From James Mirtle at the Globe and Mail:
Byfuglien, Sopel and Eager were set to make roughly $6.33-million this season once Eager, a restricted free agent, was signed to a new contract. Chicago took back only Reasoner’s NHL salary in the deal ($1.15-million), meaning the Blackhawks have freed up close to $5-million.
Chicago, however, only has 13 players signed for next season and will likely need to move more salary to sign other RFAs like netminder Antti Niemi and fill out the rest of its roster.