSX.IntrinsicElements.span, Decl(react.d.ts, 2458, 51))
+>span : Symbol(JSX.IntrinsicElements.span, Decl(react.d.ts, 2458, 51))
+    }
+}
+
+// OK
+const textPropsFalse: TextProps = {
+>textPropsFalse : Symbol(textPropsFalse, Decl(file.tsx, 13, 5))
+>TextProps : Symbol(TextProps, Decl(file.tsx, 1, 32))
+
+    editable: false
+>editable : Symbol(editable, Decl(file.tsx, 13, 35))
+
+};
+
+let y1 = <TextComponent {...textPropsFalse} />
+>y1 : Symbol(y1, Decl(file.tsx, 17, 3))
+>TextComponent : Symbol(TextComponent, Decl(file.tsx, 4, 71))
+>textPropsFalse : Symbol(textPropsFalse, Decl(file.tsx, 13, 5))
+
+const textPropsTrue: TextProps = {
+>textPropsTrue : Symbol(textPropsTrue, Decl(file.tsx, 19, 5))
+>TextProps : Symbol(TextProps, Decl(file.tsx, 1, 32))
+
+    editable: true,
+>editable : Symbol(editable, Decl(file.tsx, 19, 34))
+
+    onEdit: () => {}
+>onEdit : Symbol(onEdit, Decl(file.tsx, 20, 19))
+
+};
+
+let y2 = <TextComponent {...textPropsTrue} />
+>y2 : Symbol(y2, Decl(file.tsx, 24, 3))
+>TextComponent : Symbol(TextComponent, Decl(file.tsx, 4, 71))
+>textPropsTrue : Symbol(textPropsTrue, Decl(file.tsx, 19, 5))
+
diff --git a/tests/baselines/reference/tsxSpreadAttributesResolution7.types b/tests/baselines/reference/tsxSpreadAttributesResolution7.types
new file mode 100644
index 00000000000..db423de0904
--- /dev/null
+++ b/tests/baselines/reference/tsxSpreadAttributesResolution7.types
@@ -0,0 +1,72 @@
+=== tests/cases/conformance/jsx/file.tsx ===
+
+import React = require('react');
+>React : typeof React
+
+type TextProps = { editable: false }
+>TextProps : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+>editable : false
+>false : false
+
+               | { editable: true, onEdit: (newText: string) => void };
+>editable : true
+>true : true
+>onEdit : (newText: string) => void
+>newText : string
+
+class TextComponent extends React.Component<TextProps, {}> {
+>TextComponent : TextComponent
+>React.Component : React.Component<{ editable: false; } | { editable: true; onEdit: (newText: string) => void; }, {}>
+>React : typeof React
+>Component : typeof React.Component
+>TextProps : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+
+    render() {
+>render : () => JSX.Element
+
+        return <span>Some Text..</span>;
+><span>Some Text..</span> : JSX.Element
+>span : any
+>span : any
+    }
+}
+
+// OK
+const textPropsFalse: TextProps = {
+>textPropsFalse : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+>TextProps : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+>{    editable: false} : { editable: false; }
+
+    editable: false
+>editable : boolean
+>false : false
+
+};
+
+let y1 = <TextComponent {...textPropsFalse} />
+>y1 : JSX.Element
+><TextComponent {...textPropsFalse} /> : JSX.Element
+>TextComponent : typeof TextComponent
+>textPropsFalse : { editable: false; }
+
+const textPropsTrue: TextProps = {
+>textPropsTrue : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+>TextProps : { editable: false; } | { editable: true; onEdit: (newText: string) => void; }
+>{    editable: true,    onEdit: () => {}} : { editable: true; onEdit: () => void; }
+
+    editable: true,
+>editable : boolean
+>true : true
+
+    onEdit: () => {}
+>onEdit : () => void
+>() => {} : () => void
+
+};
+
+let y2 = <TextComponent {...textPropsTrue} />
+>y2 : JSX.Element
+><TextComponent {...textPropsTrue} /> : JSX.Element
+>TextComponent : typeof TextComponent
+>textPropsTrue : { editable: true; onEdit: (newText: string) => void; }
+
diff --git a/tests/cases/conformance/jsx/tsxAttributeResolution16.tsx b/tests/cases/conformance/jsx/tsxAttributeResolution16.tsx
new file mode 100644
index 00000000000..811a1b47174
--- /dev/null
+++ b/tests/cases/conformance/jsx/tsxAttributeResolution16.tsx
@@ -0,0 +1,29 @@
+// @filename: file.tsx
+// @jsx: preserve
+// @noLib: true
+// @libFiles: react.d.ts,lib.d.ts
+
+import React = require('react');
+
+interface Address {
+  street: string;
+  country: string;
+}
+
+interface CanadianAddress extends Address {
+    postalCode: string;
+}
+
+interface AmericanAddress extends Address {
+    zipCode: string;
+}
+
+type Properties = CanadianAddress | AmericanAddress;
+
+export class AddressComp extends React.Component<Properties, void> {
+  public render() {
+    return null;
+  }
+}
+
+let a = <AddressComp postalCode='T1B 0L3' street="vancouver" country="CA" />
\ No newline at end of file