A minimum of two forwards and one defenceman must be exposed who have played 40 games the previous season, or a total of 70 over the previous two.
There is also a requirement that the 40/70 players are under contract for the first expansion season.
This will be an interesting bit. I wonder if that compels Shero give Josefson a 2+ year deal if only to have somebody to expose.
Although the other option is making moves right before the expansion draft (presumably June 2017). Like giving up a C- prospect you weren't going to re-sign for some other team's 4th liner.