The Canadiens placed Addison on unconditional waivers Friday, Elliotte Friedman of Sportsnet reports.
Addison (shoulder) was reassigned to AHL Laval on Monday, Arpon Basu of The Athletic Montreal reports.
Addison is expected to require six months of recovery time after undergoing shoulder surgery Friday.
Addison will require shoulder surgery next week and he'll be out indefinitely, the Montreal Gazette reports.
Addison agreed to terms on a three-year, entry-level deal Friday.