Eloquent: belongsToMany with union

Hi,

consider the following simplified datamodel:

A product can contain many options. An option belongs to many products.

3 tables: Products, Options and Product_Options

However, there is an attribute "linked_with_all_products" (true/false) on the Options table, when checked, the option is linked with all products and no records are inserted in Product_Options.

Simple question: what is the correct way to retrieve all the options linked with a certain product?

(I'm new to eloquent and laravel)

Thanks in advance,

Koen