Will thief reset a Pokemon's Unburden boost in gen 6?

Question

I'm wandering if GF changed how unburden works in gen 6, will you still keep the unburden boost if you obtain an opponent's held item? If it does, then thief can be a very good option on belly-burden Slurpuff.

Answer 1

Yes it will reset the boost.

Its description from PS!:
>Speed is doubled on held item loss; boost is lost if it switches, gets new item/Ability.

and Bulbapedia:
>Unburden doubles the Pokémon's Speed stat when the Pokémon's held item is lost. If there is no held item to begin with or if a held item is traded for another, Unburden will not be activated.
This is the

Source

Hope I helped.