I don't know if this is an issue with React or IE11 but when an the input initially contains an EN-dash (8211) it fires the change event. 
JSFiddle http://jsfiddle.net/uH539/10/

name="fruit"
                defaultChecked={true}
                onChange={emptyFunction}
              />
            </form>
          </div>
        );
      },
    });
    var stub = ReactTestUtils.renderIntoDocument(<RadioGroup />);
    var aNode = ReactDOM.findDOMNode(stub.refs.a);
    var bNode = ReactDOM.findDOMNode(stub.refs.b);
    var cNode = ReactDOM.findDOMNode(stub.refs.c);
    expect(aNode.checked).toBe(true);
    expect(bNode.checked).toBe(false);
    
    expect(cNode.checked).toBe(true);
    bNode.checked = true;
    
    
    
    aNode.checked = false;
    expect(cNode.checked).toBe(true);
    
    ReactTestUtils.Simulate.change(bNode);
    
    expect(aNode.checked).toBe(true);
    expect(cNode.checked).toBe(true);
  });
  it('should support ReactLink', function() {