Nobody knows for sure what the new CBA is going to outline in terms of when players reach either restricted or unrestricted free agency, but the Minnesota Vikings aren't taking any chances, offering tender offers to players that could potentially be restricted free agents this off-season.
The biggest names on that list are wide receiver Sidney Rice and defensive end Ray Edwards, who were both tendered at the first-round level. That means that, if it turns out that Rice or Edwards is an restricted free agent this summer as opposed to an unrestricted one, any team that signs them away from the Vikings would have to give up a first-round pick to the Vikings if the team chose not to match an offer sheet.
The team tendered three players at the second-round level as well. Those players are offensive lineman Ryan Cook, safety Husain Abdullah, and defensive end Brian Robison. Two players, linebacker Erin Henderson and safety Eric Frampton, were given what are called "right of first refusal" tenders, which basically means that if another team attempts to sign them to an offer sheet, the Vikings can match it if they wish, but will get no compensation if they choose not to match.
Players that were non-tendered by the Vikings include quarterback Tarvaris Jackson, wide receiver Hank Baskett, defensive tackle Fred Evans, and fullback Naufahu Tahi.
If the new CBA treats unrestricted free agency the same as the last CBA did, then Edwards, Cook, Rice, Robison, and Frampton would be unrestricted free agents, as they all have at least four years of service (Edwards and Cook have five). Henderson and Abdullah only have three years in the league, and would likely still be restricted free agents under any scenario.