Hellickson and Walker will forego free agency this offseason and stay with their former clubs through at least the 2017 season.
All eight other players--including Yoenis Cespedes, Justin Turner, Kenley Jansen, Edwin Encarnacion, Jose Bautista, Mark Trumbo, Ian Desmond, and Dexter Fowler--have declined their respective offers and will become free agents.
These players are free to sign with any team, however, their next club must forfeit their first unprotected draft pick in the 2017 MLB Draft. Their 2016 club, in return for losing the free agent, gains a compensation pick between the 1st- and 2nd-rounds. This is only the case, however, if the player signs somewhere other than their 2016 club.
Hellickson, 29, would have been one of the better free agents in a weak starting pitching class, but decided to accept the QO due to the draft pick concerns. He posted a very solid 12-10 record with a 3.71 ERA and a 154-45 strikeout-to-walk ratio in 189 innings with the Phillies last year. He was worth 3.2 fWAR.
As for Walker, he had season ending back surgery. With this in mind, it's possible that he decided to take the QO to rebuild his value going into next offseason. Despite this, however, he did have a good 2016 campaign, though slightly shortened. In 458 plate appearances, Walker hit for a .282/.347/.476 slash with 23 home runs and 55 RBI. He was worth 3.7 fWAR.
Hellickson and Walker become the fourth and fifth players, respectively, to take the qualifying offer in its short history. The first three (Colby Rasmus, Brett Anderson, Matt Wieters) all took their deals last year.
The qualifying offer systam as a whole has been looked at as an impediment to new free agents and could be scrapped with the Collective Bargaining Agreement set to expire this December.