Luggage lost, laptop lost, phone lost in taxis are generally hard to recover.
Here is some information that can be helpful.
Stuff lost in the taxis from SFO to any city:
Call Lost and Found: 650-821-7014,
Email: SFOLostandFound@flysfo.com
Stuff lost in the taxis from SJC to any city:
Lost and Found
(Mon - Fri: 7am - 6pm, 2nd Floor above main lobby) Contact the Lost and Found: (408) 277-5419.
For items lost during flight:
contact the specific airline.
Stuff lost in one of our cab:
Click chat box, leave a message on chat,
provide us your reservation number, we will track it down.