Pardon me? This is perhaps the most basic fact about corporations. Every corporation's ownership is defined by common shares, regardless of their status as public or private.
I ask again - how do YOU think ownership of private companies is defined if not for common shares?
I own portions of several private companies, and in each case I own common shares. Again, this is the case in EVERY corporation, both public and private.
In the case of AmeriResource, the old common shares, which were traded publicly, were cancelled. New, non-publicly traded common shares were issued to the secured debtor and now he owns 100% of the Company.