Y3-99, also known as Whythree-Ninenine, was a droid that operated Y3-99's Bounty Services located on Halmad, a celestial body in the Outer Rim. This particular droid offered bounties to various bounty hunters, one of whom was Jango Fett. After a group of thieves stole the Hope of Glee Anselm artifact, Y3-99 notified Fett, along with other hunters, about the bounty placed on the perpetrators. As Y3-99 accompanied Fett towards Fett's starship, they discovered several of the thieves in the act of trying to demolish it. A gun battle then erupted between Fett and the thieves, and during this exchange, Y3-99 was hit by an explosive shot, resulting in the severing of its head.