Q:

Pass object by reference to nested lit-element

There are few nested elements and a main state object.  I see that there is no way pass an object by reference like at Angular for example to be available at the bottom.  I see that it is possible to work through the global environment.  But it is not a clean solution. 

A:

if you want to pass the actual object as a property then you need to use the "dot notation" of lit-html. 
<my-el .data=${dataObject}></my-el>

this is basically the same as doing
document.querySelector('my-el').data = dataObject;

