It is reported that the man named 'Alligator' is a Lyft driver, who found the phone in the back seat of his car after he dropped off a few passengers.
He had initially thought that the phone was his own Pixel 2 XL which had somehow fallen at the back of the car. He soon realized it was the 3 XL after seeing the notch and Google logo on the back.
It is said that the man, after shooting a few photos and sending them to Android Police, returned the phone to the original owner.
The Google Pixel 3 XL phone is expected to be unveiled along with the no-notch Pixel 3 on October 9th at an event in New York City.
Earlier, an unboxing video claimed that phone could come with 6.7-inch screen and 3430mAh battery. A leak from XDA Developers via a forum user named "dr.guru" last month revealed Google could release the smartphone in a "Clearly White" colour variant.
The device's rear does not have Pixel line's signature two-tone effect, with what appears to be a reflective glass covering the whole back panel, the report added.