I believe so (Destiny)

by DaDerga, Baile Átha Cliath, Monday, May 05, 2014, 16:51 (3857 days ago) @ Phoenix_9286

"There's a vault where you can trade items between your characters," says Green. "So you can say, 'great, when I roll a warlock I'm absolutely going to use this' and into the vault it goes. Weapons are all available to all classes, but, say, a warlock helmet is class-specific so you pick it up and put it in the vault. We have people in the studio who would play as two characters, get items for their other character and use that to get ahead of other people in a PvP competition."

– http://www.theguardian.com/technology/2014/apr/28/destiny-hands-on-bungie-xbox-playstationshared-world-shooter

You can indeed trade between builds it seems.