From Gizmodo:
The person who eventually ended up with the lost iPhone was sitting next to Powell. He was drinking with a friend too. He noticed Powell on the stool next to him but didn’t think twice about him at the time. Not until Powell had already left the bar, and a random really drunk guy—who’d been sitting on the other side of Powell—returned from the bathroom to his own stool.
The Random Really Drunk Guy pointed at the iPhone sitting on the stool, the precious prototype left by the young Apple engineer.
“Hey man, is that your iPhone?” asked Random Really Drunk Guy.
“Hmmm, what?” replied the person who ended up with the iPhone. “No, no, it isn’t mine.”
“Ooooh, I guess it’s your friend’s then,” referring to a friend who at the time was in the bathroom. “Here, take it,” said the Random Really Drunk Guy, handing it to him. “You don’t want to lose it.” After that, the Random Really Drunk Guy also left the bar.
I have a pretty strong suspicion that this “Really Random Drunk Guy” is a fabrication of the guy who found the iPhone — “I didn’t pick it up; it was handed to me.”