I know not many will care, but this sucks, as he is a really cool dude.
Taken from Periphery's Facebook:
"We have some sad news to announce, unfortunately Tom Murphy has decided to leave the band:
"I'm sorry to announce that as of today I will no longer be playing bass for Periphery. I have had so many unforgettable experiences and have met so many wonderful people while playing with the band and just want to say thank you to all the fans for making that possible. I am leaving to pursue something new. If you are interested following up with me, feel free to add my personal page at facebook.com/tom.h.murphy.
We're very saddened by this but wish him the best of luck in his future endeavors. Fortunately this will not effect our upcoming touring plans as Nolly from will be filling in on bass and Mark Holcomb will take up his position as full-time guitarist."