Grossman is scheduled to become an unrestricted free agent July 1.
"Well, obviously when guys have contracts and they're nearing their end, you make decisions on going forward," Stars GM Joe Nieuwendyk said. "I think as an organization we felt that we have some depth at that position now which we hadn't had in previous years and made the decision to make the deal that we did in order to give not only Mark Fistric more of an opportunity, but to get Adam Pardy going, and we have some kids that are knocking on the door, as well."
The Flyers sent a 2012 second-round pick and a 2013 third-round pick to Dallas in exchange for the 27-year-old Grossman.
"He is experienced, he is a bigger body and he is a good solid defensive defenseman," Flyers GM Paul Holmgren told Philadelphia media. "He can kill penalties for us and play regular shifts. He can chew up minutes. Like I said, he is a big body."
Nieuwendyk said there was a lot of interest in Grossman, a solid defensive defenseman.
"I've had discussions with a number of teams over the past couple of months. Nick being the player that he is was a sought-after guy for a lot of teams," Nieuwendyk said. "I think it just kind of came together with Philadelphia today over a few days. We wish him luck. It's a good fit for him."
Grossman, at 6-foot-4 and 230 pounds, played in 52 games for the Stars this season, with five assists and 26 penalty minutes. He's played 333 NHL games, registering three goals and 38 assists for 41 points.
Mark Stepneski covers the Stars for ESPNDallas.com.